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authorÁlvaro Fernández Rojas <noltari@gmail.com>2016-04-24 13:03:39 +0200
committerÁlvaro Fernández Rojas <noltari@gmail.com>2016-04-24 13:03:39 +0200
commit525b311bf869d7e252d744e501e227263a955c8e (patch)
tree4c644f534e5b577b9256d26b1e9a2e4a0453698e /target/linux/brcm2708/patches-4.4/0143-bcm2835-sdhost-Major-revision.patch
parent0ab31bfced9666f3fb58acdb5833a93e4f4f5f7e (diff)
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brcm2708: update linux 4.4 patches to latest version
As usual these patches were extracted from the raspberry pi repo: https://github.com/raspberrypi/linux/tree/rpi-4.4.y Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0143-bcm2835-sdhost-Major-revision.patch')
-rw-r--r--target/linux/brcm2708/patches-4.4/0143-bcm2835-sdhost-Major-revision.patch2070
1 files changed, 2070 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0143-bcm2835-sdhost-Major-revision.patch b/target/linux/brcm2708/patches-4.4/0143-bcm2835-sdhost-Major-revision.patch
new file mode 100644
index 0000000..fb31894
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.4/0143-bcm2835-sdhost-Major-revision.patch
@@ -0,0 +1,2070 @@
+From 978d4ec47c4a66491140e964939889c427feee64 Mon Sep 17 00:00:00 2001
+From: Phil Elwell <phil@raspberrypi.org>
+Date: Thu, 11 Feb 2016 16:51:01 +0000
+Subject: [PATCH 143/304] bcm2835-sdhost: Major revision
+
+This is a significant revision of the bcm2835-sdhost driver. It
+improves on the original in a number of ways:
+
+1) Through the use of CMD23 for reads it appears to avoid problems
+ reading some sectors on certain high speed cards.
+2) Better atomicity to prevent crashes.
+3) Higher performance.
+4) Activity logging included, for easier diagnosis in the event
+ of a problem.
+
+Signed-off-by: Phil Elwell <phil@raspberrypi.org>
+---
+ drivers/mmc/host/bcm2835-sdhost.c | 1284 ++++++++++++++++++++-----------------
+ 1 file changed, 686 insertions(+), 598 deletions(-)
+
+--- a/drivers/mmc/host/bcm2835-sdhost.c
++++ b/drivers/mmc/host/bcm2835-sdhost.c
+@@ -2,7 +2,7 @@
+ * BCM2835 SD host driver.
+ *
+ * Author: Phil Elwell <phil@raspberrypi.org>
+- * Copyright 2015
++ * Copyright (C) 2015-2016 Raspberry Pi (Trading) Ltd.
+ *
+ * Based on
+ * mmc-bcm2835.c by Gellert Weisz
+@@ -24,12 +24,13 @@
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+-#define SAFE_READ_THRESHOLD 4
+-#define SAFE_WRITE_THRESHOLD 4
+-#define ALLOW_DMA 1
+-#define ALLOW_CMD23 0
+-#define ALLOW_FAST 1
+-#define USE_BLOCK_IRQ 1
++#define FIFO_READ_THRESHOLD 4
++#define FIFO_WRITE_THRESHOLD 4
++#define ALLOW_CMD23_READ 1
++#define ALLOW_CMD23_WRITE 0
++#define ENABLE_LOG 1
++#define SDDATA_FIFO_PIO_BURST 8
++#define CMD_DALLY_US 1
+
+ #include <linux/delay.h>
+ #include <linux/module.h>
+@@ -48,6 +49,7 @@
+ #include <linux/dma-mapping.h>
+ #include <linux/of_dma.h>
+ #include <linux/time.h>
++#include <linux/workqueue.h>
+
+ #define DRIVER_NAME "sdhost-bcm2835"
+
+@@ -110,6 +112,28 @@
+ #define SDEDM_READ_THRESHOLD_SHIFT 14
+ #define SDEDM_THRESHOLD_MASK 0x1f
+
++#define SDEDM_FSM_MASK 0xf
++#define SDEDM_FSM_IDENTMODE 0x0
++#define SDEDM_FSM_DATAMODE 0x1
++#define SDEDM_FSM_READDATA 0x2
++#define SDEDM_FSM_WRITEDATA 0x3
++#define SDEDM_FSM_READWAIT 0x4
++#define SDEDM_FSM_READCRC 0x5
++#define SDEDM_FSM_WRITECRC 0x6
++#define SDEDM_FSM_WRITEWAIT1 0x7
++#define SDEDM_FSM_POWERDOWN 0x8
++#define SDEDM_FSM_POWERUP 0x9
++#define SDEDM_FSM_WRITESTART1 0xa
++#define SDEDM_FSM_WRITESTART2 0xb
++#define SDEDM_FSM_GENPULSES 0xc
++#define SDEDM_FSM_WRITEWAIT2 0xd
++#define SDEDM_FSM_STARTPOWDOWN 0xf
++
++#define SDDATA_FIFO_WORDS 16
++
++#define USE_CMD23_FLAGS ((ALLOW_CMD23_READ * MMC_DATA_READ) | \
++ (ALLOW_CMD23_WRITE * MMC_DATA_WRITE))
++
+ #define MHZ 1000000
+
+
+@@ -131,15 +155,17 @@ struct bcm2835_host {
+
+ struct tasklet_struct finish_tasklet; /* Tasklet structures */
+
+- struct timer_list timer; /* Timer for timeouts */
++ struct work_struct cmd_wait_wq; /* Workqueue function */
+
+- struct timer_list pio_timer; /* PIO error detection timer */
++ struct timer_list timer; /* Timer for timeouts */
+
+ struct sg_mapping_iter sg_miter; /* SG state for PIO */
+ unsigned int blocks; /* remaining PIO blocks */
+
+ int irq; /* Device IRQ */
+
++ u32 cmd_quick_poll_retries;
++ u32 ns_per_fifo_word;
+
+ /* cached registers */
+ u32 hcfg;
+@@ -154,16 +180,21 @@ struct bcm2835_host {
+
+ unsigned int use_busy:1; /* Wait for busy interrupt */
+
+- unsigned int debug:1; /* Enable debug output */
++ unsigned int use_sbc:1; /* Send CMD23 */
+
+- u32 thread_isr;
++ unsigned int debug:1; /* Enable debug output */
+
+ /*DMA part*/
+ struct dma_chan *dma_chan_rx; /* DMA channel for reads */
+ struct dma_chan *dma_chan_tx; /* DMA channel for writes */
++ struct dma_chan *dma_chan; /* Channel in used */
++ struct dma_async_tx_descriptor *dma_desc;
++ u32 dma_dir;
++ u32 drain_words;
++ struct page *drain_page;
++ u32 drain_offset;
+
+ bool allow_dma;
+- bool have_dma;
+ bool use_dma;
+ /*end of DMA part*/
+
+@@ -173,13 +204,98 @@ struct bcm2835_host {
+ u32 overclock_50; /* frequency to use when 50MHz is requested (in MHz) */
+ u32 overclock; /* Current frequency if overclocked, else zero */
+ u32 pio_limit; /* Maximum block count for PIO (0 = always DMA) */
++};
+
+- u32 debug_flags;
++#if ENABLE_LOG
+
+- u32 sectors; /* Cached card size in sectors */
+- u32 single_read_sectors[8];
++struct log_entry_struct {
++ char event[4];
++ u32 timestamp;
++ u32 param1;
++ u32 param2;
+ };
+
++typedef struct log_entry_struct LOG_ENTRY_T;
++
++LOG_ENTRY_T *sdhost_log_buf;
++dma_addr_t sdhost_log_addr;
++static u32 sdhost_log_idx;
++static spinlock_t log_lock;
++static void __iomem *timer_base;
++
++#define LOG_ENTRIES (256*1)
++#define LOG_SIZE (sizeof(LOG_ENTRY_T)*LOG_ENTRIES)
++
++static void log_init(u32 bus_to_phys)
++{
++ spin_lock_init(&log_lock);
++ sdhost_log_buf = dma_zalloc_coherent(NULL, LOG_SIZE, &sdhost_log_addr,
++ GFP_KERNEL);
++ if (sdhost_log_buf) {
++ pr_err("sdhost: log_buf @ %p (%x)\n",
++ sdhost_log_buf, sdhost_log_addr);
++ timer_base = ioremap_nocache(bus_to_phys + 0x7e003000, SZ_4K);
++ if (!timer_base)
++ pr_err("sdhost: failed to remap timer\n");
++ }
++ else
++ pr_err("sdhost: failed to allocate log buf\n");
++}
++
++static void log_event_impl(const char *event, u32 param1, u32 param2)
++{
++ if (sdhost_log_buf) {
++ LOG_ENTRY_T *entry;
++ unsigned long flags;
++
++ spin_lock_irqsave(&log_lock, flags);
++
++ entry = sdhost_log_buf + sdhost_log_idx;
++ memcpy(entry->event, event, 4);
++ entry->timestamp = (readl(timer_base + 4) & 0x3fffffff) +
++ (smp_processor_id()<<30);
++ entry->param1 = param1;
++ entry->param2 = param2;
++ sdhost_log_idx = (sdhost_log_idx + 1) % LOG_ENTRIES;
++
++ spin_unlock_irqrestore(&log_lock, flags);
++ }
++}
++
++static void log_dump(void)
++{
++ if (sdhost_log_buf) {
++ LOG_ENTRY_T *entry;
++ unsigned long flags;
++ int idx;
++
++ spin_lock_irqsave(&log_lock, flags);
++
++ idx = sdhost_log_idx;
++ do {
++ entry = sdhost_log_buf + idx;
++ if (entry->event[0] != '\0')
++ pr_err("[%08x] %.4s %x %x\n",
++ entry->timestamp,
++ entry->event,
++ entry->param1,
++ entry->param2);
++ idx = (idx + 1) % LOG_ENTRIES;
++ } while (idx != sdhost_log_idx);
++
++ spin_unlock_irqrestore(&log_lock, flags);
++ }
++}
++
++#define log_event(event, param1, param2) log_event_impl(event, param1, param2)
++
++#else
++
++#define log_init(x) (void)0
++#define log_event(event, param1, param2) (void)0
++#define log_dump() (void)0
++
++#endif
+
+ static inline void bcm2835_sdhost_write(struct bcm2835_host *host, u32 val, int reg)
+ {
+@@ -201,7 +317,7 @@ static void bcm2835_sdhost_dumpcmd(struc
+ const char *label)
+ {
+ if (cmd)
+- pr_info("%s:%c%s op %d arg 0x%x flags 0x%x - resp %08x %08x %08x %08x, err %d\n",
++ pr_err("%s:%c%s op %d arg 0x%x flags 0x%x - resp %08x %08x %08x %08x, err %d\n",
+ mmc_hostname(host->mmc),
+ (cmd == host->cmd) ? '>' : ' ',
+ label, cmd->opcode, cmd->arg, cmd->flags,
+@@ -211,73 +327,74 @@ static void bcm2835_sdhost_dumpcmd(struc
+
+ static void bcm2835_sdhost_dumpregs(struct bcm2835_host *host)
+ {
+- bcm2835_sdhost_dumpcmd(host, host->mrq->sbc, "sbc");
+- bcm2835_sdhost_dumpcmd(host, host->mrq->cmd, "cmd");
+- if (host->mrq->data)
+- pr_err("%s: data blocks %x blksz %x - err %d\n",
+- mmc_hostname(host->mmc),
+- host->mrq->data->blocks,
+- host->mrq->data->blksz,
+- host->mrq->data->error);
+- bcm2835_sdhost_dumpcmd(host, host->mrq->stop, "stop");
++ if (host->mrq)
++ {
++ bcm2835_sdhost_dumpcmd(host, host->mrq->sbc, "sbc");
++ bcm2835_sdhost_dumpcmd(host, host->mrq->cmd, "cmd");
++ if (host->mrq->data)
++ pr_err("%s: data blocks %x blksz %x - err %d\n",
++ mmc_hostname(host->mmc),
++ host->mrq->data->blocks,
++ host->mrq->data->blksz,
++ host->mrq->data->error);
++ bcm2835_sdhost_dumpcmd(host, host->mrq->stop, "stop");
++ }
+
+- pr_info("%s: =========== REGISTER DUMP ===========\n",
++ pr_err("%s: =========== REGISTER DUMP ===========\n",
+ mmc_hostname(host->mmc));
+
+- pr_info("%s: SDCMD 0x%08x\n",
++ pr_err("%s: SDCMD 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDCMD));
+- pr_info("%s: SDARG 0x%08x\n",
++ pr_err("%s: SDARG 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDARG));
+- pr_info("%s: SDTOUT 0x%08x\n",
++ pr_err("%s: SDTOUT 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDTOUT));
+- pr_info("%s: SDCDIV 0x%08x\n",
++ pr_err("%s: SDCDIV 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDCDIV));
+- pr_info("%s: SDRSP0 0x%08x\n",
++ pr_err("%s: SDRSP0 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDRSP0));
+- pr_info("%s: SDRSP1 0x%08x\n",
++ pr_err("%s: SDRSP1 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDRSP1));
+- pr_info("%s: SDRSP2 0x%08x\n",
++ pr_err("%s: SDRSP2 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDRSP2));
+- pr_info("%s: SDRSP3 0x%08x\n",
++ pr_err("%s: SDRSP3 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDRSP3));
+- pr_info("%s: SDHSTS 0x%08x\n",
++ pr_err("%s: SDHSTS 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDHSTS));
+- pr_info("%s: SDVDD 0x%08x\n",
++ pr_err("%s: SDVDD 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDVDD));
+- pr_info("%s: SDEDM 0x%08x\n",
++ pr_err("%s: SDEDM 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDEDM));
+- pr_info("%s: SDHCFG 0x%08x\n",
++ pr_err("%s: SDHCFG 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDHCFG));
+- pr_info("%s: SDHBCT 0x%08x\n",
++ pr_err("%s: SDHBCT 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDHBCT));
+- pr_info("%s: SDHBLC 0x%08x\n",
++ pr_err("%s: SDHBLC 0x%08x\n",
+ mmc_hostname(host->mmc),
+ bcm2835_sdhost_read(host, SDHBLC));
+
+- pr_info("%s: ===========================================\n",
++ pr_err("%s: ===========================================\n",
+ mmc_hostname(host->mmc));
+ }
+
+-
+ static void bcm2835_sdhost_set_power(struct bcm2835_host *host, bool on)
+ {
+ bcm2835_sdhost_write(host, on ? 1 : 0, SDVDD);
+ }
+
+-
+ static void bcm2835_sdhost_reset_internal(struct bcm2835_host *host)
+ {
+ u32 temp;
+@@ -300,26 +417,24 @@ static void bcm2835_sdhost_reset_interna
+ temp = bcm2835_sdhost_read(host, SDEDM);
+ temp &= ~((SDEDM_THRESHOLD_MASK<<SDEDM_READ_THRESHOLD_SHIFT) |
+ (SDEDM_THRESHOLD_MASK<<SDEDM_WRITE_THRESHOLD_SHIFT));
+- temp |= (SAFE_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) |
+- (SAFE_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT);
++ temp |= (FIFO_READ_THRESHOLD << SDEDM_READ_THRESHOLD_SHIFT) |
++ (FIFO_WRITE_THRESHOLD << SDEDM_WRITE_THRESHOLD_SHIFT);
+ bcm2835_sdhost_write(host, temp, SDEDM);
+ mdelay(10);
+ bcm2835_sdhost_set_power(host, true);
+ mdelay(10);
+ host->clock = 0;
+- host->sectors = 0;
+- host->single_read_sectors[0] = ~0;
+ bcm2835_sdhost_write(host, host->hcfg, SDHCFG);
+ bcm2835_sdhost_write(host, host->cdiv, SDCDIV);
+ mmiowb();
+ }
+
+-
+ static void bcm2835_sdhost_reset(struct mmc_host *mmc)
+ {
+ struct bcm2835_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ spin_lock_irqsave(&host->lock, flags);
++ log_event("RST<", 0, 0);
+
+ bcm2835_sdhost_reset_internal(host);
+
+@@ -344,82 +459,48 @@ static void bcm2835_sdhost_init(struct b
+ }
+ }
+
+-static bool bcm2835_sdhost_is_write_complete(struct bcm2835_host *host)
++static void bcm2835_sdhost_wait_transfer_complete(struct bcm2835_host *host)
+ {
+- bool write_complete = ((bcm2835_sdhost_read(host, SDEDM) & 0xf) == 1);
++ int timediff;
++ u32 alternate_idle;
++ u32 edm;
+
+- if (!write_complete) {
+- /* Request an IRQ for the last block */
+- host->hcfg |= SDHCFG_BLOCK_IRPT_EN;
+- bcm2835_sdhost_write(host, host->hcfg, SDHCFG);
+- if ((bcm2835_sdhost_read(host, SDEDM) & 0xf) == 1) {
+- /* The write has now completed. Disable the interrupt
+- and clear the status flag */
+- host->hcfg &= ~SDHCFG_BLOCK_IRPT_EN;
+- bcm2835_sdhost_write(host, host->hcfg, SDHCFG);
+- bcm2835_sdhost_write(host, SDHSTS_BLOCK_IRPT, SDHSTS);
+- write_complete = true;
+- }
+- }
++ alternate_idle = (host->mrq->data->flags & MMC_DATA_READ) ?
++ SDEDM_FSM_READWAIT : SDEDM_FSM_WRITESTART1;
+
+- return write_complete;
+-}
++ edm = bcm2835_sdhost_read(host, SDEDM);
+
+-static void bcm2835_sdhost_wait_write_complete(struct bcm2835_host *host)
+-{
+- int timediff;
+-#ifdef DEBUG
+- static struct timeval start_time;
+- static int max_stall_time = 0;
+- static int total_stall_time = 0;
+- struct timeval before, after;
+-
+- do_gettimeofday(&before);
+- if (max_stall_time == 0)
+- start_time = before;
+-#endif
++ log_event("WTC<", edm, 0);
+
+ timediff = 0;
+
+ while (1) {
+- u32 edm = bcm2835_sdhost_read(host, SDEDM);
+- if ((edm & 0xf) == 1)
++ u32 fsm = edm & SDEDM_FSM_MASK;
++ if ((fsm == SDEDM_FSM_IDENTMODE) ||
++ (fsm == SDEDM_FSM_DATAMODE))
+ break;
+- timediff++;
+- if (timediff > 5000000) {
+-#ifdef DEBUG
+- do_gettimeofday(&after);
+- timediff = (after.tv_sec - before.tv_sec)*1000000 +
+- (after.tv_usec - before.tv_usec);
++ if (fsm == alternate_idle) {
++ bcm2835_sdhost_write(host,
++ edm | SDEDM_FORCE_DATA_MODE,
++ SDEDM);
++ break;
++ }
+
+- pr_err(" wait_write_complete - still waiting after %dus\n",
+- timediff);
+-#else
+- pr_err(" wait_write_complete - still waiting after %d retries\n",
++ timediff++;
++ if (timediff == 100000) {
++ pr_err("%s: wait_transfer_complete - still waiting after %d retries\n",
++ mmc_hostname(host->mmc),
+ timediff);
+-#endif
++ log_dump();
+ bcm2835_sdhost_dumpregs(host);
+- host->data->error = -ETIMEDOUT;
++ host->mrq->data->error = -ETIMEDOUT;
++ log_event("WTC!", edm, 0);
+ return;
+ }
++ cpu_relax();
++ edm = bcm2835_sdhost_read(host, SDEDM);
+ }
+-
+-#ifdef DEBUG
+- do_gettimeofday(&after);
+- timediff = (after.tv_sec - before.tv_sec)*1000000 + (after.tv_usec - before.tv_usec);
+-
+- total_stall_time += timediff;
+- if (timediff > max_stall_time)
+- max_stall_time = timediff;
+-
+- if ((after.tv_sec - start_time.tv_sec) > 10) {
+- pr_debug(" wait_write_complete - max wait %dus, total %dus\n",
+- max_stall_time, total_stall_time);
+- start_time = after;
+- max_stall_time = 0;
+- total_stall_time = 0;
+- }
+-#endif
++ log_event("WTC>", edm, 0);
+ }
+
+ static void bcm2835_sdhost_finish_data(struct bcm2835_host *host);
+@@ -427,65 +508,44 @@ static void bcm2835_sdhost_finish_data(s
+ static void bcm2835_sdhost_dma_complete(void *param)
+ {
+ struct bcm2835_host *host = param;
+- struct dma_chan *dma_chan;
++ struct mmc_data *data = host->data;
+ unsigned long flags;
+- u32 dir_data;
+
+ spin_lock_irqsave(&host->lock, flags);
++ log_event("DMA<", (u32)host->data, bcm2835_sdhost_read(host, SDHSTS));
++ log_event("DMA ", bcm2835_sdhost_read(host, SDCMD),
++ bcm2835_sdhost_read(host, SDEDM));
+
+- if (host->data) {
+- bool write_complete;
+- if (USE_BLOCK_IRQ)
+- write_complete = bcm2835_sdhost_is_write_complete(host);
+- else {
+- bcm2835_sdhost_wait_write_complete(host);
+- write_complete = true;
+- }
+- pr_debug("dma_complete() - write_complete=%d\n",
+- write_complete);
+-
+- if (write_complete || (host->data->flags & MMC_DATA_READ))
+- {
+- if (write_complete) {
+- dma_chan = host->dma_chan_tx;
+- dir_data = DMA_TO_DEVICE;
+- } else {
+- dma_chan = host->dma_chan_rx;
+- dir_data = DMA_FROM_DEVICE;
+- }
+-
+- dma_unmap_sg(dma_chan->device->dev,
+- host->data->sg, host->data->sg_len,
+- dir_data);
++ if (host->dma_chan) {
++ dma_unmap_sg(host->dma_chan->device->dev,
++ data->sg, data->sg_len,
++ host->dma_dir);
+
+- bcm2835_sdhost_finish_data(host);
+- }
++ host->dma_chan = NULL;
+ }
+
+- spin_unlock_irqrestore(&host->lock, flags);
+-}
++ if (host->drain_words) {
++ void *page;
++ u32 *buf;
+
+-static bool data_transfer_wait(struct bcm2835_host *host)
+-{
+- unsigned long timeout = 1000000;
+- while (timeout)
+- {
+- u32 sdhsts = bcm2835_sdhost_read(host, SDHSTS);
+- if (sdhsts & SDHSTS_DATA_FLAG) {
+- bcm2835_sdhost_write(host, SDHSTS_DATA_FLAG, SDHSTS);
+- break;
++ page = kmap_atomic(host->drain_page);
++ buf = page + host->drain_offset;
++
++ while (host->drain_words) {
++ u32 edm = bcm2835_sdhost_read(host, SDEDM);
++ if ((edm >> 4) & 0x1f)
++ *(buf++) = bcm2835_sdhost_read(host,
++ SDDATA);
++ host->drain_words--;
+ }
+- timeout--;
+- }
+- if (timeout == 0) {
+- pr_err("%s: Data %s timeout\n",
+- mmc_hostname(host->mmc),
+- (host->data->flags & MMC_DATA_READ) ? "read" : "write");
+- bcm2835_sdhost_dumpregs(host);
+- host->data->error = -ETIMEDOUT;
+- return false;
++
++ kunmap_atomic(page);
+ }
+- return true;
++
++ bcm2835_sdhost_finish_data(host);
++
++ log_event("DMA>", (u32)host->data, 0);
++ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+ static void bcm2835_sdhost_read_block_pio(struct bcm2835_host *host)
+@@ -493,32 +553,83 @@ static void bcm2835_sdhost_read_block_pi
+ unsigned long flags;
+ size_t blksize, len;
+ u32 *buf;
++ unsigned long wait_max;
+
+ blksize = host->data->blksz;
+
++ wait_max = jiffies + msecs_to_jiffies(host->pio_timeout);
++
+ local_irq_save(flags);
+
+ while (blksize) {
+- if (!sg_miter_next(&host->sg_miter))
+- BUG();
++ int copy_words;
++ u32 hsts = 0;
++
++ if (!sg_miter_next(&host->sg_miter)) {
++ host->data->error = -EINVAL;
++ break;
++ }
+
+ len = min(host->sg_miter.length, blksize);
+- BUG_ON(len % 4);
++ if (len % 4) {
++ host->data->error = -EINVAL;
++ break;
++ }
+
+ blksize -= len;
+ host->sg_miter.consumed = len;
+
+ buf = (u32 *)host->sg_miter.addr;
+
+- while (len) {
+- if (!data_transfer_wait(host))
+- break;
++ copy_words = len/4;
++
++ while (copy_words) {
++ int burst_words, words;
++ u32 edm;
++
++ burst_words = SDDATA_FIFO_PIO_BURST;
++ if (burst_words > copy_words)
++ burst_words = copy_words;
++ edm = bcm2835_sdhost_read(host, SDEDM);
++ words = ((edm >> 4) & 0x1f);
++
++ if (words < burst_words) {
++ int fsm_state = (edm & SDEDM_FSM_MASK);
++ if ((fsm_state != SDEDM_FSM_READDATA) &&
++ (fsm_state != SDEDM_FSM_READWAIT) &&
++ (fsm_state != SDEDM_FSM_READCRC)) {
++ hsts = bcm2835_sdhost_read(host,
++ SDHSTS);
++ pr_err("%s: fsm %x, hsts %x\n",
++ mmc_hostname(host->mmc),
++ fsm_state, hsts);
++ if (hsts & SDHSTS_ERROR_MASK)
++ break;
++ }
++
++ if (time_after(jiffies, wait_max)) {
++ pr_err("%s: PIO read timeout - EDM %x\n",
++ mmc_hostname(host->mmc),
++ edm);
++ hsts = SDHSTS_REW_TIME_OUT;
++ break;
++ }
++ ndelay((burst_words - words) *
++ host->ns_per_fifo_word);
++ continue;
++ } else if (words > copy_words) {
++ words = copy_words;
++ }
++
++ copy_words -= words;
+
+- *(buf++) = bcm2835_sdhost_read(host, SDDATA);
+- len -= 4;
++ while (words) {
++ *(buf++) = bcm2835_sdhost_read(host, SDDATA);
++ words--;
++ }
+ }
+
+- if (host->data->error)
++ if (hsts & SDHSTS_ERROR_MASK)
+ break;
+ }
+
+@@ -532,32 +643,83 @@ static void bcm2835_sdhost_write_block_p
+ unsigned long flags;
+ size_t blksize, len;
+ u32 *buf;
++ unsigned long wait_max;
+
+ blksize = host->data->blksz;
+
++ wait_max = jiffies + msecs_to_jiffies(host->pio_timeout);
++
+ local_irq_save(flags);
+
+ while (blksize) {
+- if (!sg_miter_next(&host->sg_miter))
+- BUG();
++ int copy_words;
++ u32 hsts = 0;
++
++ if (!sg_miter_next(&host->sg_miter)) {
++ host->data->error = -EINVAL;
++ break;
++ }
+
+ len = min(host->sg_miter.length, blksize);
+- BUG_ON(len % 4);
++ if (len % 4) {
++ host->data->error = -EINVAL;
++ break;
++ }
+
+ blksize -= len;
+ host->sg_miter.consumed = len;
+
+- buf = host->sg_miter.addr;
++ buf = (u32 *)host->sg_miter.addr;
+
+- while (len) {
+- if (!data_transfer_wait(host))
+- break;
++ copy_words = len/4;
++
++ while (copy_words) {
++ int burst_words, words;
++ u32 edm;
++
++ burst_words = SDDATA_FIFO_PIO_BURST;
++ if (burst_words > copy_words)
++ burst_words = copy_words;
++ edm = bcm2835_sdhost_read(host, SDEDM);
++ words = SDDATA_FIFO_WORDS - ((edm >> 4) & 0x1f);
++
++ if (words < burst_words) {
++ int fsm_state = (edm & SDEDM_FSM_MASK);
++ if ((fsm_state != SDEDM_FSM_WRITEDATA) &&
++ (fsm_state != SDEDM_FSM_WRITESTART1) &&
++ (fsm_state != SDEDM_FSM_WRITESTART2)) {
++ hsts = bcm2835_sdhost_read(host,
++ SDHSTS);
++ pr_err("%s: fsm %x, hsts %x\n",
++ mmc_hostname(host->mmc),
++ fsm_state, hsts);
++ if (hsts & SDHSTS_ERROR_MASK)
++ break;
++ }
+
+- bcm2835_sdhost_write(host, *(buf++), SDDATA);
+- len -= 4;
++ if (time_after(jiffies, wait_max)) {
++ pr_err("%s: PIO write timeout - EDM %x\n",
++ mmc_hostname(host->mmc),
++ edm);
++ hsts = SDHSTS_REW_TIME_OUT;
++ break;
++ }
++ ndelay((burst_words - words) *
++ host->ns_per_fifo_word);
++ continue;
++ } else if (words > copy_words) {
++ words = copy_words;
++ }
++
++ copy_words -= words;
++
++ while (words) {
++ bcm2835_sdhost_write(host, *(buf++), SDDATA);
++ words--;
++ }
+ }
+
+- if (host->data->error)
++ if (hsts & SDHSTS_ERROR_MASK)
+ break;
+ }
+
+@@ -566,12 +728,12 @@ static void bcm2835_sdhost_write_block_p
+ local_irq_restore(flags);
+ }
+
+-
+ static void bcm2835_sdhost_transfer_pio(struct bcm2835_host *host)
+ {
+ u32 sdhsts;
+ bool is_read;
+ BUG_ON(!host->data);
++ log_event("XFP<", (u32)host->data, host->blocks);
+
+ is_read = (host->data->flags & MMC_DATA_READ) != 0;
+ if (is_read)
+@@ -595,28 +757,21 @@ static void bcm2835_sdhost_transfer_pio(
+ is_read ? "read" : "write",
+ sdhsts);
+ host->data->error = -ETIMEDOUT;
+- } else if (!is_read && !host->data->error) {
+- /* Start a timer in case a transfer error occurs because
+- there is no error interrupt */
+- mod_timer(&host->pio_timer, jiffies + host->pio_timeout);
+ }
++ log_event("XFP>", (u32)host->data, host->blocks);
+ }
+
+-
+-static void bcm2835_sdhost_transfer_dma(struct bcm2835_host *host)
++static void bcm2835_sdhost_prepare_dma(struct bcm2835_host *host,
++ struct mmc_data *data)
+ {
+- u32 len, dir_data, dir_slave;
++ int len, dir_data, dir_slave;
+ struct dma_async_tx_descriptor *desc = NULL;
+ struct dma_chan *dma_chan;
+
+- pr_debug("bcm2835_sdhost_transfer_dma()\n");
+-
+- WARN_ON(!host->data);
++ log_event("PRD<", (u32)data, 0);
++ pr_debug("bcm2835_sdhost_prepare_dma()\n");
+
+- if (!host->data)
+- return;
+-
+- if (host->data->flags & MMC_DATA_READ) {
++ if (data->flags & MMC_DATA_READ) {
+ dma_chan = host->dma_chan_rx;
+ dir_data = DMA_FROM_DEVICE;
+ dir_slave = DMA_DEV_TO_MEM;
+@@ -625,35 +780,71 @@ static void bcm2835_sdhost_transfer_dma(
+ dir_data = DMA_TO_DEVICE;
+ dir_slave = DMA_MEM_TO_DEV;
+ }
++ log_event("PRD1", (u32)dma_chan, 0);
+
+ BUG_ON(!dma_chan->device);
+ BUG_ON(!dma_chan->device->dev);
+- BUG_ON(!host->data->sg);
++ BUG_ON(!data->sg);
+
+- len = dma_map_sg(dma_chan->device->dev, host->data->sg,
+- host->data->sg_len, dir_data);
+- if (len > 0) {
+- desc = dmaengine_prep_slave_sg(dma_chan, host->data->sg,
++ /* The block doesn't manage the FIFO DREQs properly for multi-block
++ transfers, so don't attempt to DMA the final few words.
++ Unfortunately this requires the final sg entry to be trimmed.
++ N.B. This code demands that the overspill is contained in
++ a single sg entry.
++ */
++
++ host->drain_words = 0;
++ if ((data->blocks > 1) && (dir_data == DMA_FROM_DEVICE)) {
++ struct scatterlist *sg;
++ u32 len;
++ int i;
++
++ len = min((u32)(FIFO_READ_THRESHOLD - 1) * 4,
++ (u32)data->blocks * data->blksz);
++
++ for_each_sg(data->sg, sg, data->sg_len, i) {
++ if (sg_is_last(sg)) {
++ BUG_ON(sg->length < len);
++ sg->length -= len;
++ host->drain_page = (struct page *)sg->page_link;
++ host->drain_offset = sg->offset + sg->length;
++ }
++ }
++ host->drain_words = len/4;
++ }
++
++ len = dma_map_sg(dma_chan->device->dev, data->sg, data->sg_len,
++ dir_data);
++
++ log_event("PRD2", len, 0);
++ if (len > 0)
++ desc = dmaengine_prep_slave_sg(dma_chan, data->sg,
+ len, dir_slave,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+- } else {
+- dev_err(mmc_dev(host->mmc), "dma_map_sg returned zero length\n");
+- }
++ log_event("PRD3", (u32)desc, 0);
++
+ if (desc) {
+ desc->callback = bcm2835_sdhost_dma_complete;
+ desc->callback_param = host;
+- dmaengine_submit(desc);
+- dma_async_issue_pending(dma_chan);
++ host->dma_desc = desc;
++ host->dma_chan = dma_chan;
++ host->dma_dir = dir_data;
+ }
+-
++ log_event("PDM>", (u32)data, 0);
+ }
+
++static void bcm2835_sdhost_start_dma(struct bcm2835_host *host)
++{
++ log_event("SDMA", (u32)host->data, (u32)host->dma_chan);
++ dmaengine_submit(host->dma_desc);
++ dma_async_issue_pending(host->dma_chan);
++}
+
+ static void bcm2835_sdhost_set_transfer_irqs(struct bcm2835_host *host)
+ {
+ u32 all_irqs = SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN |
+ SDHCFG_BUSY_IRPT_EN;
+- if (host->use_dma)
++ if (host->dma_desc)
+ host->hcfg = (host->hcfg & ~all_irqs) |
+ SDHCFG_BUSY_IRPT_EN;
+ else
+@@ -664,13 +855,13 @@ static void bcm2835_sdhost_set_transfer_
+ bcm2835_sdhost_write(host, host->hcfg, SDHCFG);
+ }
+
+-
+ static void bcm2835_sdhost_prepare_data(struct bcm2835_host *host, struct mmc_command *cmd)
+ {
+ struct mmc_data *data = cmd->data;
+
+ WARN_ON(host->data);
+
++ host->data = data;
+ if (!data)
+ return;
+
+@@ -679,46 +870,19 @@ static void bcm2835_sdhost_prepare_data(
+ BUG_ON(data->blksz > host->mmc->max_blk_size);
+ BUG_ON(data->blocks > 65535);
+
+- host->data = data;
+ host->data_complete = 0;
+ host->flush_fifo = 0;
+ host->data->bytes_xfered = 0;
+
+- if (!host->sectors && host->mmc->card && !(host->debug_flags & 1))
+- {
+- struct mmc_card *card = host->mmc->card;
+- if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
+- /*
+- * The EXT_CSD sector count is in number of 512 byte
+- * sectors.
+- */
+- host->sectors = card->ext_csd.sectors;
+- pr_err("%s: using ext_csd!\n", mmc_hostname(host->mmc));
+- } else {
+- /*
+- * The CSD capacity field is in units of read_blkbits.
+- * set_capacity takes units of 512 bytes.
+- */
+- host->sectors = card->csd.capacity <<
+- (card->csd.read_blkbits - 9);
+- }
+- host->single_read_sectors[0] = host->sectors - 65;
+- host->single_read_sectors[1] = host->sectors - 64;
+- host->single_read_sectors[2] = host->sectors - 33;
+- host->single_read_sectors[3] = host->sectors - 32;
+- host->single_read_sectors[4] = host->sectors - 1;
+- host->single_read_sectors[5] = ~0; /* Safety net */
+- }
+
+- host->use_dma = host->have_dma && (data->blocks > host->pio_limit);
+- if (!host->use_dma) {
++ if (!host->dma_desc) {
++ /* Use PIO */
+ int flags;
+
+- flags = SG_MITER_ATOMIC;
+ if (data->flags & MMC_DATA_READ)
+- flags |= SG_MITER_TO_SG;
++ flags = SG_MITER_TO_SG;
+ else
+- flags |= SG_MITER_FROM_SG;
++ flags = SG_MITER_FROM_SG;
+ sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
+ host->blocks = data->blocks;
+ }
+@@ -726,19 +890,20 @@ static void bcm2835_sdhost_prepare_data(
+ bcm2835_sdhost_set_transfer_irqs(host);
+
+ bcm2835_sdhost_write(host, data->blksz, SDHBCT);
+- bcm2835_sdhost_write(host, host->use_dma ? data->blocks : 0, SDHBLC);
++ bcm2835_sdhost_write(host, data->blocks, SDHBLC);
+
+ BUG_ON(!host->data);
+ }
+
+-
+-void bcm2835_sdhost_send_command(struct bcm2835_host *host, struct mmc_command *cmd)
++bool bcm2835_sdhost_send_command(struct bcm2835_host *host,
++ struct mmc_command *cmd)
+ {
+ u32 sdcmd, sdhsts;
+ unsigned long timeout;
+ int delay;
+
+ WARN_ON(host->cmd);
++ log_event("CMD<", cmd->opcode, cmd->arg);
+
+ if (cmd->data)
+ pr_debug("%s: send_command %d 0x%x "
+@@ -761,9 +926,9 @@ void bcm2835_sdhost_send_command(struct
+ pr_err("%s: previous command never completed.\n",
+ mmc_hostname(host->mmc));
+ bcm2835_sdhost_dumpregs(host);
+- cmd->error = -EIO;
++ cmd->error = -EILSEQ;
+ tasklet_schedule(&host->finish_tasklet);
+- return;
++ return false;
+ }
+ timeout--;
+ udelay(10);
+@@ -791,23 +956,24 @@ void bcm2835_sdhost_send_command(struct
+ if (sdhsts & SDHSTS_ERROR_MASK)
+ bcm2835_sdhost_write(host, sdhsts, SDHSTS);
+
+- bcm2835_sdhost_prepare_data(host, cmd);
+-
+- bcm2835_sdhost_write(host, cmd->arg, SDARG);
+-
+ if ((cmd->flags & MMC_RSP_136) && (cmd->flags & MMC_RSP_BUSY)) {
+ pr_err("%s: unsupported response type!\n",
+ mmc_hostname(host->mmc));
+ cmd->error = -EINVAL;
+ tasklet_schedule(&host->finish_tasklet);
+- return;
++ return false;
+ }
+
++ bcm2835_sdhost_prepare_data(host, cmd);
++
++ bcm2835_sdhost_write(host, cmd->arg, SDARG);
++
+ sdcmd = cmd->opcode & SDCMD_CMD_MASK;
+
+- if (!(cmd->flags & MMC_RSP_PRESENT))
++ host->use_busy = 0;
++ if (!(cmd->flags & MMC_RSP_PRESENT)) {
+ sdcmd |= SDCMD_NO_RESPONSE;
+- else {
++ } else {
+ if (cmd->flags & MMC_RSP_136)
+ sdcmd |= SDCMD_LONG_RESPONSE;
+ if (cmd->flags & MMC_RSP_BUSY) {
+@@ -817,6 +983,7 @@ void bcm2835_sdhost_send_command(struct
+ }
+
+ if (cmd->data) {
++ log_event("CMDD", cmd->data->blocks, cmd->data->blksz);
+ if (host->delay_after_stop) {
+ struct timeval now;
+ int time_since_stop;
+@@ -839,10 +1006,12 @@ void bcm2835_sdhost_send_command(struct
+ }
+
+ bcm2835_sdhost_write(host, sdcmd | SDCMD_NEW_FLAG, SDCMD);
+-}
+
++ return true;
++}
+
+-static void bcm2835_sdhost_finish_command(struct bcm2835_host *host);
++static void bcm2835_sdhost_finish_command(struct bcm2835_host *host,
++ unsigned long *irq_flags);
+ static void bcm2835_sdhost_transfer_complete(struct bcm2835_host *host);
+
+ static void bcm2835_sdhost_finish_data(struct bcm2835_host *host)
+@@ -852,6 +1021,7 @@ static void bcm2835_sdhost_finish_data(s
+ data = host->data;
+ BUG_ON(!data);
+
++ log_event("FDA<", (u32)host->mrq, (u32)host->cmd);
+ pr_debug("finish_data(error %d, stop %d, sbc %d)\n",
+ data->error, data->stop ? 1 : 0,
+ host->mrq->sbc ? 1 : 0);
+@@ -859,10 +1029,7 @@ static void bcm2835_sdhost_finish_data(s
+ host->hcfg &= ~(SDHCFG_DATA_IRPT_EN | SDHCFG_BLOCK_IRPT_EN);
+ bcm2835_sdhost_write(host, host->hcfg, SDHCFG);
+
+- if (data->error) {
+- data->bytes_xfered = 0;
+- } else
+- data->bytes_xfered = data->blksz * data->blocks;
++ data->bytes_xfered = data->error ? 0 : (data->blksz * data->blocks);
+
+ host->data_complete = 1;
+
+@@ -877,9 +1044,9 @@ static void bcm2835_sdhost_finish_data(s
+ }
+ else
+ bcm2835_sdhost_transfer_complete(host);
++ log_event("FDA>", (u32)host->mrq, (u32)host->cmd);
+ }
+
+-
+ static void bcm2835_sdhost_transfer_complete(struct bcm2835_host *host)
+ {
+ struct mmc_data *data;
+@@ -891,6 +1058,7 @@ static void bcm2835_sdhost_transfer_comp
+ data = host->data;
+ host->data = NULL;
+
++ log_event("TCM<", (u32)data, data->error);
+ pr_debug("transfer_complete(error %d, stop %d)\n",
+ data->error, data->stop ? 1 : 0);
+
+@@ -899,88 +1067,114 @@ static void bcm2835_sdhost_transfer_comp
+ * a) open-ended multiblock transfer (no CMD23)
+ * b) error in multiblock transfer
+ */
+- if (data->stop &&
+- (data->error ||
+- !host->mrq->sbc)) {
+- host->flush_fifo = 1;
+- bcm2835_sdhost_send_command(host, data->stop);
+- if (host->delay_after_stop)
+- do_gettimeofday(&host->stop_time);
+- if (!host->use_busy)
+- bcm2835_sdhost_finish_command(host);
++ if (host->mrq->stop && (data->error || !host->use_sbc)) {
++ if (bcm2835_sdhost_send_command(host, host->mrq->stop)) {
++ /* No busy, so poll for completion */
++ if (!host->use_busy)
++ bcm2835_sdhost_finish_command(host, NULL);
++
++ if (host->delay_after_stop)
++ do_gettimeofday(&host->stop_time);
++ }
+ } else {
++ bcm2835_sdhost_wait_transfer_complete(host);
+ tasklet_schedule(&host->finish_tasklet);
+ }
++ log_event("TCM>", (u32)data, 0);
+ }
+
+-static void bcm2835_sdhost_finish_command(struct bcm2835_host *host)
++/* If irq_flags is valid, the caller is in a thread context and is allowed
++ to sleep */
++static void bcm2835_sdhost_finish_command(struct bcm2835_host *host,
++ unsigned long *irq_flags)
+ {
+ u32 sdcmd;
+- unsigned long timeout;
++ u32 retries;
+ #ifdef DEBUG
+ struct timeval before, after;
+ int timediff = 0;
+ #endif
+
++ log_event("FCM<", (u32)host->mrq, (u32)host->cmd);
+ pr_debug("finish_command(%x)\n", bcm2835_sdhost_read(host, SDCMD));
+
+ BUG_ON(!host->cmd || !host->mrq);
+
+-#ifdef DEBUG
+- do_gettimeofday(&before);
+-#endif
+- /* Wait max 100 ms */
+- timeout = 10000;
++ /* Poll quickly at first */
++
++ retries = host->cmd_quick_poll_retries;
++ if (!retries) {
++ /* Work out how many polls take 1us by timing 10us */
++ struct timeval start, now;
++ int us_diff;
++
++ retries = 1;
++ do {
++ int i;
++
++ retries *= 2;
++
++ do_gettimeofday(&start);
++
++ for (i = 0; i < retries; i++) {
++ cpu_relax();
++ sdcmd = bcm2835_sdhost_read(host, SDCMD);
++ }
++
++ do_gettimeofday(&now);
++ us_diff = (now.tv_sec - start.tv_sec) * 1000000 +
++ (now.tv_usec - start.tv_usec);
++ } while (us_diff < 10);
++
++ host->cmd_quick_poll_retries = ((retries * us_diff + 9)*CMD_DALLY_US)/10 + 1;
++ retries = 1; // We've already waited long enough this time
++ }
++
++ retries = host->cmd_quick_poll_retries;
+ for (sdcmd = bcm2835_sdhost_read(host, SDCMD);
+- (sdcmd & SDCMD_NEW_FLAG) && timeout;
+- timeout--) {
+- if (host->flush_fifo) {
+- while (bcm2835_sdhost_read(host, SDHSTS) &
+- SDHSTS_DATA_FLAG)
+- (void)bcm2835_sdhost_read(host, SDDATA);
+- }
+- udelay(10);
++ (sdcmd & SDCMD_NEW_FLAG) && !(sdcmd & SDCMD_FAIL_FLAG) && retries;
++ retries--) {
++ cpu_relax();
+ sdcmd = bcm2835_sdhost_read(host, SDCMD);
+ }
+-#ifdef DEBUG
+- do_gettimeofday(&after);
+- timediff = (after.tv_sec - before.tv_sec)*1000000 +
+- (after.tv_usec - before.tv_usec);
+
+- pr_debug(" finish_command - waited %dus\n", timediff);
+-#endif
++ if (!retries) {
++ unsigned long wait_max;
++
++ if (!irq_flags) {
++ /* Schedule the work */
++ log_event("CWWQ", 0, 0);
++ schedule_work(&host->cmd_wait_wq);
++ return;
++ }
++
++ /* Wait max 100 ms */
++ wait_max = jiffies + msecs_to_jiffies(100);
++ while (time_before(jiffies, wait_max)) {
++ spin_unlock_irqrestore(&host->lock, *irq_flags);
++ usleep_range(1, 10);
++ spin_lock_irqsave(&host->lock, *irq_flags);
++ sdcmd = bcm2835_sdhost_read(host, SDCMD);
++ if (!(sdcmd & SDCMD_NEW_FLAG) ||
++ (sdcmd & SDCMD_FAIL_FLAG))
++ break;
++ }
++ }
+
+- if (timeout == 0) {
++ /* Check for errors */
++ if (sdcmd & SDCMD_NEW_FLAG) {
+ pr_err("%s: command never completed.\n",
+ mmc_hostname(host->mmc));
+ bcm2835_sdhost_dumpregs(host);
+ host->cmd->error = -EIO;
+ tasklet_schedule(&host->finish_tasklet);
+ return;
+- }
+-
+- if (host->flush_fifo) {
+- for (timeout = 100;
+- (bcm2835_sdhost_read(host, SDHSTS) & SDHSTS_DATA_FLAG) && timeout;
+- timeout--) {
+- (void)bcm2835_sdhost_read(host, SDDATA);
+- }
+- host->flush_fifo = 0;
+- if (timeout == 0) {
+- pr_err("%s: FIFO never drained.\n",
+- mmc_hostname(host->mmc));
+- bcm2835_sdhost_dumpregs(host);
+- host->cmd->error = -EIO;
+- tasklet_schedule(&host->finish_tasklet);
+- return;
+- }
+- }
+-
+- /* Check for errors */
+- if (sdcmd & SDCMD_FAIL_FLAG)
+- {
++ } else if (sdcmd & SDCMD_FAIL_FLAG) {
+ u32 sdhsts = bcm2835_sdhost_read(host, SDHSTS);
+
++ /* Clear the errors */
++ bcm2835_sdhost_write(host, SDHSTS_ERROR_MASK, SDHSTS);
++
+ if (host->debug)
+ pr_info("%s: error detected - CMD %x, HSTS %03x, EDM %x\n",
+ mmc_hostname(host->mmc), sdcmd, sdhsts,
+@@ -1003,7 +1197,7 @@ static void bcm2835_sdhost_finish_comman
+ mmc_hostname(host->mmc),
+ host->cmd->opcode);
+ bcm2835_sdhost_dumpregs(host);
+- host->cmd->error = -EIO;
++ host->cmd->error = -EILSEQ;
+ }
+ tasklet_schedule(&host->finish_tasklet);
+ return;
+@@ -1018,31 +1212,31 @@ static void bcm2835_sdhost_finish_comman
+ pr_debug("%s: finish_command %08x %08x %08x %08x\n",
+ mmc_hostname(host->mmc),
+ host->cmd->resp[0], host->cmd->resp[1], host->cmd->resp[2], host->cmd->resp[3]);
++ log_event("RSP ", host->cmd->resp[0], host->cmd->resp[1]);
+ } else {
+ host->cmd->resp[0] = bcm2835_sdhost_read(host, SDRSP0);
+ pr_debug("%s: finish_command %08x\n",
+ mmc_hostname(host->mmc),
+ host->cmd->resp[0]);
++ log_event("RSP ", host->cmd->resp[0], 0);
+ }
+ }
+
+- host->cmd->error = 0;
+-
+ if (host->cmd == host->mrq->sbc) {
+ /* Finished CMD23, now send actual command. */
+ host->cmd = NULL;
+- bcm2835_sdhost_send_command(host, host->mrq->cmd);
++ if (bcm2835_sdhost_send_command(host, host->mrq->cmd)) {
++ if (host->data && host->dma_desc)
++ /* DMA transfer starts now, PIO starts after irq */
++ bcm2835_sdhost_start_dma(host);
+
+- if (host->cmd->data && host->use_dma)
+- /* DMA transfer starts now, PIO starts after irq */
+- bcm2835_sdhost_transfer_dma(host);
+-
+- if (!host->use_busy)
+- bcm2835_sdhost_finish_command(host);
+- } else if (host->cmd == host->mrq->stop)
++ if (!host->use_busy)
++ bcm2835_sdhost_finish_command(host, NULL);
++ }
++ } else if (host->cmd == host->mrq->stop) {
+ /* Finished CMD12 */
+ tasklet_schedule(&host->finish_tasklet);
+- else {
++ } else {
+ /* Processed actual command. */
+ host->cmd = NULL;
+ if (!host->data)
+@@ -1050,6 +1244,7 @@ static void bcm2835_sdhost_finish_comman
+ else if (host->data_complete)
+ bcm2835_sdhost_transfer_complete(host);
+ }
++ log_event("FCM>", (u32)host->mrq, (u32)host->cmd);
+ }
+
+ static void bcm2835_sdhost_timeout(unsigned long data)
+@@ -1060,10 +1255,12 @@ static void bcm2835_sdhost_timeout(unsig
+ host = (struct bcm2835_host *)data;
+
+ spin_lock_irqsave(&host->lock, flags);
++ log_event("TIM<", 0, 0);
+
+ if (host->mrq) {
+ pr_err("%s: timeout waiting for hardware interrupt.\n",
+ mmc_hostname(host->mmc));
++ log_dump();
+ bcm2835_sdhost_dumpregs(host);
+
+ if (host->data) {
+@@ -1084,74 +1281,15 @@ static void bcm2835_sdhost_timeout(unsig
+ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+-static void bcm2835_sdhost_pio_timeout(unsigned long data)
+-{
+- struct bcm2835_host *host;
+- unsigned long flags;
+-
+- host = (struct bcm2835_host *)data;
+-
+- spin_lock_irqsave(&host->lock, flags);
+-
+- if (host->data) {
+- u32 sdhsts = bcm2835_sdhost_read(host, SDHSTS);
+-
+- if (sdhsts & SDHSTS_REW_TIME_OUT) {
+- pr_err("%s: transfer timeout\n",
+- mmc_hostname(host->mmc));
+- if (host->debug)
+- bcm2835_sdhost_dumpregs(host);
+- } else {
+- pr_err("%s: unexpected transfer timeout\n",
+- mmc_hostname(host->mmc));
+- bcm2835_sdhost_dumpregs(host);
+- }
+-
+- bcm2835_sdhost_write(host, SDHSTS_TRANSFER_ERROR_MASK,
+- SDHSTS);
+-
+- host->data->error = -ETIMEDOUT;
+-
+- bcm2835_sdhost_finish_data(host);
+- }
+-
+- mmiowb();
+- spin_unlock_irqrestore(&host->lock, flags);
+-}
+-
+-static void bcm2835_sdhost_enable_sdio_irq_nolock(struct bcm2835_host *host, int enable)
+-{
+- if (enable)
+- host->hcfg |= SDHCFG_SDIO_IRPT_EN;
+- else
+- host->hcfg &= ~SDHCFG_SDIO_IRPT_EN;
+- bcm2835_sdhost_write(host, host->hcfg, SDHCFG);
+- mmiowb();
+-}
+-
+-static void bcm2835_sdhost_enable_sdio_irq(struct mmc_host *mmc, int enable)
+-{
+- struct bcm2835_host *host = mmc_priv(mmc);
+- unsigned long flags;
+-
+- pr_debug("%s: enable_sdio_irq(%d)\n", mmc_hostname(mmc), enable);
+- spin_lock_irqsave(&host->lock, flags);
+- bcm2835_sdhost_enable_sdio_irq_nolock(host, enable);
+- spin_unlock_irqrestore(&host->lock, flags);
+-}
+-
+-static u32 bcm2835_sdhost_busy_irq(struct bcm2835_host *host, u32 intmask)
++static void bcm2835_sdhost_busy_irq(struct bcm2835_host *host, u32 intmask)
+ {
+- const u32 handled = (SDHSTS_REW_TIME_OUT | SDHSTS_CMD_TIME_OUT |
+- SDHSTS_CRC16_ERROR | SDHSTS_CRC7_ERROR |
+- SDHSTS_FIFO_ERROR);
+-
++ log_event("IRQB", (u32)host->cmd, intmask);
+ if (!host->cmd) {
+ pr_err("%s: got command busy interrupt 0x%08x even "
+ "though no command operation was in progress.\n",
+ mmc_hostname(host->mmc), (unsigned)intmask);
+ bcm2835_sdhost_dumpregs(host);
+- return 0;
++ return;
+ }
+
+ if (!host->use_busy) {
+@@ -1159,7 +1297,7 @@ static u32 bcm2835_sdhost_busy_irq(struc
+ "though not expecting one.\n",
+ mmc_hostname(host->mmc), (unsigned)intmask);
+ bcm2835_sdhost_dumpregs(host);
+- return 0;
++ return;
+ }
+ host->use_busy = 0;
+
+@@ -1182,28 +1320,23 @@ static u32 bcm2835_sdhost_busy_irq(struc
+ } else if (intmask & SDHSTS_CMD_TIME_OUT)
+ host->cmd->error = -ETIMEDOUT;
+
++ log_dump();
+ bcm2835_sdhost_dumpregs(host);
+- tasklet_schedule(&host->finish_tasklet);
+ }
+ else
+- bcm2835_sdhost_finish_command(host);
+-
+- return handled;
++ bcm2835_sdhost_finish_command(host, NULL);
+ }
+
+-static u32 bcm2835_sdhost_data_irq(struct bcm2835_host *host, u32 intmask)
++static void bcm2835_sdhost_data_irq(struct bcm2835_host *host, u32 intmask)
+ {
+- const u32 handled = (SDHSTS_REW_TIME_OUT |
+- SDHSTS_CRC16_ERROR |
+- SDHSTS_FIFO_ERROR);
+-
+ /* There are no dedicated data/space available interrupt
+ status bits, so it is necessary to use the single shared
+ data/space available FIFO status bits. It is therefore not
+ an error to get here when there is no data transfer in
+ progress. */
++ log_event("IRQD", (u32)host->data, intmask);
+ if (!host->data)
+- return 0;
++ return;
+
+ if (intmask & (SDHSTS_CRC16_ERROR |
+ SDHSTS_FIFO_ERROR |
+@@ -1214,46 +1347,37 @@ static u32 bcm2835_sdhost_data_irq(struc
+ else
+ host->data->error = -ETIMEDOUT;
+
+- bcm2835_sdhost_dumpregs(host);
+- tasklet_schedule(&host->finish_tasklet);
+- return handled;
++ if (host->debug) {
++ log_dump();
++ bcm2835_sdhost_dumpregs(host);
++ }
+ }
+
+- /* Use the block interrupt for writes after the first block */
+- if (host->data->flags & MMC_DATA_WRITE) {
++ if (host->data->error) {
++ bcm2835_sdhost_finish_data(host);
++ } else if (host->data->flags & MMC_DATA_WRITE) {
++ /* Use the block interrupt for writes after the first block */
+ host->hcfg &= ~(SDHCFG_DATA_IRPT_EN);
+ host->hcfg |= SDHCFG_BLOCK_IRPT_EN;
+ bcm2835_sdhost_write(host, host->hcfg, SDHCFG);
+- if (host->data->error)
+- bcm2835_sdhost_finish_data(host);
+- else
+- bcm2835_sdhost_transfer_pio(host);
++ bcm2835_sdhost_transfer_pio(host);
+ } else {
+- if (!host->data->error) {
+- bcm2835_sdhost_transfer_pio(host);
+- host->blocks--;
+- }
++ bcm2835_sdhost_transfer_pio(host);
++ host->blocks--;
+ if ((host->blocks == 0) || host->data->error)
+ bcm2835_sdhost_finish_data(host);
+ }
+-
+- return handled;
+ }
+
+-static u32 bcm2835_sdhost_block_irq(struct bcm2835_host *host, u32 intmask)
++static void bcm2835_sdhost_block_irq(struct bcm2835_host *host, u32 intmask)
+ {
+- struct dma_chan *dma_chan;
+- u32 dir_data;
+- const u32 handled = (SDHSTS_REW_TIME_OUT |
+- SDHSTS_CRC16_ERROR |
+- SDHSTS_FIFO_ERROR);
+-
++ log_event("IRQK", (u32)host->data, intmask);
+ if (!host->data) {
+ pr_err("%s: got block interrupt 0x%08x even "
+ "though no data operation was in progress.\n",
+ mmc_hostname(host->mmc), (unsigned)intmask);
+ bcm2835_sdhost_dumpregs(host);
+- return handled;
++ return;
+ }
+
+ if (intmask & (SDHSTS_CRC16_ERROR |
+@@ -1265,149 +1389,69 @@ static u32 bcm2835_sdhost_block_irq(stru
+ else
+ host->data->error = -ETIMEDOUT;
+
+- if (host->debug)
++ if (host->debug) {
++ log_dump();
+ bcm2835_sdhost_dumpregs(host);
+- tasklet_schedule(&host->finish_tasklet);
+- return handled;
++ }
+ }
+
+- if (!host->use_dma) {
++ if (!host->dma_desc) {
+ BUG_ON(!host->blocks);
+- host->blocks--;
+- if ((host->blocks == 0) || host->data->error) {
+- /* Cancel the timer */
+- del_timer(&host->pio_timer);
+-
++ if (host->data->error || (--host->blocks == 0)) {
+ bcm2835_sdhost_finish_data(host);
+ } else {
+- /* Reset the timer */
+- mod_timer(&host->pio_timer,
+- jiffies + host->pio_timeout);
+-
+ bcm2835_sdhost_transfer_pio(host);
+-
+- /* Reset the timer */
+- mod_timer(&host->pio_timer,
+- jiffies + host->pio_timeout);
+ }
+ } else if (host->data->flags & MMC_DATA_WRITE) {
+- dma_chan = host->dma_chan_tx;
+- dir_data = DMA_TO_DEVICE;
+- dma_unmap_sg(dma_chan->device->dev,
+- host->data->sg, host->data->sg_len,
+- dir_data);
+-
+ bcm2835_sdhost_finish_data(host);
+ }
+-
+- return handled;
+ }
+
+-
+ static irqreturn_t bcm2835_sdhost_irq(int irq, void *dev_id)
+ {
+ irqreturn_t result = IRQ_NONE;
+ struct bcm2835_host *host = dev_id;
+- u32 unexpected = 0, early = 0;
+- int loops = 0;
++ u32 intmask;
+
+ spin_lock(&host->lock);
+
+- for (loops = 0; loops < 1; loops++) {
+- u32 intmask, handled;
+-
+- intmask = bcm2835_sdhost_read(host, SDHSTS);
+- handled = intmask & (SDHSTS_BUSY_IRPT |
+- SDHSTS_BLOCK_IRPT |
+- SDHSTS_SDIO_IRPT |
+- SDHSTS_DATA_FLAG);
+- if ((handled == SDHSTS_DATA_FLAG) &&
+- (loops == 0) && !host->data) {
+- pr_err("%s: sdhost_irq data interrupt 0x%08x even "
+- "though no data operation was in progress.\n",
+- mmc_hostname(host->mmc),
+- (unsigned)intmask);
+-
+- bcm2835_sdhost_dumpregs(host);
+- }
+-
+- if (!handled)
+- break;
++ intmask = bcm2835_sdhost_read(host, SDHSTS);
++ log_event("IRQ<", intmask, 0);
+
+- if (loops)
+- early |= handled;
++ bcm2835_sdhost_write(host,
++ SDHSTS_BUSY_IRPT |
++ SDHSTS_BLOCK_IRPT |
++ SDHSTS_SDIO_IRPT |
++ SDHSTS_DATA_FLAG,
++ SDHSTS);
+
++ if (intmask & SDHSTS_BLOCK_IRPT) {
++ bcm2835_sdhost_block_irq(host, intmask);
+ result = IRQ_HANDLED;
++ }
+
+- /* Clear all interrupts and notifications */
+- bcm2835_sdhost_write(host, intmask, SDHSTS);
+-
+- if (intmask & SDHSTS_BUSY_IRPT)
+- handled |= bcm2835_sdhost_busy_irq(host, intmask);
+-
+- /* There is no true data interrupt status bit, so it is
+- necessary to qualify the data flag with the interrupt
+- enable bit */
+- if ((intmask & SDHSTS_DATA_FLAG) &&
+- (host->hcfg & SDHCFG_DATA_IRPT_EN))
+- handled |= bcm2835_sdhost_data_irq(host, intmask);
+-
+- if (intmask & SDHSTS_BLOCK_IRPT)
+- handled |= bcm2835_sdhost_block_irq(host, intmask);
+-
+- if (intmask & SDHSTS_SDIO_IRPT) {
+- bcm2835_sdhost_enable_sdio_irq_nolock(host, false);
+- host->thread_isr |= SDHSTS_SDIO_IRPT;
+- result = IRQ_WAKE_THREAD;
+- }
++ if (intmask & SDHSTS_BUSY_IRPT) {
++ bcm2835_sdhost_busy_irq(host, intmask);
++ result = IRQ_HANDLED;
++ }
+
+- unexpected |= (intmask & ~handled);
++ /* There is no true data interrupt status bit, so it is
++ necessary to qualify the data flag with the interrupt
++ enable bit */
++ if ((intmask & SDHSTS_DATA_FLAG) &&
++ (host->hcfg & SDHCFG_DATA_IRPT_EN)) {
++ bcm2835_sdhost_data_irq(host, intmask);
++ result = IRQ_HANDLED;
+ }
+
+ mmiowb();
+
++ log_event("IRQ>", bcm2835_sdhost_read(host, SDHSTS), 0);
+ spin_unlock(&host->lock);
+
+- if (early)
+- pr_debug("%s: early %x (loops %d)\n",
+- mmc_hostname(host->mmc), early, loops);
+-
+- if (unexpected) {
+- pr_err("%s: unexpected interrupt 0x%08x.\n",
+- mmc_hostname(host->mmc), unexpected);
+- bcm2835_sdhost_dumpregs(host);
+- }
+-
+ return result;
+ }
+
+-static irqreturn_t bcm2835_sdhost_thread_irq(int irq, void *dev_id)
+-{
+- struct bcm2835_host *host = dev_id;
+- unsigned long flags;
+- u32 isr;
+-
+- spin_lock_irqsave(&host->lock, flags);
+- isr = host->thread_isr;
+- host->thread_isr = 0;
+- spin_unlock_irqrestore(&host->lock, flags);
+-
+- if (isr & SDHSTS_SDIO_IRPT) {
+- sdio_run_irqs(host->mmc);
+-
+-/* Is this necessary? Why re-enable an interrupt which is enabled?
+- spin_lock_irqsave(&host->lock, flags);
+- if (host->flags & SDHSTS_SDIO_IRPT_ENABLED)
+- bcm2835_sdhost_enable_sdio_irq_nolock(host, true);
+- spin_unlock_irqrestore(&host->lock, flags);
+-*/
+- }
+-
+- return isr ? IRQ_HANDLED : IRQ_NONE;
+-}
+-
+-
+-
+ void bcm2835_sdhost_set_clock(struct bcm2835_host *host, unsigned int clock)
+ {
+ int div = 0; /* Initialized for compiler warning */
+@@ -1417,9 +1461,8 @@ void bcm2835_sdhost_set_clock(struct bcm
+ pr_info("%s: set_clock(%d)\n", mmc_hostname(host->mmc), clock);
+
+ if ((host->overclock_50 > 50) &&
+- (clock == 50*MHZ)) {
++ (clock == 50*MHZ))
+ clock = host->overclock_50 * MHZ + (MHZ - 1);
+- }
+
+ /* The SDCDIV register has 11 bits, and holds (div - 2).
+ But in data mode the max is 50MHz wihout a minimum, and only the
+@@ -1466,6 +1509,11 @@ void bcm2835_sdhost_set_clock(struct bcm
+ clock = host->max_clk / (div + 2);
+ host->mmc->actual_clock = clock;
+
++ /* Calibrate some delays */
++
++ host->ns_per_fifo_word = (1000000000/clock) *
++ ((host->mmc->caps & MMC_CAP_4_BIT_DATA) ? 8 : 32);
++
+ if (clock > input_clock) {
+ /* Save the closest value, to make it easier
+ to reduce in the event of error */
+@@ -1501,6 +1549,7 @@ static void bcm2835_sdhost_request(struc
+ {
+ struct bcm2835_host *host;
+ unsigned long flags;
++ u32 edm, fsm;
+
+ host = mmc_priv(mmc);
+
+@@ -1521,6 +1570,8 @@ static void bcm2835_sdhost_request(struc
+ }
+
+ /* Reset the error statuses in case this is a retry */
++ if (mrq->sbc)
++ mrq->sbc->error = 0;
+ if (mrq->cmd)
+ mrq->cmd->error = 0;
+ if (mrq->data)
+@@ -1536,28 +1587,58 @@ static void bcm2835_sdhost_request(struc
+ return;
+ }
+
++ if (host->use_dma && mrq->data &&
++ (mrq->data->blocks > host->pio_limit))
++ bcm2835_sdhost_prepare_dma(host, mrq->data);
++
+ spin_lock_irqsave(&host->lock, flags);
+
+ WARN_ON(host->mrq != NULL);
+-
+ host->mrq = mrq;
+
+- if (mrq->sbc)
+- bcm2835_sdhost_send_command(host, mrq->sbc);
+- else
+- bcm2835_sdhost_send_command(host, mrq->cmd);
++ edm = bcm2835_sdhost_read(host, SDEDM);
++ fsm = edm & SDEDM_FSM_MASK;
+
+- mmiowb();
+- spin_unlock_irqrestore(&host->lock, flags);
++ log_event("REQ<", (u32)mrq, edm);
++ if ((fsm != SDEDM_FSM_IDENTMODE) &&
++ (fsm != SDEDM_FSM_DATAMODE)) {
++ pr_err("%s: previous command (%d) not complete (EDM %x)\n",
++ mmc_hostname(host->mmc),
++ bcm2835_sdhost_read(host, SDCMD) & SDCMD_CMD_MASK,
++ edm);
++ log_event("REQ!", (u32)mrq, edm);
++ log_dump();
++ bcm2835_sdhost_dumpregs(host);
++ mrq->cmd->error = -EILSEQ;
++ tasklet_schedule(&host->finish_tasklet);
++ mmiowb();
++ spin_unlock_irqrestore(&host->lock, flags);
++ return;
++ }
++
++ host->use_sbc = !!mrq->sbc &&
++ (host->mrq->data->flags & USE_CMD23_FLAGS);
++ if (host->use_sbc) {
++ if (bcm2835_sdhost_send_command(host, mrq->sbc)) {
++ if (!host->use_busy)
++ bcm2835_sdhost_finish_command(host, &flags);
++ }
++ } else if (bcm2835_sdhost_send_command(host, mrq->cmd)) {
++ if (host->data && host->dma_desc)
++ /* DMA transfer starts now, PIO starts after irq */
++ bcm2835_sdhost_start_dma(host);
+
+- if (!mrq->sbc && mrq->cmd->data && host->use_dma)
+- /* DMA transfer starts now, PIO starts after irq */
+- bcm2835_sdhost_transfer_dma(host);
++ if (!host->use_busy)
++ bcm2835_sdhost_finish_command(host, &flags);
++ }
+
+- if (!host->use_busy)
+- bcm2835_sdhost_finish_command(host);
+-}
++ log_event("CMD ", (u32)mrq->cmd->opcode,
++ mrq->data ? (u32)mrq->data->blksz : 0);
++ mmiowb();
+
++ log_event("REQ>", (u32)mrq, 0);
++ spin_unlock_irqrestore(&host->lock, flags);
++}
+
+ static void bcm2835_sdhost_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
+ {
+@@ -1574,6 +1655,8 @@ static void bcm2835_sdhost_set_ios(struc
+
+ spin_lock_irqsave(&host->lock, flags);
+
++ log_event("IOS<", ios->clock, 0);
++
+ if (!ios->clock || ios->clock != host->clock) {
+ bcm2835_sdhost_set_clock(host, ios->clock);
+ host->clock = ios->clock;
+@@ -1596,59 +1679,53 @@ static void bcm2835_sdhost_set_ios(struc
+ spin_unlock_irqrestore(&host->lock, flags);
+ }
+
+-static int bcm2835_sdhost_multi_io_quirk(struct mmc_card *card,
+- unsigned int direction,
+- u32 blk_pos, int blk_size)
+-{
+- /* There is a bug in the host controller hardware that makes
+- reading the final sector of the card as part of a multiple read
+- problematic. Detect that case and shorten the read accordingly.
+- */
++static struct mmc_host_ops bcm2835_sdhost_ops = {
++ .request = bcm2835_sdhost_request,
++ .set_ios = bcm2835_sdhost_set_ios,
++ .hw_reset = bcm2835_sdhost_reset,
++};
++
++static void bcm2835_sdhost_cmd_wait_work(struct work_struct *work)
++{
+ struct bcm2835_host *host;
++ unsigned long flags;
+
+- host = mmc_priv(card->host);
++ host = container_of(work, struct bcm2835_host, cmd_wait_wq);
+
+- if (!host->sectors) {
+- /* csd.capacity is in weird units - convert to sectors */
+- u32 card_sectors = (card->csd.capacity << (card->csd.read_blkbits - 9));
+- if ((direction == MMC_DATA_READ) &&
+- ((blk_pos + blk_size) == card_sectors))
+- blk_size--;
+- return blk_size;
+- }
++ spin_lock_irqsave(&host->lock, flags);
+
+- if (direction == MMC_DATA_READ) {
+- int i;
+- int sector;
+- for (i = 0; blk_pos > (sector = host->single_read_sectors[i]); i++)
+- continue;
++ log_event("CWK<", (u32)host->cmd, (u32)host->mrq);
+
+- if ((blk_pos + blk_size) > sector)
+- blk_size = (blk_pos == sector) ? 1 : (sector - blk_pos);
++ /*
++ * If this tasklet gets rescheduled while running, it will
++ * be run again afterwards but without any active request.
++ */
++ if (!host->mrq) {
++ spin_unlock_irqrestore(&host->lock, flags);
++ return;
+ }
+- return blk_size;
+-}
+
++ bcm2835_sdhost_finish_command(host, &flags);
+
+-static struct mmc_host_ops bcm2835_sdhost_ops = {
+- .request = bcm2835_sdhost_request,
+- .set_ios = bcm2835_sdhost_set_ios,
+- .enable_sdio_irq = bcm2835_sdhost_enable_sdio_irq,
+- .hw_reset = bcm2835_sdhost_reset,
+- .multi_io_quirk = bcm2835_sdhost_multi_io_quirk,
+-};
++ mmiowb();
++
++ log_event("CWK>", (u32)host->cmd, 0);
+
++ spin_unlock_irqrestore(&host->lock, flags);
++}
+
+ static void bcm2835_sdhost_tasklet_finish(unsigned long param)
+ {
+ struct bcm2835_host *host;
+ unsigned long flags;
+ struct mmc_request *mrq;
++ struct dma_chan *terminate_chan = NULL;
+
+ host = (struct bcm2835_host *)param;
+
+ spin_lock_irqsave(&host->lock, flags);
+
++ log_event("TSK<", (u32)host->mrq, 0);
+ /*
+ * If this tasklet gets rescheduled while running, it will
+ * be run again afterwards but without any active request.
+@@ -1683,11 +1760,23 @@ static void bcm2835_sdhost_tasklet_finis
+
+ mmiowb();
+
++ host->dma_desc = NULL;
++ terminate_chan = host->dma_chan;
++ host->dma_chan = NULL;
++
+ spin_unlock_irqrestore(&host->lock, flags);
+- mmc_request_done(host->mmc, mrq);
+-}
+
++ if (terminate_chan)
++ {
++ int err = dmaengine_terminate_all(terminate_chan);
++ if (err)
++ pr_err("%s: failed to terminate DMA (%d)\n",
++ mmc_hostname(host->mmc), err);
++ }
+
++ mmc_request_done(host->mmc, mrq);
++ log_event("TSK>", (u32)mrq, 0);
++}
+
+ int bcm2835_sdhost_add_host(struct bcm2835_host *host)
+ {
+@@ -1709,10 +1798,10 @@ int bcm2835_sdhost_add_host(struct bcm28
+ mmc->f_max, mmc->f_min, mmc->max_busy_timeout);
+
+ /* host controller capabilities */
+- mmc->caps |= /* MMC_CAP_SDIO_IRQ |*/ MMC_CAP_4_BIT_DATA |
++ mmc->caps |=
+ MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
+ MMC_CAP_NEEDS_POLL | MMC_CAP_HW_RESET | MMC_CAP_ERASE |
+- (ALLOW_CMD23 * MMC_CAP_CMD23);
++ ((ALLOW_CMD23_READ|ALLOW_CMD23_WRITE) * MMC_CAP_CMD23);
+
+ spin_lock_init(&host->lock);
+
+@@ -1722,9 +1811,9 @@ int bcm2835_sdhost_add_host(struct bcm28
+ pr_err("%s: unable to initialise DMA channels. "
+ "Falling back to PIO\n",
+ mmc_hostname(mmc));
+- host->have_dma = false;
++ host->use_dma = false;
+ } else {
+- host->have_dma = true;
++ host->use_dma = true;
+
+ cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+@@ -1741,7 +1830,7 @@ int bcm2835_sdhost_add_host(struct bcm28
+ ret = dmaengine_slave_config(host->dma_chan_rx, &cfg);
+ }
+ } else {
+- host->have_dma = false;
++ host->use_dma = false;
+ }
+
+ mmc->max_segs = 128;
+@@ -1756,16 +1845,15 @@ int bcm2835_sdhost_add_host(struct bcm28
+ tasklet_init(&host->finish_tasklet,
+ bcm2835_sdhost_tasklet_finish, (unsigned long)host);
+
+- setup_timer(&host->timer, bcm2835_sdhost_timeout,
+- (unsigned long)host);
++ INIT_WORK(&host->cmd_wait_wq, bcm2835_sdhost_cmd_wait_work);
+
+- setup_timer(&host->pio_timer, bcm2835_sdhost_pio_timeout,
++ setup_timer(&host->timer, bcm2835_sdhost_timeout,
+ (unsigned long)host);
+
+ bcm2835_sdhost_init(host, 0);
+- ret = request_threaded_irq(host->irq, bcm2835_sdhost_irq,
+- bcm2835_sdhost_thread_irq,
+- IRQF_SHARED, mmc_hostname(mmc), host);
++
++ ret = request_irq(host->irq, bcm2835_sdhost_irq, 0 /*IRQF_SHARED*/,
++ mmc_hostname(mmc), host);
+ if (ret) {
+ pr_err("%s: failed to request IRQ %d: %d\n",
+ mmc_hostname(mmc), host->irq, ret);
+@@ -1776,11 +1864,11 @@ int bcm2835_sdhost_add_host(struct bcm28
+ mmc_add_host(mmc);
+
+ pio_limit_string[0] = '\0';
+- if (host->have_dma && (host->pio_limit > 0))
++ if (host->use_dma && (host->pio_limit > 0))
+ sprintf(pio_limit_string, " (>%d)", host->pio_limit);
+ pr_info("%s: %s loaded - DMA %s%s\n",
+ mmc_hostname(mmc), DRIVER_NAME,
+- host->have_dma ? "enabled" : "disabled",
++ host->use_dma ? "enabled" : "disabled",
+ pio_limit_string);
+
+ return 0;
+@@ -1810,8 +1898,11 @@ static int bcm2835_sdhost_probe(struct p
+ mmc->ops = &bcm2835_sdhost_ops;
+ host = mmc_priv(mmc);
+ host->mmc = mmc;
++ host->cmd_quick_poll_retries = 0;
+ host->pio_timeout = msecs_to_jiffies(500);
++ host->pio_limit = 1;
+ host->max_delay = 1; /* Warn if over 1ms */
++ host->allow_dma = 1;
+ spin_lock_init(&host->lock);
+
+ iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+@@ -1827,13 +1918,12 @@ static int bcm2835_sdhost_probe(struct p
+ return -ENODEV;
+ }
+ host->bus_addr = be32_to_cpup(addr);
++ log_init(iomem->start - host->bus_addr);
+ pr_debug(" - ioaddr %lx, iomem->start %lx, bus_addr %lx\n",
+ (unsigned long)host->ioaddr,
+ (unsigned long)iomem->start,
+ (unsigned long)host->bus_addr);
+
+- host->allow_dma = ALLOW_DMA;
+-
+ if (node) {
+ /* Read any custom properties */
+ of_property_read_u32(node,
+@@ -1845,16 +1935,17 @@ static int bcm2835_sdhost_probe(struct p
+ of_property_read_u32(node,
+ "brcm,pio-limit",
+ &host->pio_limit);
+- host->allow_dma = ALLOW_DMA &&
++ host->allow_dma =
+ !of_property_read_bool(node, "brcm,force-pio");
+ host->debug = of_property_read_bool(node, "brcm,debug");
+- of_property_read_u32(node,
+- "brcm,debug-flags",
+- &host->debug_flags);
+ }
+
+- if (host->debug_flags)
+- dev_err(dev, "debug_flags=%x\n", host->debug_flags);
++ host->dma_chan = NULL;
++ host->dma_desc = NULL;
++
++ /* Formally recognise the other way of disabling DMA */
++ if (host->pio_limit == 0x7fffffff)
++ host->allow_dma = false;
+
+ if (host->allow_dma) {
+ if (node) {
+@@ -1940,15 +2031,12 @@ static int bcm2835_sdhost_remove(struct
+ return 0;
+ }
+
+-
+ static const struct of_device_id bcm2835_sdhost_match[] = {
+ { .compatible = "brcm,bcm2835-sdhost" },
+ { }
+ };
+ MODULE_DEVICE_TABLE(of, bcm2835_sdhost_match);
+
+-
+-
+ static struct platform_driver bcm2835_sdhost_driver = {
+ .probe = bcm2835_sdhost_probe,
+ .remove = bcm2835_sdhost_remove,