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Diffstat (limited to 'target/linux/mvebu/patches-3.18/019-mtd-nand-pxa3xx-Fix-PIO-FIFO-draining.patch')
-rw-r--r--target/linux/mvebu/patches-3.18/019-mtd-nand-pxa3xx-Fix-PIO-FIFO-draining.patch97
1 files changed, 97 insertions, 0 deletions
diff --git a/target/linux/mvebu/patches-3.18/019-mtd-nand-pxa3xx-Fix-PIO-FIFO-draining.patch b/target/linux/mvebu/patches-3.18/019-mtd-nand-pxa3xx-Fix-PIO-FIFO-draining.patch
new file mode 100644
index 0000000..bf20069
--- /dev/null
+++ b/target/linux/mvebu/patches-3.18/019-mtd-nand-pxa3xx-Fix-PIO-FIFO-draining.patch
@@ -0,0 +1,97 @@
+From 11aa9df4de06cc257327d783c5cb615989e87286 Mon Sep 17 00:00:00 2001
+From: Maxime Ripard <maxime.ripard@free-electrons.com>
+Date: Fri, 23 Jan 2015 15:18:27 +0100
+Subject: [PATCH v2 1/2] mtd: nand: pxa3xx: Fix PIO FIFO draining
+
+The NDDB register holds the data that are needed by the read and write
+commands.
+
+However, during a read PIO access, the datasheet specifies that after each 32
+bits read in that register, when BCH is enabled, we have to make sure that the
+RDDREQ bit is set in the NDSR register.
+
+This fixes an issue that was seen on the Armada 385, and presumably other mvebu
+SoCs, when a read on a newly erased page would end up in the driver reporting a
+timeout from the NAND.
+
+Cc: <stable@vger.kernel.org> # v3.14
+Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
+---
+ drivers/mtd/nand/pxa3xx_nand.c | 45 ++++++++++++++++++++++++++++++++++++------
+ 1 file changed, 39 insertions(+), 6 deletions(-)
+
+diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c
+index 96b0b1d27df1..e6918befb951 100644
+--- a/drivers/mtd/nand/pxa3xx_nand.c
++++ b/drivers/mtd/nand/pxa3xx_nand.c
+@@ -23,6 +23,7 @@
+ #include <linux/mtd/partitions.h>
+ #include <linux/io.h>
+ #include <linux/irq.h>
++#include <linux/jiffies.h>
+ #include <linux/slab.h>
+ #include <linux/of.h>
+ #include <linux/of_device.h>
+@@ -480,6 +481,38 @@ static void disable_int(struct pxa3xx_nand_info *info, uint32_t int_mask)
+ nand_writel(info, NDCR, ndcr | int_mask);
+ }
+
++static void drain_fifo(struct pxa3xx_nand_info *info, void *data, int len)
++{
++ u32 *dst = (u32 *)data;
++
++ if (info->ecc_bch) {
++ while (len--) {
++ u32 timeout;
++
++ *dst++ = nand_readl(info, NDDB);
++
++ /*
++ * According to the datasheet, when reading
++ * from NDDB with BCH enabled, after each 32
++ * bits reads, we have to make sure that the
++ * NDSR.RDDREQ bit is set
++ */
++ timeout = jiffies + msecs_to_jiffies(5);
++ while (!(nand_readl(info, NDSR) & NDSR_RDDREQ)) {
++ if (!time_before(jiffies, timeout)) {
++ dev_err(&info->pdev->dev,
++ "Timeout on RDDREQ while draining the FIFO\n");
++ return;
++ }
++
++ cpu_relax();
++ }
++ }
++ } else {
++ __raw_readsl(info->mmio_base + NDDB, data, len);
++ }
++}
++
+ static void handle_data_pio(struct pxa3xx_nand_info *info)
+ {
+ unsigned int do_bytes = min(info->data_size, info->chunk_size);
+@@ -496,14 +529,14 @@ static void handle_data_pio(struct pxa3xx_nand_info *info)
+ DIV_ROUND_UP(info->oob_size, 4));
+ break;
+ case STATE_PIO_READING:
+- __raw_readsl(info->mmio_base + NDDB,
+- info->data_buff + info->data_buff_pos,
+- DIV_ROUND_UP(do_bytes, 4));
++ drain_fifo(info,
++ info->data_buff + info->data_buff_pos,
++ DIV_ROUND_UP(do_bytes, 4));
+
+ if (info->oob_size > 0)
+- __raw_readsl(info->mmio_base + NDDB,
+- info->oob_buff + info->oob_buff_pos,
+- DIV_ROUND_UP(info->oob_size, 4));
++ drain_fifo(info,
++ info->oob_buff + info->oob_buff_pos,
++ DIV_ROUND_UP(info->oob_size, 4));
+ break;
+ default:
+ dev_err(&info->pdev->dev, "%s: invalid state %d\n", __func__,
+--
+2.2.2
+