From 148f77310a9ddf4db5036066458d7aed92cea9ae Mon Sep 17 00:00:00 2001
From: Andy Gross <andy.gross@linaro.org>
Date: Sun, 31 Jan 2016 21:28:13 -0600
Subject: [PATCH] spi: qup: Fix block mode to work correctly
This patch corrects the behavior of the BLOCK
transactions. During block transactions, the controller
must be read/written to in block size transactions.
Signed-off-by: Andy Gross <andy.gross@linaro.org>
Change-Id: I4b4f4d25be57e6e8148f6f0d24bed376eb287ecf
---
drivers/spi/spi-qup.c | 181 +++++++++++++++++++++++++++++++++++++++-----------
1 file changed, 141 insertions(+), 40 deletions(-)
--- a/drivers/spi/spi-qup.c
+++ b/drivers/spi/spi-qup.c
@@ -83,6 +83,8 @@
#define QUP_IO_M_MODE_BAM 3
/* QUP_OPERATIONAL fields */
+#define QUP_OP_IN_BLOCK_READ_REQ BIT(13)
+#define QUP_OP_OUT_BLOCK_WRITE_REQ BIT(12)
#define QUP_OP_MAX_INPUT_DONE_FLAG BIT(11)
#define QUP_OP_MAX_OUTPUT_DONE_FLAG BIT(10)
#define QUP_OP_IN_SERVICE_FLAG BIT(9)
@@ -156,6 +158,12 @@ struct spi_qup {
struct dma_slave_config tx_conf;
};
+static inline bool spi_qup_is_flag_set(struct spi_qup *controller, u32 flag)
+{
+ u32 opflag = readl_relaxed(controller->base + QUP_OPERATIONAL);
+
+ return opflag & flag;
+}
static inline bool spi_qup_is_dma_xfer(int mode)
{
@@ -217,29 +225,26 @@ static int spi_qup_set_state(struct spi_
return 0;
}
-static void spi_qup_fifo_read(struct spi_qup *controller,
- struct spi_transfer *xfer)
+static void spi_qup_read_from_fifo(struct spi_qup *controller,
+ struct spi_transfer *xfer, u32 num_words)
{
u8 *rx_buf = xfer->rx_buf;
- u32 word, state;
- int idx, shift, w_size;
-
- w_size = controller->w_size;
+ int i, shift, num_bytes;
+ u32 word;
- while (controller->rx_bytes < xfer->len) {
-
- state = readl_relaxed(controller->base + QUP_OPERATIONAL);
- if (0 == (state & QUP_OP_IN_FIFO_NOT_EMPTY))
- break;
+ for (; num_words; num_words--) {
word = readl_relaxed(controller->base + QUP_INPUT_FIFO);
+ num_bytes = min_t(int, xfer->len - controller->rx_bytes,
+ controller->w_size);
+
if (!rx_buf) {
- controller->rx_bytes += w_size;
+ controller->rx_bytes += num_bytes;
continue;
}
- for (idx = 0; idx < w_size; idx++, controller->rx_bytes++) {
+ for (i = 0; i < num_bytes; i++, controller->rx_bytes++) {
/*
* The data format depends on bytes per SPI word:
* 4 bytes: 0x12345678
@@ -247,38 +252,80 @@ static void spi_qup_fifo_read(struct spi
* 1 byte : 0x00000012
*/
shift = BITS_PER_BYTE;
- shift *= (w_size - idx - 1);
+ shift *= (controller->w_size - i - 1);
rx_buf[controller->rx_bytes] = word >> shift;
}
}
}
-static void spi_qup_fifo_write(struct spi_qup *controller,
+static void spi_qup_read(struct spi_qup *controller,
struct spi_transfer *xfer)
{
- const u8 *tx_buf = xfer->tx_buf;
- u32 word, state, data;
- int idx, w_size;
+ u32 remainder, words_per_block, num_words;
+ bool is_block_mode = controller->mode == QUP_IO_M_MODE_BLOCK;
+
+ remainder = DIV_ROUND_UP(xfer->len - controller->rx_bytes,
+ controller->w_size);
+ words_per_block = controller->in_blk_sz >> 2;
+
+ do {
+ /* ACK by clearing service flag */
+ writel_relaxed(QUP_OP_IN_SERVICE_FLAG,
+ controller->base + QUP_OPERATIONAL);
+
+ if (is_block_mode) {
+ num_words = (remainder > words_per_block) ?
+ words_per_block : remainder;
+ } else {
+ if (!spi_qup_is_flag_set(controller,
+ QUP_OP_IN_FIFO_NOT_EMPTY))
+ break;
- w_size = controller->w_size;
+ num_words = 1;
+ }
+
+ /* read up to the maximum transfer size available */
+ spi_qup_read_from_fifo(controller, xfer, num_words);
- while (controller->tx_bytes < xfer->len) {
+ remainder -= num_words;
- state = readl_relaxed(controller->base + QUP_OPERATIONAL);
- if (state & QUP_OP_OUT_FIFO_FULL)
+ /* if block mode, check to see if next block is available */
+ if (is_block_mode && !spi_qup_is_flag_set(controller,
+ QUP_OP_IN_BLOCK_READ_REQ))
break;
+ } while (remainder);
+
+ /*
+ * Due to extra stickiness of the QUP_OP_IN_SERVICE_FLAG during block
+ * mode reads, it has to be cleared again at the very end
+ */
+ if (is_block_mode && spi_qup_is_flag_set(controller,
+ QUP_OP_MAX_INPUT_DONE_FLAG))
+ writel_relaxed(QUP_OP_IN_SERVICE_FLAG,
+ controller->base + QUP_OPERATIONAL);
+
+}
+
+static void spi_qup_write_to_fifo(struct spi_qup *controller,
+ struct spi_transfer *xfer, u32 num_words)
+{
+ const u8 *tx_buf = xfer->tx_buf;
+ int i, num_bytes;
+ u32 word, data;
+
+ for (; num_words; num_words--) {
word = 0;
- for (idx = 0; idx < w_size; idx++, controller->tx_bytes++) {
- if (!tx_buf) {
- controller->tx_bytes += w_size;
- break;
+ num_bytes = min_t(int, xfer->len - controller->tx_bytes,
+ controller->w_size);
+ if (tx_buf)
+ for (i = 0; i < num_bytes; i++) {
+ data = tx_buf[controller->tx_bytes + i];
+ word |= data << (BITS_PER_BYTE * (3 - i));
}
- data = tx_buf[controller->tx_bytes];
- word |= data << (BITS_PER_BYTE * (3 - idx));
- }
+ controller->tx_bytes += num_bytes;
writel_relaxed(word, controller->base + QUP_OUTPUT_FIFO);
}
@@ -291,6 +338,44 @@ static void spi_qup_dma_done(void *data)
complete(done);
}
+static void spi_qup_write(struct spi_qup *controller,
+ struct spi_transfer *xfer)
+{
+ bool is_block_mode = controller->mode == QUP_IO_M_MODE_BLOCK;
+ u32 remainder, words_per_block, num_words;
+
+ remainder = DIV_ROUND_UP(xfer->len - controller->tx_bytes,
+ controller->w_size);
+ words_per_block = controller->out_blk_sz >> 2;
+
+ do {
+ /* ACK by clearing service flag */
+ writel_relaxed(QUP_OP_OUT_SERVICE_FLAG,
+ controller->base + QUP_OPERATIONAL);
+
+ if (is_block_mode) {
+ num_words = (remainder > words_per_block) ?
+ words_per_block : remainder;
+ } else {
+ if (spi_qup_is_flag_set(controller,
+ QUP_OP_OUT_FIFO_FULL))
+ break;
+
+ num_words = 1;
+ }
+
+ spi_qup_write_to_fifo(controller, xfer, num_words);
+
+ remainder -= num_words;
+
+ /* if block mode, check to see if next block is available */
+ if (is_block_mode && !spi_qup_is_flag_set(controller,
+ QUP_OP_OUT_BLOCK_WRITE_REQ))
+ break;
+
+ } while (remainder);
+}
+
static int spi_qup_prep_sg(struct spi_master *master, struct spi_transfer *xfer,
enum dma_transfer_direction dir,
dma_async_tx_callback callback,
@@ -348,11 +433,13 @@ unsigned long timeout)
return ret;
}
- if (xfer->rx_buf)
- rx_done = spi_qup_dma_done;
+ if (!qup->qup_v1) {
+ if (xfer->rx_buf)
+ rx_done = spi_qup_dma_done;
- if (xfer->tx_buf)
- tx_done = spi_qup_dma_done;
+ if (xfer->tx_buf)
+ tx_done = spi_qup_dma_done;
+ }
if (xfer->rx_buf) {
ret = spi_qup_prep_sg(master, xfer, DMA_DEV_TO_MEM, rx_done,
@@ -401,7 +488,7 @@ static int spi_qup_do_pio(struct spi_mas
}
if (qup->mode == QUP_IO_M_MODE_FIFO)
- spi_qup_fifo_write(qup, xfer);
+ spi_qup_write(qup, xfer);
ret = spi_qup_set_state(qup, QUP_STATE_RUN);
if (ret) {
@@ -434,10 +521,11 @@ static irqreturn_t spi_qup_qup_irq(int i
writel_relaxed(qup_err, controller->base + QUP_ERROR_FLAGS);
writel_relaxed(spi_err, controller->base + SPI_ERROR_FLAGS);
- writel_relaxed(opflags, controller->base + QUP_OPERATIONAL);
if (!xfer) {
- dev_err_ratelimited(controller->dev, "unexpected irq %08x %08x %08x\n",
+ writel_relaxed(opflags, controller->base + QUP_OPERATIONAL);
+ dev_err_ratelimited(controller->dev,
+ "unexpected irq %08x %08x %08x\n",
qup_err, spi_err, opflags);
return IRQ_HANDLED;
}
@@ -463,12 +551,20 @@ static irqreturn_t spi_qup_qup_irq(int i
error = -EIO;
}
- if (!spi_qup_is_dma_xfer(controller->mode)) {
+ if (spi_qup_is_dma_xfer(controller->mode)) {
+ writel_relaxed(opflags, controller->base + QUP_OPERATIONAL);
+ if (opflags & QUP_OP_IN_SERVICE_FLAG &&
+ opflags & QUP_OP_MAX_INPUT_DONE_FLAG)
+ complete(&controller->done);
+ if (opflags & QUP_OP_OUT_SERVICE_FLAG &&
+ opflags & QUP_OP_MAX_OUTPUT_DONE_FLAG)
+ complete(&controller->dma_tx_done);
+ } else {
if (opflags & QUP_OP_IN_SERVICE_FLAG)
- spi_qup_fifo_read(controller, xfer);
+ spi_qup_read(controller, xfer);
if (opflags & QUP_OP_OUT_SERVICE_FLAG)
- spi_qup_fifo_write(controller, xfer);
+ spi_qup_write(controller, xfer);
}
spin_lock_irqsave(&controller->lock, flags);
@@ -476,6 +572,9 @@ static irqreturn_t spi_qup_qup_irq(int i
controller->xfer = xfer;
spin_unlock_irqrestore(&controller->lock, flags);
+ /* re-read opflags as flags may have changed due to actions above */
+ opflags = readl_relaxed(controller->base + QUP_OPERATIONAL);
+
if ((controller->rx_bytes == xfer->len &&
(opflags & QUP_OP_MAX_INPUT_DONE_FLAG)) || error)
complete(&controller->done);
@@ -519,11 +618,13 @@ static int spi_qup_io_config(struct spi_
/* must be zero for FIFO */
writel_relaxed(0, controller->base + QUP_MX_INPUT_CNT);
writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT);
- controller->use_dma = 0;
} else if (spi->master->can_dma &&
spi->master->can_dma(spi->master, spi, xfer) &&
spi->master->cur_msg_mapped) {
controller->mode = QUP_IO_M_MODE_BAM;
+ writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT);
+ writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT);
+ /* must be zero for BLOCK and BAM */
writel_relaxed(0, controller->base + QUP_MX_READ_CNT);
writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT);