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-rw-r--r--drivers/spi/spi-imx.c625
1 files changed, 519 insertions, 106 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index b8b79bb7fec3..69c288c8c737 100644
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -60,6 +60,7 @@ MODULE_PARM_DESC(polling_limit_us,
#define MX51_ECSPI_CTRL_MAX_BURST 512
/* The maximum bytes that IMX53_ECSPI can transfer in target mode.*/
#define MX53_MAX_TRANSFER_BYTES 512
+#define BYTES_PER_32BITS_WORD 4
enum spi_imx_devtype {
IMX1_CSPI,
@@ -95,6 +96,16 @@ struct spi_imx_devtype_data {
enum spi_imx_devtype devtype;
};
+struct dma_data_package {
+ u32 cmd_word;
+ void *dma_rx_buf;
+ void *dma_tx_buf;
+ dma_addr_t dma_tx_addr;
+ dma_addr_t dma_rx_addr;
+ int dma_len;
+ int data_len;
+};
+
struct spi_imx_data {
struct spi_controller *controller;
struct device *dev;
@@ -130,6 +141,9 @@ struct spi_imx_data {
u32 wml;
struct completion dma_rx_completion;
struct completion dma_tx_completion;
+ size_t dma_package_num;
+ struct dma_data_package *dma_data;
+ int rx_offset;
const struct spi_imx_devtype_data *devtype_data;
};
@@ -189,6 +203,9 @@ MXC_SPI_BUF_TX(u16)
MXC_SPI_BUF_RX(u32)
MXC_SPI_BUF_TX(u32)
+/* Align to cache line to avoid swiotlo bounce */
+#define DMA_CACHE_ALIGNED_LEN(x) ALIGN((x), dma_get_cache_alignment())
+
/* First entry is reserved, second entry is valid only if SDHC_SPIEN is set
* (which is currently not the case in this driver)
*/
@@ -247,12 +264,26 @@ static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device
if (!controller->dma_rx)
return false;
- if (spi_imx->target_mode)
+ /*
+ * Due to Freescale errata ERR003775 "eCSPI: Burst completion by Chip
+ * Select (SS) signal in Slave mode is not functional" burst size must
+ * be set exactly to the size of the transfer. This limit SPI transaction
+ * with maximum 2^12 bits.
+ */
+ if (transfer->len > MX53_MAX_TRANSFER_BYTES && spi_imx->target_mode)
return false;
if (transfer->len < spi_imx->devtype_data->fifo_size)
return false;
+ /* DMA only can transmit data in bytes */
+ if (spi_imx->bits_per_word != 8 && spi_imx->bits_per_word != 16 &&
+ spi_imx->bits_per_word != 32)
+ return false;
+
+ if (transfer->len >= MAX_SDMA_BD_BYTES)
+ return false;
+
spi_imx->dynamic_burst = 0;
return true;
@@ -1282,50 +1313,6 @@ static irqreturn_t spi_imx_isr(int irq, void *dev_id)
return IRQ_HANDLED;
}
-static int spi_imx_dma_configure(struct spi_controller *controller)
-{
- int ret;
- enum dma_slave_buswidth buswidth;
- struct dma_slave_config rx = {}, tx = {};
- struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
-
- switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
- case 4:
- buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
- break;
- case 2:
- buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
- break;
- case 1:
- buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
- break;
- default:
- return -EINVAL;
- }
-
- tx.direction = DMA_MEM_TO_DEV;
- tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
- tx.dst_addr_width = buswidth;
- tx.dst_maxburst = spi_imx->wml;
- ret = dmaengine_slave_config(controller->dma_tx, &tx);
- if (ret) {
- dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
- return ret;
- }
-
- rx.direction = DMA_DEV_TO_MEM;
- rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
- rx.src_addr_width = buswidth;
- rx.src_maxburst = spi_imx->wml;
- ret = dmaengine_slave_config(controller->dma_rx, &rx);
- if (ret) {
- dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
- return ret;
- }
-
- return 0;
-}
-
static int spi_imx_setupxfer(struct spi_device *spi,
struct spi_transfer *t)
{
@@ -1442,8 +1429,6 @@ static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx,
init_completion(&spi_imx->dma_rx_completion);
init_completion(&spi_imx->dma_tx_completion);
- controller->can_dma = spi_imx_can_dma;
- controller->max_dma_len = MAX_SDMA_BD_BYTES;
spi_imx->controller->flags = SPI_CONTROLLER_MUST_RX |
SPI_CONTROLLER_MUST_TX;
@@ -1481,71 +1466,302 @@ static int spi_imx_calculate_timeout(struct spi_imx_data *spi_imx, int size)
return secs_to_jiffies(2 * timeout);
}
-static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
- struct spi_transfer *transfer)
+static void spi_imx_dma_unmap(struct spi_imx_data *spi_imx,
+ struct dma_data_package *dma_data)
+{
+ struct device *tx_dev = spi_imx->controller->dma_tx->device->dev;
+ struct device *rx_dev = spi_imx->controller->dma_rx->device->dev;
+
+ dma_unmap_single(tx_dev, dma_data->dma_tx_addr,
+ DMA_CACHE_ALIGNED_LEN(dma_data->dma_len),
+ DMA_TO_DEVICE);
+ dma_unmap_single(rx_dev, dma_data->dma_rx_addr,
+ DMA_CACHE_ALIGNED_LEN(dma_data->dma_len),
+ DMA_FROM_DEVICE);
+}
+
+static void spi_imx_dma_rx_data_handle(struct spi_imx_data *spi_imx,
+ struct dma_data_package *dma_data, void *rx_buf,
+ bool word_delay)
+{
+ void *copy_ptr;
+ int unaligned;
+
+ /*
+ * On little-endian CPUs, adjust byte order:
+ * - Swap bytes when bpw = 8
+ * - Swap half-words when bpw = 16
+ * This ensures correct data ordering for DMA transfers.
+ */
+#ifdef __LITTLE_ENDIAN
+ if (!word_delay) {
+ unsigned int bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
+ u32 *temp = dma_data->dma_rx_buf;
+
+ for (int i = 0; i < DIV_ROUND_UP(dma_data->dma_len, sizeof(*temp)); i++) {
+ if (bytes_per_word == 1)
+ swab32s(temp + i);
+ else if (bytes_per_word == 2)
+ swahw32s(temp + i);
+ }
+ }
+#endif
+
+ /*
+ * When dynamic burst enabled, DMA RX always receives 32-bit words from RXFIFO with
+ * buswidth = 4, but when data_len is not 4-bytes alignment, the RM shows when
+ * burst length = 32*n + m bits, a SPI burst contains the m LSB in first word and all
+ * 32 bits in other n words. So if garbage bytes in the first word, trim first word then
+ * copy the actual data to rx_buf.
+ */
+ if (dma_data->data_len % BYTES_PER_32BITS_WORD && !word_delay) {
+ unaligned = dma_data->data_len % BYTES_PER_32BITS_WORD;
+ copy_ptr = (u8 *)dma_data->dma_rx_buf + BYTES_PER_32BITS_WORD - unaligned;
+ } else {
+ copy_ptr = dma_data->dma_rx_buf;
+ }
+
+ memcpy(rx_buf, copy_ptr, dma_data->data_len);
+}
+
+static int spi_imx_dma_map(struct spi_imx_data *spi_imx,
+ struct dma_data_package *dma_data)
{
- struct dma_async_tx_descriptor *desc_tx, *desc_rx;
- unsigned long transfer_timeout;
- unsigned long time_left;
struct spi_controller *controller = spi_imx->controller;
- struct sg_table *tx = &transfer->tx_sg, *rx = &transfer->rx_sg;
- struct scatterlist *last_sg = sg_last(rx->sgl, rx->nents);
- unsigned int bytes_per_word, i;
+ struct device *tx_dev = controller->dma_tx->device->dev;
+ struct device *rx_dev = controller->dma_rx->device->dev;
int ret;
- /* Get the right burst length from the last sg to ensure no tail data */
- bytes_per_word = spi_imx_bytes_per_word(transfer->bits_per_word);
- for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
- if (!(sg_dma_len(last_sg) % (i * bytes_per_word)))
- break;
+ dma_data->dma_tx_addr = dma_map_single(tx_dev, dma_data->dma_tx_buf,
+ DMA_CACHE_ALIGNED_LEN(dma_data->dma_len),
+ DMA_TO_DEVICE);
+ ret = dma_mapping_error(tx_dev, dma_data->dma_tx_addr);
+ if (ret < 0) {
+ dev_err(spi_imx->dev, "DMA TX map failed %d\n", ret);
+ return ret;
}
- /* Use 1 as wml in case no available burst length got */
- if (i == 0)
- i = 1;
- spi_imx->wml = i;
+ dma_data->dma_rx_addr = dma_map_single(rx_dev, dma_data->dma_rx_buf,
+ DMA_CACHE_ALIGNED_LEN(dma_data->dma_len),
+ DMA_FROM_DEVICE);
+ ret = dma_mapping_error(rx_dev, dma_data->dma_rx_addr);
+ if (ret < 0) {
+ dev_err(spi_imx->dev, "DMA RX map failed %d\n", ret);
+ dma_unmap_single(tx_dev, dma_data->dma_tx_addr,
+ DMA_CACHE_ALIGNED_LEN(dma_data->dma_len),
+ DMA_TO_DEVICE);
+ return ret;
+ }
- ret = spi_imx_dma_configure(controller);
- if (ret)
- goto dma_failure_no_start;
+ return 0;
+}
- if (!spi_imx->devtype_data->setup_wml) {
- dev_err(spi_imx->dev, "No setup_wml()?\n");
- ret = -EINVAL;
- goto dma_failure_no_start;
+static int spi_imx_dma_tx_data_handle(struct spi_imx_data *spi_imx,
+ struct dma_data_package *dma_data,
+ const void *tx_buf,
+ bool word_delay)
+{
+ void *copy_ptr;
+ int unaligned;
+
+ if (word_delay) {
+ dma_data->dma_len = dma_data->data_len;
+ } else {
+ /*
+ * As per the reference manual, when burst length = 32*n + m bits, ECSPI
+ * sends m LSB bits in the first word, followed by n full 32-bit words.
+ * Since actual data may not be 4-byte aligned, allocate DMA TX/RX buffers
+ * to ensure alignment. For TX, DMA pushes 4-byte aligned words to TXFIFO,
+ * while ECSPI uses BURST_LENGTH settings to maintain correct bit count.
+ * For RX, DMA always receives 32-bit words from RXFIFO, when data len is
+ * not 4-byte aligned, trim the first word to drop garbage bytes, then group
+ * all transfer DMA bounse buffer and copy all valid data to rx_buf.
+ */
+ dma_data->dma_len = ALIGN(dma_data->data_len, BYTES_PER_32BITS_WORD);
}
- spi_imx->devtype_data->setup_wml(spi_imx);
+
+ dma_data->dma_tx_buf = kzalloc(dma_data->dma_len, GFP_KERNEL);
+ if (!dma_data->dma_tx_buf)
+ return -ENOMEM;
+
+ dma_data->dma_rx_buf = kzalloc(dma_data->dma_len, GFP_KERNEL);
+ if (!dma_data->dma_rx_buf) {
+ kfree(dma_data->dma_tx_buf);
+ return -ENOMEM;
+ }
+
+ if (dma_data->data_len % BYTES_PER_32BITS_WORD && !word_delay) {
+ unaligned = dma_data->data_len % BYTES_PER_32BITS_WORD;
+ copy_ptr = (u8 *)dma_data->dma_tx_buf + BYTES_PER_32BITS_WORD - unaligned;
+ } else {
+ copy_ptr = dma_data->dma_tx_buf;
+ }
+
+ memcpy(copy_ptr, tx_buf, dma_data->data_len);
+
+ /*
+ * When word_delay is enabled, DMA transfers an entire word in one minor loop.
+ * In this case, no data requires additional handling.
+ */
+ if (word_delay)
+ return 0;
+
+#ifdef __LITTLE_ENDIAN
+ /*
+ * On little-endian CPUs, adjust byte order:
+ * - Swap bytes when bpw = 8
+ * - Swap half-words when bpw = 16
+ * This ensures correct data ordering for DMA transfers.
+ */
+ unsigned int bytes_per_word = spi_imx_bytes_per_word(spi_imx->bits_per_word);
+ u32 *temp = dma_data->dma_tx_buf;
+
+ for (int i = 0; i < DIV_ROUND_UP(dma_data->dma_len, sizeof(*temp)); i++) {
+ if (bytes_per_word == 1)
+ swab32s(temp + i);
+ else if (bytes_per_word == 2)
+ swahw32s(temp + i);
+ }
+#endif
+
+ return 0;
+}
+
+static int spi_imx_dma_data_prepare(struct spi_imx_data *spi_imx,
+ struct spi_transfer *transfer,
+ bool word_delay)
+{
+ u32 pre_bl, tail_bl;
+ u32 ctrl;
+ int ret;
+
+ /*
+ * ECSPI supports a maximum burst of 512 bytes. When xfer->len exceeds 512
+ * and is not a multiple of 512, a tail transfer is required. BURST_LEGTH
+ * is used for SPI HW to maintain correct bit count. BURST_LENGTH should
+ * update with data length. After DMA request submit, SPI can not update the
+ * BURST_LENGTH, in this case, we must split two package, update the register
+ * then setup second DMA transfer.
+ */
+ ctrl = readl(spi_imx->base + MX51_ECSPI_CTRL);
+ if (word_delay) {
+ /*
+ * When SPI IMX need to support word delay, according to "Sample Period Control
+ * Register" shows, The Sample Period Control Register (ECSPI_PERIODREG)
+ * provides software a way to insert delays (wait states) between consecutive
+ * SPI transfers. As a result, ECSPI can only transfer one word per frame, and
+ * the delay occurs between frames.
+ */
+ spi_imx->dma_package_num = 1;
+ pre_bl = spi_imx->bits_per_word - 1;
+ } else if (transfer->len <= MX51_ECSPI_CTRL_MAX_BURST) {
+ spi_imx->dma_package_num = 1;
+ pre_bl = transfer->len * BITS_PER_BYTE - 1;
+ } else if (!(transfer->len % MX51_ECSPI_CTRL_MAX_BURST)) {
+ spi_imx->dma_package_num = 1;
+ pre_bl = MX51_ECSPI_CTRL_MAX_BURST * BITS_PER_BYTE - 1;
+ } else {
+ spi_imx->dma_package_num = 2;
+ pre_bl = MX51_ECSPI_CTRL_MAX_BURST * BITS_PER_BYTE - 1;
+ tail_bl = (transfer->len % MX51_ECSPI_CTRL_MAX_BURST) * BITS_PER_BYTE - 1;
+ }
+
+ spi_imx->dma_data = kmalloc_array(spi_imx->dma_package_num,
+ sizeof(struct dma_data_package),
+ GFP_KERNEL | __GFP_ZERO);
+ if (!spi_imx->dma_data) {
+ dev_err(spi_imx->dev, "Failed to allocate DMA package buffer!\n");
+ return -ENOMEM;
+ }
+
+ if (spi_imx->dma_package_num == 1) {
+ ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
+ ctrl |= pre_bl << MX51_ECSPI_CTRL_BL_OFFSET;
+ spi_imx->dma_data[0].cmd_word = ctrl;
+ spi_imx->dma_data[0].data_len = transfer->len;
+ ret = spi_imx_dma_tx_data_handle(spi_imx, &spi_imx->dma_data[0], transfer->tx_buf,
+ word_delay);
+ if (ret) {
+ kfree(spi_imx->dma_data);
+ return ret;
+ }
+ } else {
+ ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
+ ctrl |= pre_bl << MX51_ECSPI_CTRL_BL_OFFSET;
+ spi_imx->dma_data[0].cmd_word = ctrl;
+ spi_imx->dma_data[0].data_len = round_down(transfer->len,
+ MX51_ECSPI_CTRL_MAX_BURST);
+ ret = spi_imx_dma_tx_data_handle(spi_imx, &spi_imx->dma_data[0], transfer->tx_buf,
+ false);
+ if (ret) {
+ kfree(spi_imx->dma_data);
+ return ret;
+ }
+
+ ctrl &= ~MX51_ECSPI_CTRL_BL_MASK;
+ ctrl |= tail_bl << MX51_ECSPI_CTRL_BL_OFFSET;
+ spi_imx->dma_data[1].cmd_word = ctrl;
+ spi_imx->dma_data[1].data_len = transfer->len % MX51_ECSPI_CTRL_MAX_BURST;
+ ret = spi_imx_dma_tx_data_handle(spi_imx, &spi_imx->dma_data[1],
+ transfer->tx_buf + spi_imx->dma_data[0].data_len,
+ false);
+ if (ret) {
+ kfree(spi_imx->dma_data[0].dma_tx_buf);
+ kfree(spi_imx->dma_data[0].dma_rx_buf);
+ kfree(spi_imx->dma_data);
+ }
+ }
+
+ return 0;
+}
+
+static int spi_imx_dma_submit(struct spi_imx_data *spi_imx,
+ struct dma_data_package *dma_data,
+ struct spi_transfer *transfer)
+{
+ struct spi_controller *controller = spi_imx->controller;
+ struct dma_async_tx_descriptor *desc_tx, *desc_rx;
+ unsigned long transfer_timeout;
+ unsigned long time_left;
+ dma_cookie_t cookie;
/*
* The TX DMA setup starts the transfer, so make sure RX is configured
* before TX.
*/
- desc_rx = dmaengine_prep_slave_sg(controller->dma_rx,
- rx->sgl, rx->nents, DMA_DEV_TO_MEM,
- DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ desc_rx = dmaengine_prep_slave_single(controller->dma_rx, dma_data->dma_rx_addr,
+ dma_data->dma_len, DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_rx) {
- ret = -EINVAL;
- goto dma_failure_no_start;
+ transfer->error |= SPI_TRANS_FAIL_NO_START;
+ return -EINVAL;
}
desc_rx->callback = spi_imx_dma_rx_callback;
desc_rx->callback_param = (void *)spi_imx;
- dmaengine_submit(desc_rx);
+ cookie = dmaengine_submit(desc_rx);
+ if (dma_submit_error(cookie)) {
+ dev_err(spi_imx->dev, "submitting DMA RX failed\n");
+ transfer->error |= SPI_TRANS_FAIL_NO_START;
+ goto dmaengine_terminate_rx;
+ }
+
reinit_completion(&spi_imx->dma_rx_completion);
dma_async_issue_pending(controller->dma_rx);
- desc_tx = dmaengine_prep_slave_sg(controller->dma_tx,
- tx->sgl, tx->nents, DMA_MEM_TO_DEV,
- DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
- if (!desc_tx) {
- dmaengine_terminate_all(controller->dma_tx);
- dmaengine_terminate_all(controller->dma_rx);
- return -EINVAL;
- }
+ desc_tx = dmaengine_prep_slave_single(controller->dma_tx, dma_data->dma_tx_addr,
+ dma_data->dma_len, DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc_tx)
+ goto dmaengine_terminate_rx;
desc_tx->callback = spi_imx_dma_tx_callback;
desc_tx->callback_param = (void *)spi_imx;
- dmaengine_submit(desc_tx);
+ cookie = dmaengine_submit(desc_tx);
+ if (dma_submit_error(cookie)) {
+ dev_err(spi_imx->dev, "submitting DMA TX failed\n");
+ goto dmaengine_terminate_tx;
+ }
reinit_completion(&spi_imx->dma_tx_completion);
dma_async_issue_pending(controller->dma_tx);
@@ -1553,32 +1769,221 @@ static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
transfer_timeout = spi_imx_calculate_timeout(spi_imx, transfer->len);
- /* Wait SDMA to finish the data transfer.*/
- time_left = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
- transfer_timeout);
- if (!time_left) {
- dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
- dmaengine_terminate_all(controller->dma_tx);
- dmaengine_terminate_all(controller->dma_rx);
- return -ETIMEDOUT;
+ if (!spi_imx->target_mode) {
+ /* Wait SDMA to finish the data transfer.*/
+ time_left = wait_for_completion_timeout(&spi_imx->dma_tx_completion,
+ transfer_timeout);
+ if (!time_left) {
+ dev_err(spi_imx->dev, "I/O Error in DMA TX\n");
+ dmaengine_terminate_all(controller->dma_tx);
+ dmaengine_terminate_all(controller->dma_rx);
+ return -ETIMEDOUT;
+ }
+
+ time_left = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
+ transfer_timeout);
+ if (!time_left) {
+ dev_err(&controller->dev, "I/O Error in DMA RX\n");
+ spi_imx->devtype_data->reset(spi_imx);
+ dmaengine_terminate_all(controller->dma_rx);
+ return -ETIMEDOUT;
+ }
+ } else {
+ spi_imx->target_aborted = false;
+
+ if (wait_for_completion_interruptible(&spi_imx->dma_tx_completion) ||
+ READ_ONCE(spi_imx->target_aborted)) {
+ dev_dbg(spi_imx->dev, "I/O Error in DMA TX interrupted\n");
+ dmaengine_terminate_all(controller->dma_tx);
+ dmaengine_terminate_all(controller->dma_rx);
+ return -EINTR;
+ }
+
+ if (wait_for_completion_interruptible(&spi_imx->dma_rx_completion) ||
+ READ_ONCE(spi_imx->target_aborted)) {
+ dev_dbg(spi_imx->dev, "I/O Error in DMA RX interrupted\n");
+ dmaengine_terminate_all(controller->dma_rx);
+ return -EINTR;
+ }
+
+ /*
+ * ECSPI has a HW issue when works in Target mode, after 64 words
+ * writtern to TXFIFO, even TXFIFO becomes empty, ECSPI_TXDATA keeps
+ * shift out the last word data, so we have to disable ECSPI when in
+ * target mode after the transfer completes.
+ */
+ if (spi_imx->devtype_data->disable)
+ spi_imx->devtype_data->disable(spi_imx);
}
- time_left = wait_for_completion_timeout(&spi_imx->dma_rx_completion,
- transfer_timeout);
- if (!time_left) {
- dev_err(&controller->dev, "I/O Error in DMA RX\n");
- spi_imx->devtype_data->reset(spi_imx);
- dmaengine_terminate_all(controller->dma_rx);
- return -ETIMEDOUT;
+ return 0;
+
+dmaengine_terminate_tx:
+ dmaengine_terminate_all(controller->dma_tx);
+dmaengine_terminate_rx:
+ dmaengine_terminate_all(controller->dma_rx);
+
+ return -EINVAL;
+}
+
+static void spi_imx_dma_max_wml_find(struct spi_imx_data *spi_imx,
+ struct dma_data_package *dma_data,
+ bool word_delay)
+{
+ unsigned int bytes_per_word = word_delay ?
+ spi_imx_bytes_per_word(spi_imx->bits_per_word) :
+ BYTES_PER_32BITS_WORD;
+ unsigned int i;
+
+ for (i = spi_imx->devtype_data->fifo_size / 2; i > 0; i--) {
+ if (!dma_data->dma_len % (i * bytes_per_word))
+ break;
+ }
+ /* Use 1 as wml in case no available burst length got */
+ if (i == 0)
+ i = 1;
+
+ spi_imx->wml = i;
+}
+
+static int spi_imx_dma_configure(struct spi_controller *controller, bool word_delay)
+{
+ int ret;
+ enum dma_slave_buswidth buswidth;
+ struct dma_slave_config rx = {}, tx = {};
+ struct spi_imx_data *spi_imx = spi_controller_get_devdata(controller);
+
+ if (word_delay) {
+ switch (spi_imx_bytes_per_word(spi_imx->bits_per_word)) {
+ case 4:
+ buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ break;
+ case 2:
+ buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ break;
+ case 1:
+ buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ break;
+ default:
+ return -EINVAL;
+ }
+ } else {
+ buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ }
+
+ tx.direction = DMA_MEM_TO_DEV;
+ tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA;
+ tx.dst_addr_width = buswidth;
+ tx.dst_maxburst = spi_imx->wml;
+ ret = dmaengine_slave_config(controller->dma_tx, &tx);
+ if (ret) {
+ dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret);
+ return ret;
+ }
+
+ rx.direction = DMA_DEV_TO_MEM;
+ rx.src_addr = spi_imx->base_phys + MXC_CSPIRXDATA;
+ rx.src_addr_width = buswidth;
+ rx.src_maxburst = spi_imx->wml;
+ ret = dmaengine_slave_config(controller->dma_rx, &rx);
+ if (ret) {
+ dev_err(spi_imx->dev, "RX dma configuration failed with %d\n", ret);
+ return ret;
}
return 0;
+}
+
+static int spi_imx_dma_package_transfer(struct spi_imx_data *spi_imx,
+ struct dma_data_package *dma_data,
+ struct spi_transfer *transfer,
+ bool word_delay)
+{
+ struct spi_controller *controller = spi_imx->controller;
+ int ret;
+
+ spi_imx_dma_max_wml_find(spi_imx, dma_data, word_delay);
+
+ ret = spi_imx_dma_configure(controller, word_delay);
+ if (ret)
+ goto dma_failure_no_start;
+
+ if (!spi_imx->devtype_data->setup_wml) {
+ dev_err(spi_imx->dev, "No setup_wml()?\n");
+ ret = -EINVAL;
+ goto dma_failure_no_start;
+ }
+ spi_imx->devtype_data->setup_wml(spi_imx);
+
+ ret = spi_imx_dma_submit(spi_imx, dma_data, transfer);
+ if (ret)
+ return ret;
+
+ /* Trim the DMA RX buffer and copy the actual data to rx_buf */
+ dma_sync_single_for_cpu(controller->dma_rx->device->dev, dma_data->dma_rx_addr,
+ dma_data->dma_len, DMA_FROM_DEVICE);
+ spi_imx_dma_rx_data_handle(spi_imx, dma_data, transfer->rx_buf + spi_imx->rx_offset,
+ word_delay);
+ spi_imx->rx_offset += dma_data->data_len;
+
+ return 0;
/* fallback to pio */
dma_failure_no_start:
transfer->error |= SPI_TRANS_FAIL_NO_START;
return ret;
}
+static int spi_imx_dma_transfer(struct spi_imx_data *spi_imx,
+ struct spi_transfer *transfer)
+{
+ bool word_delay = transfer->word_delay.value != 0 && !spi_imx->target_mode;
+ int ret;
+ int i;
+
+ ret = spi_imx_dma_data_prepare(spi_imx, transfer, word_delay);
+ if (ret < 0) {
+ transfer->error |= SPI_TRANS_FAIL_NO_START;
+ dev_err(spi_imx->dev, "DMA data prepare fail\n");
+ goto fallback_pio;
+ }
+
+ spi_imx->rx_offset = 0;
+
+ /* Each dma_package performs a separate DMA transfer once */
+ for (i = 0; i < spi_imx->dma_package_num; i++) {
+ ret = spi_imx_dma_map(spi_imx, &spi_imx->dma_data[i]);
+ if (ret < 0) {
+ if (i == 0)
+ transfer->error |= SPI_TRANS_FAIL_NO_START;
+ dev_err(spi_imx->dev, "DMA map fail\n");
+ break;
+ }
+
+ /* Update the CTRL register BL field */
+ writel(spi_imx->dma_data[i].cmd_word, spi_imx->base + MX51_ECSPI_CTRL);
+
+ ret = spi_imx_dma_package_transfer(spi_imx, &spi_imx->dma_data[i],
+ transfer, word_delay);
+
+ /* Whether the dma transmission is successful or not, dma unmap is necessary */
+ spi_imx_dma_unmap(spi_imx, &spi_imx->dma_data[i]);
+
+ if (ret < 0) {
+ dev_dbg(spi_imx->dev, "DMA %d transfer not really finish\n", i);
+ break;
+ }
+ }
+
+ for (int j = 0; j < spi_imx->dma_package_num; j++) {
+ kfree(spi_imx->dma_data[j].dma_tx_buf);
+ kfree(spi_imx->dma_data[j].dma_rx_buf);
+ }
+ kfree(spi_imx->dma_data);
+
+fallback_pio:
+ return ret;
+}
+
static int spi_imx_pio_transfer(struct spi_device *spi,
struct spi_transfer *transfer)
{
@@ -1737,7 +2142,7 @@ static int spi_imx_transfer_one(struct spi_controller *controller,
while (spi_imx->devtype_data->rx_available(spi_imx))
readl(spi_imx->base + MXC_CSPIRXDATA);
- if (spi_imx->target_mode)
+ if (spi_imx->target_mode && !spi_imx->usedma)
return spi_imx_pio_transfer_target(spi, transfer);
/*
@@ -1745,9 +2150,17 @@ static int spi_imx_transfer_one(struct spi_controller *controller,
* transfer, the SPI transfer has already been mapped, so we
* have to do the DMA transfer here.
*/
- if (spi_imx->usedma)
- return spi_imx_dma_transfer(spi_imx, transfer);
-
+ if (spi_imx->usedma) {
+ ret = spi_imx_dma_transfer(spi_imx, transfer);
+ if (transfer->error & SPI_TRANS_FAIL_NO_START) {
+ spi_imx->usedma = false;
+ if (spi_imx->target_mode)
+ return spi_imx_pio_transfer_target(spi, transfer);
+ else
+ return spi_imx_pio_transfer(spi, transfer);
+ }
+ return ret;
+ }
/* run in polling mode for short transfers */
if (transfer->len == 1 || (polling_limit_us &&
spi_imx_transfer_estimate_time_us(transfer) < polling_limit_us))