diff options
author | Varadarajan Narayanan <varada@codeaurora.org> | 2017-07-28 09:52:54 +0300 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2017-08-08 14:15:27 +0300 |
commit | 7538726f9ddaa53b72d61116728cf2d189b05202 (patch) | |
tree | e2e11e1d1cff416876de9eabe505506db0fbd044 /drivers/spi | |
parent | ce7dfc71c1123a4bc7ddc628fc759ede0f58a2fe (diff) | |
download | linux-7538726f9ddaa53b72d61116728cf2d189b05202.tar.xz |
spi: qup: Do block sized read/write in block mode
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>
Signed-off-by: Varadarajan Narayanan <varada@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-qup.c | 151 |
1 files changed, 119 insertions, 32 deletions
diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c index a7c630c4788c..8cfa112bb142 100644 --- a/drivers/spi/spi-qup.c +++ b/drivers/spi/spi-qup.c @@ -82,6 +82,8 @@ #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) @@ -154,6 +156,13 @@ 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) != 0; +} + static inline bool spi_qup_is_dma_xfer(int mode) { if (mode == QUP_IO_M_MODE_DMOV || mode == QUP_IO_M_MODE_BAM) @@ -214,29 +223,26 @@ static int spi_qup_set_state(struct spi_qup *controller, u32 state) 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; + int i, shift, num_bytes; + u32 word; - w_size = controller->w_size; - - 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 @@ -244,38 +250,80 @@ static void spi_qup_fifo_read(struct spi_qup *controller, * 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; + } - while (controller->tx_bytes < xfer->len) { + /* read up to the maximum transfer size available */ + spi_qup_read_from_fifo(controller, xfer, num_words); - state = readl_relaxed(controller->base + QUP_OPERATIONAL); - if (state & QUP_OP_OUT_FIFO_FULL) + 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_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); } @@ -288,6 +336,44 @@ static void spi_qup_dma_done(void *data) complete(&qup->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) @@ -391,7 +477,8 @@ static int spi_qup_do_pio(struct spi_master *master, struct spi_transfer *xfer, return ret; } - spi_qup_fifo_write(qup, xfer); + if (qup->mode == QUP_IO_M_MODE_FIFO) + spi_qup_write(qup, xfer); ret = spi_qup_set_state(qup, QUP_STATE_RUN); if (ret) { @@ -446,10 +533,10 @@ static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id) writel_relaxed(opflags, controller->base + QUP_OPERATIONAL); } 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); } if ((opflags & QUP_OP_MAX_INPUT_DONE_FLAG) || error) |