diff options
author | Varadarajan Narayanan <varada@codeaurora.org> | 2017-07-28 09:52:57 +0300 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2017-08-08 14:15:39 +0300 |
commit | 5dc47fefe1d470da47dd400796bbf93ffe82fd33 (patch) | |
tree | 0451d79b6290e4d9afdd453254488851b5846ecb /drivers/spi | |
parent | 3b5ea2c981dd470882bdc83e548dd15a942dbf4d (diff) | |
download | linux-5dc47fefe1d470da47dd400796bbf93ffe82fd33.tar.xz |
spi: qup: allow block mode to generate multiple transactions
This let's you write more to the SPI bus than 64K-1 which is important
if the block size of a SPI device is >= 64K or some other device wants
to do something larger.
This has the benefit of completely removing spi_message from the spi-qup
transactions
Signed-off-by: Matthew McClintock <mmcclint@codeaurora.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 | 128 |
1 files changed, 80 insertions, 48 deletions
diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c index 1aa60785bf98..707b1ec427fa 100644 --- a/drivers/spi/spi-qup.c +++ b/drivers/spi/spi-qup.c @@ -120,7 +120,7 @@ #define SPI_NUM_CHIPSELECTS 4 -#define SPI_MAX_DMA_XFER (SZ_64K - 64) +#define SPI_MAX_XFER (SZ_64K - 64) /* high speed mode is when bus rate is greater then 26MHz */ #define SPI_HS_MIN_RATE 26000000 @@ -149,6 +149,8 @@ struct spi_qup { int n_words; int tx_bytes; int rx_bytes; + const u8 *tx_buf; + u8 *rx_buf; int qup_v1; int mode; @@ -173,6 +175,12 @@ static inline bool spi_qup_is_dma_xfer(int mode) return false; } +/* get's the transaction size length */ +static inline unsigned int spi_qup_len(struct spi_qup *controller) +{ + return controller->n_words * controller->w_size; +} + static inline bool spi_qup_is_valid_state(struct spi_qup *controller) { u32 opstate = readl_relaxed(controller->base + QUP_STATE); @@ -225,10 +233,9 @@ static int spi_qup_set_state(struct spi_qup *controller, u32 state) return 0; } -static void spi_qup_read_from_fifo(struct spi_qup *controller, - struct spi_transfer *xfer, u32 num_words) +static void spi_qup_read_from_fifo(struct spi_qup *controller, u32 num_words) { - u8 *rx_buf = xfer->rx_buf; + u8 *rx_buf = controller->rx_buf; int i, shift, num_bytes; u32 word; @@ -236,8 +243,9 @@ static void spi_qup_read_from_fifo(struct spi_qup *controller, word = readl_relaxed(controller->base + QUP_INPUT_FIFO); - num_bytes = min_t(int, xfer->len - controller->rx_bytes, - controller->w_size); + num_bytes = min_t(int, spi_qup_len(controller) - + controller->rx_bytes, + controller->w_size); if (!rx_buf) { controller->rx_bytes += num_bytes; @@ -258,13 +266,12 @@ static void spi_qup_read_from_fifo(struct spi_qup *controller, } } -static void spi_qup_read(struct spi_qup *controller, - struct spi_transfer *xfer) +static void spi_qup_read(struct spi_qup *controller) { 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, + remainder = DIV_ROUND_UP(spi_qup_len(controller) - controller->rx_bytes, controller->w_size); words_per_block = controller->in_blk_sz >> 2; @@ -285,7 +292,7 @@ static void spi_qup_read(struct spi_qup *controller, } /* read up to the maximum transfer size available */ - spi_qup_read_from_fifo(controller, xfer, num_words); + spi_qup_read_from_fifo(controller, num_words); remainder -= num_words; @@ -307,18 +314,18 @@ static void spi_qup_read(struct spi_qup *controller, } -static void spi_qup_write_to_fifo(struct spi_qup *controller, - struct spi_transfer *xfer, u32 num_words) +static void spi_qup_write_to_fifo(struct spi_qup *controller, u32 num_words) { - const u8 *tx_buf = xfer->tx_buf; + const u8 *tx_buf = controller->tx_buf; int i, num_bytes; u32 word, data; for (; num_words; num_words--) { word = 0; - num_bytes = min_t(int, xfer->len - controller->tx_bytes, - controller->w_size); + num_bytes = min_t(int, spi_qup_len(controller) - + controller->tx_bytes, + controller->w_size); if (tx_buf) for (i = 0; i < num_bytes; i++) { data = tx_buf[controller->tx_bytes + i]; @@ -338,13 +345,12 @@ static void spi_qup_dma_done(void *data) complete(&qup->done); } -static void spi_qup_write(struct spi_qup *controller, - struct spi_transfer *xfer) +static void spi_qup_write(struct spi_qup *controller) { 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, + remainder = DIV_ROUND_UP(spi_qup_len(controller) - controller->tx_bytes, controller->w_size); words_per_block = controller->out_blk_sz >> 2; @@ -364,7 +370,7 @@ static void spi_qup_write(struct spi_qup *controller, num_words = 1; } - spi_qup_write_to_fifo(controller, xfer, num_words); + spi_qup_write_to_fifo(controller, num_words); remainder -= num_words; @@ -471,36 +477,62 @@ static int spi_qup_do_pio(struct spi_device *spi, struct spi_transfer *xfer, { struct spi_master *master = spi->master; struct spi_qup *qup = spi_master_get_devdata(master); - int ret; + int ret, n_words, iterations, offset = 0; - ret = spi_qup_io_config(spi, xfer); - if (ret) - return ret; + n_words = qup->n_words; + iterations = n_words / SPI_MAX_XFER; /* round down */ + qup->rx_buf = xfer->rx_buf; + qup->tx_buf = xfer->tx_buf; - ret = spi_qup_set_state(qup, QUP_STATE_RUN); - if (ret) { - dev_warn(qup->dev, "cannot set RUN state\n"); - return ret; - } + do { + if (iterations) + qup->n_words = SPI_MAX_XFER; + else + qup->n_words = n_words % SPI_MAX_XFER; - ret = spi_qup_set_state(qup, QUP_STATE_PAUSE); - if (ret) { - dev_warn(qup->dev, "cannot set PAUSE state\n"); - return ret; - } + if (qup->tx_buf && offset) + qup->tx_buf = xfer->tx_buf + offset * SPI_MAX_XFER; - if (qup->mode == QUP_IO_M_MODE_FIFO) - spi_qup_write(qup, xfer); + if (qup->rx_buf && offset) + qup->rx_buf = xfer->rx_buf + offset * SPI_MAX_XFER; - ret = spi_qup_set_state(qup, QUP_STATE_RUN); - if (ret) { - dev_warn(qup->dev, "%s(%d): cannot set RUN state\n", - __func__, __LINE__); - return ret; - } + /* + * if the transaction is small enough, we need + * to fallback to FIFO mode + */ + if (qup->n_words <= (qup->in_fifo_sz / sizeof(u32))) + qup->mode = QUP_IO_M_MODE_FIFO; - if (!wait_for_completion_timeout(&qup->done, timeout)) - return -ETIMEDOUT; + ret = spi_qup_io_config(spi, xfer); + if (ret) + return ret; + + ret = spi_qup_set_state(qup, QUP_STATE_RUN); + if (ret) { + dev_warn(qup->dev, "cannot set RUN state\n"); + return ret; + } + + ret = spi_qup_set_state(qup, QUP_STATE_PAUSE); + if (ret) { + dev_warn(qup->dev, "cannot set PAUSE state\n"); + return ret; + } + + if (qup->mode == QUP_IO_M_MODE_FIFO) + spi_qup_write(qup); + + ret = spi_qup_set_state(qup, QUP_STATE_RUN); + if (ret) { + dev_warn(qup->dev, "cannot set RUN state\n"); + return ret; + } + + if (!wait_for_completion_timeout(&qup->done, timeout)) + return -ETIMEDOUT; + + offset++; + } while (iterations--); return 0; } @@ -508,7 +540,6 @@ static int spi_qup_do_pio(struct spi_device *spi, struct spi_transfer *xfer, static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id) { struct spi_qup *controller = dev_id; - struct spi_transfer *xfer = controller->xfer; u32 opflags, qup_err, spi_err; int error = 0; @@ -545,10 +576,10 @@ 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_read(controller, xfer); + spi_qup_read(controller); if (opflags & QUP_OP_OUT_SERVICE_FLAG) - spi_qup_write(controller, xfer); + spi_qup_write(controller); } if ((opflags & QUP_OP_MAX_INPUT_DONE_FLAG) || error) @@ -755,7 +786,8 @@ static int spi_qup_transfer_one(struct spi_master *master, return ret; timeout = DIV_ROUND_UP(xfer->speed_hz, MSEC_PER_SEC); - timeout = DIV_ROUND_UP(xfer->len * 8, timeout); + timeout = DIV_ROUND_UP(min_t(unsigned long, SPI_MAX_XFER, + xfer->len) * 8, timeout); timeout = 100 * msecs_to_jiffies(timeout); reinit_completion(&controller->done); @@ -969,7 +1001,7 @@ static int spi_qup_probe(struct platform_device *pdev) master->dev.of_node = pdev->dev.of_node; master->auto_runtime_pm = true; master->dma_alignment = dma_get_cache_alignment(); - master->max_dma_len = SPI_MAX_DMA_XFER; + master->max_dma_len = SPI_MAX_XFER; platform_set_drvdata(pdev, master); |