diff options
Diffstat (limited to 'drivers/spi/spi-stm32-qspi.c')
| -rw-r--r-- | drivers/spi/spi-stm32-qspi.c | 136 |
1 files changed, 135 insertions, 1 deletions
diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c index 9875139ef0cf..11a89aa15d56 100644 --- a/drivers/spi/spi-stm32-qspi.c +++ b/drivers/spi/spi-stm32-qspi.c @@ -5,6 +5,8 @@ */ #include <linux/bitfield.h> #include <linux/clk.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> #include <linux/errno.h> #include <linux/io.h> #include <linux/iopoll.h> @@ -84,6 +86,7 @@ #define STM32_FIFO_TIMEOUT_US 30000 #define STM32_BUSY_TIMEOUT_US 100000 #define STM32_ABT_TIMEOUT_US 100000 +#define STM32_COMP_TIMEOUT_MS 1000 struct stm32_qspi_flash { struct stm32_qspi *qspi; @@ -94,6 +97,7 @@ struct stm32_qspi_flash { struct stm32_qspi { struct device *dev; struct spi_controller *ctrl; + phys_addr_t phys_base; void __iomem *io_base; void __iomem *mm_base; resource_size_t mm_size; @@ -103,6 +107,10 @@ struct stm32_qspi { struct completion data_completion; u32 fmode; + struct dma_chan *dma_chtx; + struct dma_chan *dma_chrx; + struct completion dma_completion; + u32 cr_reg; u32 dcr_reg; @@ -181,6 +189,81 @@ static int stm32_qspi_tx_mm(struct stm32_qspi *qspi, return 0; } +static void stm32_qspi_dma_callback(void *arg) +{ + struct completion *dma_completion = arg; + + complete(dma_completion); +} + +static int stm32_qspi_tx_dma(struct stm32_qspi *qspi, + const struct spi_mem_op *op) +{ + struct dma_async_tx_descriptor *desc; + enum dma_transfer_direction dma_dir; + struct dma_chan *dma_ch; + struct sg_table sgt; + dma_cookie_t cookie; + u32 cr, t_out; + int err; + + if (op->data.dir == SPI_MEM_DATA_IN) { + dma_dir = DMA_DEV_TO_MEM; + dma_ch = qspi->dma_chrx; + } else { + dma_dir = DMA_MEM_TO_DEV; + dma_ch = qspi->dma_chtx; + } + + /* + * spi_map_buf return -EINVAL if the buffer is not DMA-able + * (DMA-able: in vmalloc | kmap | virt_addr_valid) + */ + err = spi_controller_dma_map_mem_op_data(qspi->ctrl, op, &sgt); + if (err) + return err; + + desc = dmaengine_prep_slave_sg(dma_ch, sgt.sgl, sgt.nents, + dma_dir, DMA_PREP_INTERRUPT); + if (!desc) { + err = -ENOMEM; + goto out_unmap; + } + + cr = readl_relaxed(qspi->io_base + QSPI_CR); + + reinit_completion(&qspi->dma_completion); + desc->callback = stm32_qspi_dma_callback; + desc->callback_param = &qspi->dma_completion; + cookie = dmaengine_submit(desc); + err = dma_submit_error(cookie); + if (err) + goto out; + + dma_async_issue_pending(dma_ch); + + writel_relaxed(cr | CR_DMAEN, qspi->io_base + QSPI_CR); + + t_out = sgt.nents * STM32_COMP_TIMEOUT_MS; + if (!wait_for_completion_interruptible_timeout(&qspi->dma_completion, + msecs_to_jiffies(t_out))) + err = -ETIMEDOUT; + + if (dma_async_is_tx_complete(dma_ch, cookie, + NULL, NULL) != DMA_COMPLETE) + err = -ETIMEDOUT; + + if (err) + dmaengine_terminate_all(dma_ch); + +out: + writel_relaxed(cr & ~CR_DMAEN, qspi->io_base + QSPI_CR); +out_unmap: + spi_controller_dma_unmap_mem_op_data(qspi->ctrl, op, &sgt); + + return err; +} + static int stm32_qspi_tx(struct stm32_qspi *qspi, const struct spi_mem_op *op) { if (!op->data.nbytes) @@ -188,6 +271,10 @@ static int stm32_qspi_tx(struct stm32_qspi *qspi, const struct spi_mem_op *op) if (qspi->fmode == CCR_FMODE_MM) return stm32_qspi_tx_mm(qspi, op); + else if ((op->data.dir == SPI_MEM_DATA_IN && qspi->dma_chrx) || + (op->data.dir == SPI_MEM_DATA_OUT && qspi->dma_chtx)) + if (!stm32_qspi_tx_dma(qspi, op)) + return 0; return stm32_qspi_tx_poll(qspi, op); } @@ -218,7 +305,7 @@ static int stm32_qspi_wait_cmd(struct stm32_qspi *qspi, writel_relaxed(cr | CR_TCIE | CR_TEIE, qspi->io_base + QSPI_CR); if (!wait_for_completion_interruptible_timeout(&qspi->data_completion, - msecs_to_jiffies(1000))) { + msecs_to_jiffies(STM32_COMP_TIMEOUT_MS))) { err = -ETIMEDOUT; } else { sr = readl_relaxed(qspi->io_base + QSPI_SR); @@ -387,6 +474,49 @@ static int stm32_qspi_setup(struct spi_device *spi) return 0; } +static void stm32_qspi_dma_setup(struct stm32_qspi *qspi) +{ + struct dma_slave_config dma_cfg; + struct device *dev = qspi->dev; + + memset(&dma_cfg, 0, sizeof(dma_cfg)); + + dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; + dma_cfg.src_addr = qspi->phys_base + QSPI_DR; + dma_cfg.dst_addr = qspi->phys_base + QSPI_DR; + dma_cfg.src_maxburst = 4; + dma_cfg.dst_maxburst = 4; + + qspi->dma_chrx = dma_request_slave_channel(dev, "rx"); + if (qspi->dma_chrx) { + if (dmaengine_slave_config(qspi->dma_chrx, &dma_cfg)) { + dev_err(dev, "dma rx config failed\n"); + dma_release_channel(qspi->dma_chrx); + qspi->dma_chrx = NULL; + } + } + + qspi->dma_chtx = dma_request_slave_channel(dev, "tx"); + if (qspi->dma_chtx) { + if (dmaengine_slave_config(qspi->dma_chtx, &dma_cfg)) { + dev_err(dev, "dma tx config failed\n"); + dma_release_channel(qspi->dma_chtx); + qspi->dma_chtx = NULL; + } + } + + init_completion(&qspi->dma_completion); +} + +static void stm32_qspi_dma_free(struct stm32_qspi *qspi) +{ + if (qspi->dma_chtx) + dma_release_channel(qspi->dma_chtx); + if (qspi->dma_chrx) + dma_release_channel(qspi->dma_chrx); +} + /* * no special host constraint, so use default spi_mem_default_supports_op * to check supported mode. @@ -399,6 +529,7 @@ static void stm32_qspi_release(struct stm32_qspi *qspi) { /* disable qspi */ writel_relaxed(0, qspi->io_base + QSPI_CR); + stm32_qspi_dma_free(qspi); mutex_destroy(&qspi->lock); clk_disable_unprepare(qspi->clk); spi_master_put(qspi->ctrl); @@ -427,6 +558,8 @@ static int stm32_qspi_probe(struct platform_device *pdev) goto err; } + qspi->phys_base = res->start; + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mm"); qspi->mm_base = devm_ioremap_resource(dev, res); if (IS_ERR(qspi->mm_base)) { @@ -477,6 +610,7 @@ static int stm32_qspi_probe(struct platform_device *pdev) qspi->dev = dev; platform_set_drvdata(pdev, qspi); + stm32_qspi_dma_setup(qspi); mutex_init(&qspi->lock); ctrl->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD |