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author | Patrice Chotard <patrice.chotard@foss.st.com> | 2021-05-18 18:27:54 +0200 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2021-06-03 14:04:58 +0100 |
commit | 86d1c6bbae32122c5f703b2d8acccf5d4258f2bb (patch) | |
tree | bb25857b3c8f62cf4681893e610797524883ffb0 /drivers/spi | |
parent | 8941cd8d295e40f8ea1c0a5045d6d068b8e33eec (diff) | |
download | linux-86d1c6bbae32122c5f703b2d8acccf5d4258f2bb.tar.gz linux-86d1c6bbae32122c5f703b2d8acccf5d4258f2bb.tar.bz2 linux-86d1c6bbae32122c5f703b2d8acccf5d4258f2bb.zip |
spi: stm32-qspi: add automatic poll status feature
STM32 QSPI is able to automatically poll a specified register inside the
memory and relieve the CPU from this task.
As example, when erasing a large memory area, we got cpu load
equal to 50%. This patch allows to perform the same operation
with a cpu load around 2%.
Signed-off-by: Christophe Kerello <christophe.kerello@foss.st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
Link: https://lore.kernel.org/r/20210518162754.15940-4-patrice.chotard@foss.st.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-stm32-qspi.c | 86 |
1 files changed, 78 insertions, 8 deletions
diff --git a/drivers/spi/spi-stm32-qspi.c b/drivers/spi/spi-stm32-qspi.c index 7e640ccc7e77..69fd220a2894 100644 --- a/drivers/spi/spi-stm32-qspi.c +++ b/drivers/spi/spi-stm32-qspi.c @@ -36,6 +36,7 @@ #define CR_FTIE BIT(18) #define CR_SMIE BIT(19) #define CR_TOIE BIT(20) +#define CR_APMS BIT(22) #define CR_PRESC_MASK GENMASK(31, 24) #define QSPI_DCR 0x04 @@ -53,6 +54,7 @@ #define QSPI_FCR 0x0c #define FCR_CTEF BIT(0) #define FCR_CTCF BIT(1) +#define FCR_CSMF BIT(3) #define QSPI_DLR 0x10 @@ -107,6 +109,7 @@ struct stm32_qspi { u32 clk_rate; struct stm32_qspi_flash flash[STM32_QSPI_MAX_NORCHIP]; struct completion data_completion; + struct completion match_completion; u32 fmode; struct dma_chan *dma_chtx; @@ -115,6 +118,7 @@ struct stm32_qspi { u32 cr_reg; u32 dcr_reg; + unsigned long status_timeout; /* * to protect device configuration, could be different between @@ -128,11 +132,20 @@ static irqreturn_t stm32_qspi_irq(int irq, void *dev_id) struct stm32_qspi *qspi = (struct stm32_qspi *)dev_id; u32 cr, sr; + cr = readl_relaxed(qspi->io_base + QSPI_CR); sr = readl_relaxed(qspi->io_base + QSPI_SR); + if (cr & CR_SMIE && sr & SR_SMF) { + /* disable irq */ + cr &= ~CR_SMIE; + writel_relaxed(cr, qspi->io_base + QSPI_CR); + complete(&qspi->match_completion); + + return IRQ_HANDLED; + } + if (sr & (SR_TEF | SR_TCF)) { /* disable irq */ - cr = readl_relaxed(qspi->io_base + QSPI_CR); cr &= ~CR_TCIE & ~CR_TEIE; writel_relaxed(cr, qspi->io_base + QSPI_CR); complete(&qspi->data_completion); @@ -319,6 +332,24 @@ out: return err; } +static int stm32_qspi_wait_poll_status(struct stm32_qspi *qspi, + const struct spi_mem_op *op) +{ + u32 cr; + + reinit_completion(&qspi->match_completion); + cr = readl_relaxed(qspi->io_base + QSPI_CR); + writel_relaxed(cr | CR_SMIE, qspi->io_base + QSPI_CR); + + if (!wait_for_completion_timeout(&qspi->match_completion, + msecs_to_jiffies(qspi->status_timeout))) + return -ETIMEDOUT; + + writel_relaxed(FCR_CSMF, qspi->io_base + QSPI_FCR); + + return 0; +} + static int stm32_qspi_get_mode(struct stm32_qspi *qspi, u8 buswidth) { if (buswidth == 4) @@ -332,7 +363,7 @@ static int stm32_qspi_send(struct spi_mem *mem, const struct spi_mem_op *op) struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master); struct stm32_qspi_flash *flash = &qspi->flash[mem->spi->chip_select]; u32 ccr, cr; - int timeout, err = 0; + int timeout, err = 0, err_poll_status = 0; dev_dbg(qspi->dev, "cmd:%#x mode:%d.%d.%d.%d addr:%#llx len:%#x\n", op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth, @@ -378,6 +409,9 @@ static int stm32_qspi_send(struct spi_mem *mem, const struct spi_mem_op *op) if (op->addr.nbytes && qspi->fmode != CCR_FMODE_MM) writel_relaxed(op->addr.val, qspi->io_base + QSPI_AR); + if (qspi->fmode == CCR_FMODE_APM) + err_poll_status = stm32_qspi_wait_poll_status(qspi, op); + err = stm32_qspi_tx(qspi, op); /* @@ -387,7 +421,7 @@ static int stm32_qspi_send(struct spi_mem *mem, const struct spi_mem_op *op) * byte of device (device size - fifo size). like device size is not * knows, the prefetching is always stop. */ - if (err || qspi->fmode == CCR_FMODE_MM) + if (err || err_poll_status || qspi->fmode == CCR_FMODE_MM) goto abort; /* wait end of tx in indirect mode */ @@ -406,15 +440,49 @@ abort: cr, !(cr & CR_ABORT), 1, STM32_ABT_TIMEOUT_US); - writel_relaxed(FCR_CTCF, qspi->io_base + QSPI_FCR); + writel_relaxed(FCR_CTCF | FCR_CSMF, qspi->io_base + QSPI_FCR); - if (err || timeout) - dev_err(qspi->dev, "%s err:%d abort timeout:%d\n", - __func__, err, timeout); + if (err || err_poll_status || timeout) + dev_err(qspi->dev, "%s err:%d err_poll_status:%d abort timeout:%d\n", + __func__, err, err_poll_status, timeout); return err; } +static int stm32_qspi_poll_status(struct spi_mem *mem, const struct spi_mem_op *op, + u16 mask, u16 match, + unsigned long initial_delay_us, + unsigned long polling_rate_us, + unsigned long timeout_ms) +{ + struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master); + int ret; + + if (!spi_mem_supports_op(mem, op)) + return -EOPNOTSUPP; + + ret = pm_runtime_get_sync(qspi->dev); + if (ret < 0) { + pm_runtime_put_noidle(qspi->dev); + return ret; + } + + mutex_lock(&qspi->lock); + + writel_relaxed(mask, qspi->io_base + QSPI_PSMKR); + writel_relaxed(match, qspi->io_base + QSPI_PSMAR); + qspi->fmode = CCR_FMODE_APM; + qspi->status_timeout = timeout_ms; + + ret = stm32_qspi_send(mem, op); + mutex_unlock(&qspi->lock); + + pm_runtime_mark_last_busy(qspi->dev); + pm_runtime_put_autosuspend(qspi->dev); + + return ret; +} + static int stm32_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) { struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master); @@ -527,7 +595,7 @@ static int stm32_qspi_setup(struct spi_device *spi) flash->presc = presc; mutex_lock(&qspi->lock); - qspi->cr_reg = 3 << CR_FTHRES_SHIFT | CR_SSHIFT | CR_EN; + qspi->cr_reg = CR_APMS | 3 << CR_FTHRES_SHIFT | CR_SSHIFT | CR_EN; writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR); /* set dcr fsize to max address */ @@ -607,6 +675,7 @@ static const struct spi_controller_mem_ops stm32_qspi_mem_ops = { .exec_op = stm32_qspi_exec_op, .dirmap_create = stm32_qspi_dirmap_create, .dirmap_read = stm32_qspi_dirmap_read, + .poll_status = stm32_qspi_poll_status, }; static int stm32_qspi_probe(struct platform_device *pdev) @@ -661,6 +730,7 @@ static int stm32_qspi_probe(struct platform_device *pdev) } init_completion(&qspi->data_completion); + init_completion(&qspi->match_completion); qspi->clk = devm_clk_get(dev, NULL); if (IS_ERR(qspi->clk)) { |