From 625de1881b5aee6a42a3130004e47dbd632429f8 Mon Sep 17 00:00:00 2001 From: Alexander Dahl Date: Wed, 18 Sep 2024 10:27:44 +0200 Subject: [PATCH] spi: atmel-quadspi: Add cs_hold and cs_inactive setting support spi-cs-inactive-delay-ns in dts is cs_inactive in spi core, and it maps to DLYCS (Minimum Inactive QCS Delay) in QSPI Mode Register (QSPI_MR). spi-cs-hold-delay-ns in dts is cs_hold in spi core, and it maps to DLYBCT (Delay Between Consecutive Transfers) in QSPI_MR. That one can be set to other values than 0 only if the chip is not in Serial Memory Mode (SMM), it must be written to '0' however when in SMM. Tested on SAM9X60 based board with FPGA implementing custom SPI Memory protocol. Signed-off-by: Alexander Dahl Link: https://patch.msgid.link/20240918082744.379610-3-ada@thorsis.com Signed-off-by: Mark Brown --- drivers/spi/atmel-quadspi.c | 36 ++++++++++++++++++++++++++++++++---- 1 file changed, 32 insertions(+), 4 deletions(-) diff --git a/drivers/spi/atmel-quadspi.c b/drivers/spi/atmel-quadspi.c index 20ee227dead29..b328076291891 100644 --- a/drivers/spi/atmel-quadspi.c +++ b/drivers/spi/atmel-quadspi.c @@ -516,21 +516,45 @@ static int atmel_qspi_set_cs_timing(struct spi_device *spi) struct spi_controller *ctrl = spi->controller; struct atmel_qspi *aq = spi_controller_get_devdata(ctrl); unsigned long clk_rate; + u32 cs_inactive; u32 cs_setup; + u32 cs_hold; int delay; int ret; - delay = spi_delay_to_ns(&spi->cs_setup, NULL); - if (delay <= 0) - return delay; - clk_rate = clk_get_rate(aq->pclk); if (!clk_rate) return -EINVAL; + /* hold */ + delay = spi_delay_to_ns(&spi->cs_hold, NULL); + if (aq->mr & QSPI_MR_SMM) { + if (delay > 0) + dev_warn(&aq->pdev->dev, + "Ignoring cs_hold, must be 0 in Serial Memory Mode.\n"); + cs_hold = 0; + } else { + delay = spi_delay_to_ns(&spi->cs_hold, NULL); + if (delay < 0) + return delay; + + cs_hold = DIV_ROUND_UP((delay * DIV_ROUND_UP(clk_rate, 1000000)), 32000); + } + + /* setup */ + delay = spi_delay_to_ns(&spi->cs_setup, NULL); + if (delay < 0) + return delay; + cs_setup = DIV_ROUND_UP((delay * DIV_ROUND_UP(clk_rate, 1000000)), 1000); + /* inactive */ + delay = spi_delay_to_ns(&spi->cs_inactive, NULL); + if (delay < 0) + return delay; + cs_inactive = DIV_ROUND_UP((delay * DIV_ROUND_UP(clk_rate, 1000000)), 1000); + ret = pm_runtime_resume_and_get(ctrl->dev.parent); if (ret < 0) return ret; @@ -539,6 +563,10 @@ static int atmel_qspi_set_cs_timing(struct spi_device *spi) aq->scr |= QSPI_SCR_DLYBS(cs_setup); atmel_qspi_write(aq->scr, aq, QSPI_SCR); + aq->mr &= ~(QSPI_MR_DLYBCT_MASK | QSPI_MR_DLYCS_MASK); + aq->mr |= QSPI_MR_DLYBCT(cs_hold) | QSPI_MR_DLYCS(cs_inactive); + atmel_qspi_write(aq->mr, aq, QSPI_MR); + pm_runtime_mark_last_busy(ctrl->dev.parent); pm_runtime_put_autosuspend(ctrl->dev.parent); -- 2.50.1