From bba732d86694f7217a41e83a2c1deb42ed9aa7fd Mon Sep 17 00:00:00 2001 From: Franklin S Cooper Jr Date: Wed, 22 Jul 2015 07:32:21 -0500 Subject: [PATCH 1/6] spi: davinci: Set prescale value based on register value Within davinci_spi_get_prescale() the prescale has two meanings. First one being the calculated prescale value and then at the end translates it to the prescale value that will be written to the SPI register. At first glance this can be confusing especially when comparing the minimum prescale value against what is seen in the TRM. To simplify things make it clear that the calculated prescale value will always be based on the value that will be written into the SPI register. Signed-off-by: Franklin S Cooper Jr Signed-off-by: Mark Brown --- drivers/spi/spi-davinci.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c index 987afebea093..b4605c4158f4 100644 --- a/drivers/spi/spi-davinci.c +++ b/drivers/spi/spi-davinci.c @@ -255,7 +255,7 @@ static void davinci_spi_chipselect(struct spi_device *spi, int value) * This function calculates the prescale value that generates a clock rate * less than or equal to the specified maximum. * - * Returns: calculated prescale - 1 for easy programming into SPI registers + * Returns: calculated prescale value for easy programming into SPI registers * or negative error number if valid prescalar cannot be updated. */ static inline int davinci_spi_get_prescale(struct davinci_spi *dspi, @@ -263,12 +263,13 @@ static inline int davinci_spi_get_prescale(struct davinci_spi *dspi, { int ret; - ret = DIV_ROUND_UP(clk_get_rate(dspi->clk), max_speed_hz); + /* Subtract 1 to match what will be programmed into SPI register. */ + ret = DIV_ROUND_UP(clk_get_rate(dspi->clk), max_speed_hz) - 1; - if (ret < 1 || ret > 256) + if (ret < 0 || ret > 255) return -EINVAL; - return ret - 1; + return ret; } /** From fa466c91970a0207d9384016cc7884a7f61834b6 Mon Sep 17 00:00:00 2001 From: Franklin S Cooper Jr Date: Wed, 22 Jul 2015 07:32:22 -0500 Subject: [PATCH 2/6] spi: davinci: Choose correct pre-scaler limit based on SOC Currently the pre-scaler limit is incorrect. The value differs slightly for various devices so a single value can't be used. Using the compatible field select the correct pre-scaler limit. Add new compatible field value for Keystone devices to support their unique pre-scaler limit value. Signed-off-by: Franklin S Cooper Jr Reviewed-by: Sekhar Nori Signed-off-by: Mark Brown --- .../devicetree/bindings/spi/spi-davinci.txt | 2 + drivers/spi/spi-davinci.c | 43 ++++++++++++++++--- include/linux/platform_data/spi-davinci.h | 1 + 3 files changed, 39 insertions(+), 7 deletions(-) diff --git a/Documentation/devicetree/bindings/spi/spi-davinci.txt b/Documentation/devicetree/bindings/spi/spi-davinci.txt index 12ecfe9e3599..d1e914adcf6e 100644 --- a/Documentation/devicetree/bindings/spi/spi-davinci.txt +++ b/Documentation/devicetree/bindings/spi/spi-davinci.txt @@ -12,6 +12,8 @@ Required properties: - compatible: - "ti,dm6441-spi" for SPI used similar to that on DM644x SoC family - "ti,da830-spi" for SPI used similar to that on DA8xx SoC family + - "ti,keystone-spi" for SPI used similar to that on Keystone2 SoC + family - reg: Offset and length of SPI controller register space - num-cs: Number of chip selects. This includes internal as well as GPIO chip selects. diff --git a/drivers/spi/spi-davinci.c b/drivers/spi/spi-davinci.c index b4605c4158f4..3cf9faa6cc3f 100644 --- a/drivers/spi/spi-davinci.c +++ b/drivers/spi/spi-davinci.c @@ -139,6 +139,8 @@ struct davinci_spi { u32 (*get_tx)(struct davinci_spi *); u8 *bytes_per_word; + + u8 prescaler_limit; }; static struct davinci_spi_config davinci_spi_default_cfg; @@ -266,7 +268,7 @@ static inline int davinci_spi_get_prescale(struct davinci_spi *dspi, /* Subtract 1 to match what will be programmed into SPI register. */ ret = DIV_ROUND_UP(clk_get_rate(dspi->clk), max_speed_hz) - 1; - if (ret < 0 || ret > 255) + if (ret < dspi->prescaler_limit || ret > 255) return -EINVAL; return ret; @@ -833,13 +835,40 @@ rx_dma_failed: } #if defined(CONFIG_OF) + +/* OF SPI data structure */ +struct davinci_spi_of_data { + u8 version; + u8 prescaler_limit; +}; + +static const struct davinci_spi_of_data dm6441_spi_data = { + .version = SPI_VERSION_1, + .prescaler_limit = 2, +}; + +static const struct davinci_spi_of_data da830_spi_data = { + .version = SPI_VERSION_2, + .prescaler_limit = 2, +}; + +static const struct davinci_spi_of_data keystone_spi_data = { + .version = SPI_VERSION_1, + .prescaler_limit = 0, +}; + static const struct of_device_id davinci_spi_of_match[] = { { .compatible = "ti,dm6441-spi", + .data = &dm6441_spi_data, }, { .compatible = "ti,da830-spi", - .data = (void *)SPI_VERSION_2, + .data = &da830_spi_data, + }, + { + .compatible = "ti,keystone-spi", + .data = &keystone_spi_data, }, { }, }; @@ -858,21 +887,21 @@ static int spi_davinci_get_pdata(struct platform_device *pdev, struct davinci_spi *dspi) { struct device_node *node = pdev->dev.of_node; + struct davinci_spi_of_data *spi_data; struct davinci_spi_platform_data *pdata; unsigned int num_cs, intr_line = 0; const struct of_device_id *match; pdata = &dspi->pdata; - pdata->version = SPI_VERSION_1; match = of_match_device(davinci_spi_of_match, &pdev->dev); if (!match) return -ENODEV; - /* match data has the SPI version number for SPI_VERSION_2 */ - if (match->data == (void *)SPI_VERSION_2) - pdata->version = SPI_VERSION_2; + spi_data = (struct davinci_spi_of_data *)match->data; + pdata->version = spi_data->version; + pdata->prescaler_limit = spi_data->prescaler_limit; /* * default num_cs is 1 and all chipsel are internal to the chip * indicated by chip_sel being NULL or cs_gpios being NULL or @@ -992,7 +1021,7 @@ static int davinci_spi_probe(struct platform_device *pdev) dspi->bitbang.chipselect = davinci_spi_chipselect; dspi->bitbang.setup_transfer = davinci_spi_setup_transfer; - + dspi->prescaler_limit = pdata->prescaler_limit; dspi->version = pdata->version; dspi->bitbang.flags = SPI_NO_CS | SPI_LSB_FIRST | SPI_LOOP; diff --git a/include/linux/platform_data/spi-davinci.h b/include/linux/platform_data/spi-davinci.h index 8dc2fa47a2aa..f4edcb03c40c 100644 --- a/include/linux/platform_data/spi-davinci.h +++ b/include/linux/platform_data/spi-davinci.h @@ -49,6 +49,7 @@ struct davinci_spi_platform_data { u8 num_chipselect; u8 intr_line; u8 *chip_sel; + u8 prescaler_limit; bool cshold_bug; enum dma_event_q dma_event_q; }; From bdbbd38106c9f72c569be18314f68387e384536c Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Mon, 10 Aug 2015 16:28:07 +0200 Subject: [PATCH 3/6] spi: atmel: remove useless include Definitions from linux/platform_data/atmel.h are not used, remove the include. Signed-off-by: Alexandre Belloni Signed-off-by: Mark Brown --- drivers/spi/spi-atmel.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c index c9eca347787d..bf9ed380bb1c 100644 --- a/drivers/spi/spi-atmel.c +++ b/drivers/spi/spi-atmel.c @@ -19,7 +19,6 @@ #include #include #include -#include #include #include From ca861dd0c5e36c4a2cf454049a45a961c855290a Mon Sep 17 00:00:00 2001 From: Martin Sperl Date: Tue, 28 Jul 2015 14:03:12 +0000 Subject: [PATCH 4/6] spi: bcm2835: set up spi-mode before asserting cs-gpio When using reverse polarity for clock (spi-cpol) on a device the clock line gets altered after chip-select has been asserted resulting in an additional clock beat, which confuses hardware. This did not show when using native-CS, as the same register is used to control cs as well as polarity, so the changes came into effect at the same time. Unfortunately this is not true with gpio-cs. To avoid this situation this patch moves the setup of polarity (spi-cpol and spi-cpha) outside of the chip-select into prepare_message, which is run prior to asserting chip-select. Also fixes resetting 3-wire mode after use of rx-mode, so that a 3-Wire sequence TX, RX, TX works as well (right now it runs TX, RX, RX instead) Reported-by: Noralf Tronnes Signed-off-by: Martin Sperl Signed-off-by: Mark Brown --- drivers/spi/spi-bcm2835.c | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-) diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index 59705ab23577..c9357bb393d3 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -553,13 +553,11 @@ static int bcm2835_spi_transfer_one(struct spi_master *master, spi_used_hz = cdiv ? (clk_hz / cdiv) : (clk_hz / 65536); bcm2835_wr(bs, BCM2835_SPI_CLK, cdiv); - /* handle all the modes */ + /* handle all the 3-wire mode */ if ((spi->mode & SPI_3WIRE) && (tfr->rx_buf)) cs |= BCM2835_SPI_CS_REN; - if (spi->mode & SPI_CPOL) - cs |= BCM2835_SPI_CS_CPOL; - if (spi->mode & SPI_CPHA) - cs |= BCM2835_SPI_CS_CPHA; + else + cs &= ~BCM2835_SPI_CS_REN; /* for gpio_cs set dummy CS so that no HW-CS get changed * we can not run this in bcm2835_spi_set_cs, as it does @@ -592,6 +590,25 @@ static int bcm2835_spi_transfer_one(struct spi_master *master, return bcm2835_spi_transfer_one_irq(master, spi, tfr, cs); } +static int bcm2835_spi_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct spi_device *spi = msg->spi; + struct bcm2835_spi *bs = spi_master_get_devdata(master); + u32 cs = bcm2835_rd(bs, BCM2835_SPI_CS); + + cs &= ~(BCM2835_SPI_CS_CPOL | BCM2835_SPI_CS_CPHA); + + if (spi->mode & SPI_CPOL) + cs |= BCM2835_SPI_CS_CPOL; + if (spi->mode & SPI_CPHA) + cs |= BCM2835_SPI_CS_CPHA; + + bcm2835_wr(bs, BCM2835_SPI_CS, cs); + + return 0; +} + static void bcm2835_spi_handle_err(struct spi_master *master, struct spi_message *msg) { @@ -739,6 +756,7 @@ static int bcm2835_spi_probe(struct platform_device *pdev) master->set_cs = bcm2835_spi_set_cs; master->transfer_one = bcm2835_spi_transfer_one; master->handle_err = bcm2835_spi_handle_err; + master->prepare_message = bcm2835_spi_prepare_message; master->dev.of_node = pdev->dev.of_node; bs = spi_master_get_devdata(master); From 1b0838b5a794456ca36ce02b405bd7bcc85bfba0 Mon Sep 17 00:00:00 2001 From: Franklin S Cooper Jr Date: Wed, 12 Aug 2015 08:26:19 -0500 Subject: [PATCH 5/6] ARM: davinci: Set proper SPI prescale limit value SPI Davinci driver has been updated to allow SOCs to specify their minimum prescale value. Update the various SOCs board files that use this driver with their proper prescaler limit. Acked-by: Sekhar Nori Signed-off-by: Franklin S Cooper Jr Signed-off-by: Mark Brown --- arch/arm/mach-davinci/devices-da8xx.c | 2 ++ arch/arm/mach-davinci/dm355.c | 1 + arch/arm/mach-davinci/dm365.c | 1 + 3 files changed, 4 insertions(+) diff --git a/arch/arm/mach-davinci/devices-da8xx.c b/arch/arm/mach-davinci/devices-da8xx.c index ddfdd820e6f2..29e08aac8294 100644 --- a/arch/arm/mach-davinci/devices-da8xx.c +++ b/arch/arm/mach-davinci/devices-da8xx.c @@ -1010,11 +1010,13 @@ static struct davinci_spi_platform_data da8xx_spi_pdata[] = { .version = SPI_VERSION_2, .intr_line = 1, .dma_event_q = EVENTQ_0, + .prescaler_limit = 2, }, [1] = { .version = SPI_VERSION_2, .intr_line = 1, .dma_event_q = EVENTQ_0, + .prescaler_limit = 2, }, }; diff --git a/arch/arm/mach-davinci/dm355.c b/arch/arm/mach-davinci/dm355.c index 9cbeda798584..567dc56fe8cd 100644 --- a/arch/arm/mach-davinci/dm355.c +++ b/arch/arm/mach-davinci/dm355.c @@ -411,6 +411,7 @@ static struct davinci_spi_platform_data dm355_spi0_pdata = { .num_chipselect = 2, .cshold_bug = true, .dma_event_q = EVENTQ_1, + .prescaler_limit = 1, }; static struct platform_device dm355_spi0_device = { .name = "spi_davinci", diff --git a/arch/arm/mach-davinci/dm365.c b/arch/arm/mach-davinci/dm365.c index e3a3c54b6832..6a890a8486d0 100644 --- a/arch/arm/mach-davinci/dm365.c +++ b/arch/arm/mach-davinci/dm365.c @@ -646,6 +646,7 @@ static struct davinci_spi_platform_data dm365_spi0_pdata = { .version = SPI_VERSION_1, .num_chipselect = 2, .dma_event_q = EVENTQ_3, + .prescaler_limit = 1, }; static struct resource dm365_spi0_resources[] = { From f4d86223771533c68f1a6692d499f7ef0025f733 Mon Sep 17 00:00:00 2001 From: Jonas Gorski Date: Sun, 23 Aug 2015 22:49:32 +0200 Subject: [PATCH 6/6] spi/bcm63xx-hsspi: add support for dual spi read/write Add support for dual read/writes on spi-bcm63xx-hsspi. This has been tested with a s25fl129p1 dual read capable spi flash, with a nice speed improvement: serial read: root@OpenWrt:/# time dd if=/dev/mtd4 of=/dev/null bs=8192 2032+0 records in 2032+0 records out real 0m 4.39s user 0m 0.00s sys 0m 1.55s dual read: root@OpenWrt:/# time dd if=/dev/mtd4 of=/dev/null bs=8192 2032+0 records in 2032+0 records out real 0m 3.09s user 0m 0.00s sys 0m 1.56s Signed-off-by: Jonas Gorski Signed-off-by: Mark Brown --- drivers/spi/spi-bcm63xx-hsspi.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/spi/spi-bcm63xx-hsspi.c b/drivers/spi/spi-bcm63xx-hsspi.c index f5ca6dc3a157..55789f7cda92 100644 --- a/drivers/spi/spi-bcm63xx-hsspi.c +++ b/drivers/spi/spi-bcm63xx-hsspi.c @@ -76,6 +76,7 @@ #define HSSPI_FIFO_REG(x) (0x200 + (x) * 0x200) +#define HSSPI_OP_MULTIBIT BIT(11) #define HSSPI_OP_CODE_SHIFT 13 #define HSSPI_OP_SLEEP (0 << HSSPI_OP_CODE_SHIFT) #define HSSPI_OP_READ_WRITE (1 << HSSPI_OP_CODE_SHIFT) @@ -171,9 +172,12 @@ static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t) if (opcode != HSSPI_OP_READ) step_size -= HSSPI_OPCODE_LEN; - __raw_writel(0 << MODE_CTRL_PREPENDBYTE_CNT_SHIFT | - 2 << MODE_CTRL_MULTIDATA_WR_STRT_SHIFT | - 2 << MODE_CTRL_MULTIDATA_RD_STRT_SHIFT | 0xff, + if ((opcode == HSSPI_OP_READ && t->rx_nbits == SPI_NBITS_DUAL) || + (opcode == HSSPI_OP_WRITE && t->tx_nbits == SPI_NBITS_DUAL)) + opcode |= HSSPI_OP_MULTIBIT; + + __raw_writel(1 << MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT | + 1 << MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT | 0xff, bs->regs + HSSPI_PROFILE_MODE_CTRL_REG(chip_select)); while (pending > 0) { @@ -374,7 +378,8 @@ static int bcm63xx_hsspi_probe(struct platform_device *pdev) master->num_chipselect = 8; master->setup = bcm63xx_hsspi_setup; master->transfer_one_message = bcm63xx_hsspi_transfer_one; - master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; + master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | + SPI_RX_DUAL | SPI_TX_DUAL; master->bits_per_word_mask = SPI_BPW_MASK(8); master->auto_runtime_pm = true;