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authorLinus Torvalds <torvalds@linux-foundation.org>2022-08-02 10:55:04 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-08-02 10:55:04 -0700
commit0805c6fb39f66e01cb0adccfae8d9e0615c70fd7 (patch)
treec5aa9d794f06812df4818762a7cbaa78380d9594 /drivers/spi/spi-s3c64xx.c
parent416e05e5b7ce63402a2c342472799d340559f10e (diff)
parent69243df953e70c134c6735b31ba0e658c53d3cda (diff)
Merge tag 'spi-v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown: "The big update this time around is some excellent work from David Jander who went through the fast path and really eliminated overheads, meaning that we are seeing a huge reduction in the time spent between transfers for single threaded clients. Benchmarking has been coming out at about a halving of overhead which is clearly visible in system level usage that stresses SPI like some CAN and IIO applications, especially with small transfers. Thanks to David for taking the time to drill down into this and push the work upstream. Otherwise there's been a bunch of new device support and the usual updates. - Optimisation of the fast path, particularly around the number and types of locking operations, from David Jander. - Support for Arbel NPCM845, HP GXP, Intel Meteor Lake and Thunder Bay, MediaTek MT8188 and MT8365, Microchip FPGAs, nVidia Tegra 241 and Samsung Exynos Auto v9 and 4210" * tag 'spi-v5.20' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (97 commits) MAINTAINERS: add spi support to GXP spi: dt-bindings: add documentation for hpe,gxp-spifi spi: spi-gxp: Add support for HPE GXP SoCs spi: a3700: support BE for AC5 SPI driver spi/panel: dt-bindings: drop CPHA and CPOL from common properties spi: bcm2835: enable shared interrupt support spi: dt-bindings: spi-controller: correct example indentation spi: dt-bindings: qcom,spi-geni-qcom: allow three interconnects spi: npcm-fiu: Add NPCM8XX support dt-binding: spi: Add npcm845 compatible to npcm-fiu document spi: npcm-fiu: Modify direct read dummy configuration spi: atmel: remove #ifdef CONFIG_{PM, SLEEP} spi: dt-bindings: Add compatible for MediaTek MT8188 spi: dt-bindings: mediatek,spi-mtk-nor: Update bindings for nor flash spi: dt-bindings: atmel,at91rm9200-spi: convert to json-schema spi: tegra20-slink: fix UAF in tegra_slink_remove() spi: Fix simplification of devm_spi_register_controller spi: microchip-core: switch to use dev_err_probe() spi: microchip-core: switch to use devm_spi_alloc_master() spi: microchip-core: fix UAF in mchp_corespi_remove() ...
Diffstat (limited to 'drivers/spi/spi-s3c64xx.c')
-rw-r--r--drivers/spi/spi-s3c64xx.c123
1 files changed, 89 insertions, 34 deletions
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index c26440e9058d..7f346866614a 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -18,7 +18,7 @@
#include <linux/platform_data/spi-s3c64xx.h>
-#define MAX_SPI_PORTS 6
+#define MAX_SPI_PORTS 12
#define S3C64XX_SPI_QUIRK_POLL (1 << 0)
#define S3C64XX_SPI_QUIRK_CS_AUTO (1 << 1)
#define AUTOSUSPEND_TIMEOUT 2000
@@ -59,6 +59,7 @@
#define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD (1<<17)
#define S3C64XX_SPI_MODE_BUS_TSZ_WORD (2<<17)
#define S3C64XX_SPI_MODE_BUS_TSZ_MASK (3<<17)
+#define S3C64XX_SPI_MODE_SELF_LOOPBACK (1<<3)
#define S3C64XX_SPI_MODE_RXDMA_ON (1<<2)
#define S3C64XX_SPI_MODE_TXDMA_ON (1<<1)
#define S3C64XX_SPI_MODE_4BURST (1<<0)
@@ -130,11 +131,13 @@ struct s3c64xx_spi_dma_data {
* @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
* @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
* @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
+ * @clk_div: Internal clock divider
* @quirks: Bitmask of known quirks
* @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
* @clk_from_cmu: True, if the controller does not include a clock mux and
* prescaler unit.
* @clk_ioclk: True if clock is present on this device
+ * @has_loopback: True if loopback mode can be supported
*
* The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
* differ in some aspects such as the size of the fifo and spi bus clock
@@ -146,9 +149,11 @@ struct s3c64xx_spi_port_config {
int rx_lvl_offset;
int tx_st_done;
int quirks;
+ int clk_div;
bool high_speed;
bool clk_from_cmu;
bool clk_ioclk;
+ bool has_loopback;
};
/**
@@ -350,19 +355,59 @@ static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
if (is_polling(sdd))
return 0;
+ /* Requests DMA channels */
+ sdd->rx_dma.ch = dma_request_chan(&sdd->pdev->dev, "rx");
+ if (IS_ERR(sdd->rx_dma.ch)) {
+ dev_err(&sdd->pdev->dev, "Failed to get RX DMA channel\n");
+ sdd->rx_dma.ch = NULL;
+ return 0;
+ }
+
+ sdd->tx_dma.ch = dma_request_chan(&sdd->pdev->dev, "tx");
+ if (IS_ERR(sdd->tx_dma.ch)) {
+ dev_err(&sdd->pdev->dev, "Failed to get TX DMA channel\n");
+ dma_release_channel(sdd->rx_dma.ch);
+ sdd->tx_dma.ch = NULL;
+ sdd->rx_dma.ch = NULL;
+ return 0;
+ }
+
spi->dma_rx = sdd->rx_dma.ch;
spi->dma_tx = sdd->tx_dma.ch;
return 0;
}
+static int s3c64xx_spi_unprepare_transfer(struct spi_master *spi)
+{
+ struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
+
+ if (is_polling(sdd))
+ return 0;
+
+ /* Releases DMA channels if they are allocated */
+ if (sdd->rx_dma.ch && sdd->tx_dma.ch) {
+ dma_release_channel(sdd->rx_dma.ch);
+ dma_release_channel(sdd->tx_dma.ch);
+ sdd->rx_dma.ch = 0;
+ sdd->tx_dma.ch = 0;
+ }
+
+ return 0;
+}
+
static bool s3c64xx_spi_can_dma(struct spi_master *master,
struct spi_device *spi,
struct spi_transfer *xfer)
{
struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(master);
- return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
+ if (sdd->rx_dma.ch && sdd->tx_dma.ch) {
+ return xfer->len > (FIFO_LVL_MASK(sdd) >> 1) + 1;
+ } else {
+ return false;
+ }
+
}
static int s3c64xx_enable_datapath(struct s3c64xx_spi_driver_data *sdd,
@@ -577,6 +622,7 @@ static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
void __iomem *regs = sdd->regs;
int ret;
u32 val;
+ int div = sdd->port_conf->clk_div;
/* Disable Clock */
if (!sdd->port_conf->clk_from_cmu) {
@@ -619,19 +665,21 @@ static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
break;
}
+ if ((sdd->cur_mode & SPI_LOOP) && sdd->port_conf->has_loopback)
+ val |= S3C64XX_SPI_MODE_SELF_LOOPBACK;
+
writel(val, regs + S3C64XX_SPI_MODE_CFG);
if (sdd->port_conf->clk_from_cmu) {
- /* The src_clk clock is divided internally by 2 */
- ret = clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
+ ret = clk_set_rate(sdd->src_clk, sdd->cur_speed * div);
if (ret)
return ret;
- sdd->cur_speed = clk_get_rate(sdd->src_clk) / 2;
+ sdd->cur_speed = clk_get_rate(sdd->src_clk) / div;
} else {
/* Configure Clock */
val = readl(regs + S3C64XX_SPI_CLK_CFG);
val &= ~S3C64XX_SPI_PSR_MASK;
- val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / 2 - 1)
+ val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / div - 1)
& S3C64XX_SPI_PSR_MASK);
writel(val, regs + S3C64XX_SPI_CLK_CFG);
@@ -697,7 +745,7 @@ static int s3c64xx_spi_transfer_one(struct spi_master *master,
sdd->rx_dma.ch && sdd->tx_dma.ch) {
use_dma = 1;
- } else if (is_polling(sdd) && xfer->len > fifo_len) {
+ } else if (xfer->len > fifo_len) {
tx_buf = xfer->tx_buf;
rx_buf = xfer->rx_buf;
origin_len = xfer->len;
@@ -825,6 +873,7 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
struct s3c64xx_spi_csinfo *cs = spi->controller_data;
struct s3c64xx_spi_driver_data *sdd;
int err;
+ int div;
sdd = spi_master_get_devdata(spi->master);
if (spi->dev.of_node) {
@@ -843,22 +892,24 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
pm_runtime_get_sync(&sdd->pdev->dev);
+ div = sdd->port_conf->clk_div;
+
/* Check if we can provide the requested rate */
if (!sdd->port_conf->clk_from_cmu) {
u32 psr, speed;
/* Max possible */
- speed = clk_get_rate(sdd->src_clk) / 2 / (0 + 1);
+ speed = clk_get_rate(sdd->src_clk) / div / (0 + 1);
if (spi->max_speed_hz > speed)
spi->max_speed_hz = speed;
- psr = clk_get_rate(sdd->src_clk) / 2 / spi->max_speed_hz - 1;
+ psr = clk_get_rate(sdd->src_clk) / div / spi->max_speed_hz - 1;
psr &= S3C64XX_SPI_PSR_MASK;
if (psr == S3C64XX_SPI_PSR_MASK)
psr--;
- speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
+ speed = clk_get_rate(sdd->src_clk) / div / (psr + 1);
if (spi->max_speed_hz < speed) {
if (psr+1 < S3C64XX_SPI_PSR_MASK) {
psr++;
@@ -868,7 +919,7 @@ static int s3c64xx_spi_setup(struct spi_device *spi)
}
}
- speed = clk_get_rate(sdd->src_clk) / 2 / (psr + 1);
+ speed = clk_get_rate(sdd->src_clk) / div / (psr + 1);
if (spi->max_speed_hz >= speed) {
spi->max_speed_hz = speed;
} else {
@@ -1098,6 +1149,7 @@ static int s3c64xx_spi_probe(struct platform_device *pdev)
master->setup = s3c64xx_spi_setup;
master->cleanup = s3c64xx_spi_cleanup;
master->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
+ master->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
master->prepare_message = s3c64xx_spi_prepare_message;
master->transfer_one = s3c64xx_spi_transfer_one;
master->num_chipselect = sci->num_cs;
@@ -1107,6 +1159,8 @@ static int s3c64xx_spi_probe(struct platform_device *pdev)
SPI_BPW_MASK(8);
/* the spi->mode bits understood by this driver: */
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+ if (sdd->port_conf->has_loopback)
+ master->mode_bits |= SPI_LOOP;
master->auto_runtime_pm = true;
if (!is_polling(sdd))
master->can_dma = s3c64xx_spi_can_dma;
@@ -1167,22 +1221,6 @@ static int s3c64xx_spi_probe(struct platform_device *pdev)
}
}
- if (!is_polling(sdd)) {
- /* Acquire DMA channels */
- sdd->rx_dma.ch = dma_request_chan(&pdev->dev, "rx");
- if (IS_ERR(sdd->rx_dma.ch)) {
- dev_err(&pdev->dev, "Failed to get RX DMA channel\n");
- ret = PTR_ERR(sdd->rx_dma.ch);
- goto err_disable_io_clk;
- }
- sdd->tx_dma.ch = dma_request_chan(&pdev->dev, "tx");
- if (IS_ERR(sdd->tx_dma.ch)) {
- dev_err(&pdev->dev, "Failed to get TX DMA channel\n");
- ret = PTR_ERR(sdd->tx_dma.ch);
- goto err_release_rx_dma;
- }
- }
-
pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_set_active(&pdev->dev);
@@ -1228,12 +1266,6 @@ err_pm_put:
pm_runtime_disable(&pdev->dev);
pm_runtime_set_suspended(&pdev->dev);
- if (!is_polling(sdd))
- dma_release_channel(sdd->tx_dma.ch);
-err_release_rx_dma:
- if (!is_polling(sdd))
- dma_release_channel(sdd->rx_dma.ch);
-err_disable_io_clk:
clk_disable_unprepare(sdd->ioclk);
err_disable_src_clk:
clk_disable_unprepare(sdd->src_clk);
@@ -1369,6 +1401,7 @@ static const struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
.fifo_lvl_mask = { 0x7f },
.rx_lvl_offset = 13,
.tx_st_done = 21,
+ .clk_div = 2,
.high_speed = true,
};
@@ -1376,12 +1409,14 @@ static const struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
.fifo_lvl_mask = { 0x7f, 0x7F },
.rx_lvl_offset = 13,
.tx_st_done = 21,
+ .clk_div = 2,
};
static const struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
.fifo_lvl_mask = { 0x1ff, 0x7F },
.rx_lvl_offset = 15,
.tx_st_done = 25,
+ .clk_div = 2,
.high_speed = true,
};
@@ -1389,6 +1424,7 @@ static const struct s3c64xx_spi_port_config exynos4_spi_port_config = {
.fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F },
.rx_lvl_offset = 15,
.tx_st_done = 25,
+ .clk_div = 2,
.high_speed = true,
.clk_from_cmu = true,
.quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
@@ -1398,6 +1434,7 @@ static const struct s3c64xx_spi_port_config exynos7_spi_port_config = {
.fifo_lvl_mask = { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
.rx_lvl_offset = 15,
.tx_st_done = 25,
+ .clk_div = 2,
.high_speed = true,
.clk_from_cmu = true,
.quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
@@ -1407,16 +1444,31 @@ static const struct s3c64xx_spi_port_config exynos5433_spi_port_config = {
.fifo_lvl_mask = { 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff},
.rx_lvl_offset = 15,
.tx_st_done = 25,
+ .clk_div = 2,
+ .high_speed = true,
+ .clk_from_cmu = true,
+ .clk_ioclk = true,
+ .quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
+};
+
+static const struct s3c64xx_spi_port_config exynosautov9_spi_port_config = {
+ .fifo_lvl_mask = { 0x1ff, 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff, 0x7f,
+ 0x7f, 0x7f, 0x7f, 0x7f},
+ .rx_lvl_offset = 15,
+ .tx_st_done = 25,
+ .clk_div = 4,
.high_speed = true,
.clk_from_cmu = true,
.clk_ioclk = true,
+ .has_loopback = true,
.quirks = S3C64XX_SPI_QUIRK_CS_AUTO,
};
-static struct s3c64xx_spi_port_config fsd_spi_port_config = {
+static const struct s3c64xx_spi_port_config fsd_spi_port_config = {
.fifo_lvl_mask = { 0x7f, 0x7f, 0x7f, 0x7f, 0x7f},
.rx_lvl_offset = 15,
.tx_st_done = 25,
+ .clk_div = 2,
.high_speed = true,
.clk_from_cmu = true,
.clk_ioclk = false,
@@ -1453,6 +1505,9 @@ static const struct of_device_id s3c64xx_spi_dt_match[] = {
{ .compatible = "samsung,exynos5433-spi",
.data = (void *)&exynos5433_spi_port_config,
},
+ { .compatible = "samsung,exynosautov9-spi",
+ .data = (void *)&exynosautov9_spi_port_config,
+ },
{ .compatible = "tesla,fsd-spi",
.data = (void *)&fsd_spi_port_config,
},