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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/drivers/spi/spi-orion.c
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/drivers/spi/spi-orion.c')
-rw-r--r--kernel/drivers/spi/spi-orion.c99
1 files changed, 95 insertions, 4 deletions
diff --git a/kernel/drivers/spi/spi-orion.c b/kernel/drivers/spi/spi-orion.c
index ff97cabda..a87cfd4ba 100644
--- a/kernel/drivers/spi/spi-orion.c
+++ b/kernel/drivers/spi/spi-orion.c
@@ -41,6 +41,11 @@
#define ORION_SPI_DATA_OUT_REG 0x08
#define ORION_SPI_DATA_IN_REG 0x0c
#define ORION_SPI_INT_CAUSE_REG 0x10
+#define ORION_SPI_TIMING_PARAMS_REG 0x18
+
+#define ORION_SPI_TMISO_SAMPLE_MASK (0x3 << 6)
+#define ORION_SPI_TMISO_SAMPLE_1 (1 << 6)
+#define ORION_SPI_TMISO_SAMPLE_2 (2 << 6)
#define ORION_SPI_MODE_CPOL (1 << 11)
#define ORION_SPI_MODE_CPHA (1 << 12)
@@ -70,6 +75,7 @@ struct orion_spi_dev {
unsigned int min_divisor;
unsigned int max_divisor;
u32 prescale_mask;
+ bool is_errata_50mhz_ac;
};
struct orion_spi {
@@ -195,6 +201,41 @@ orion_spi_mode_set(struct spi_device *spi)
writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
}
+static void
+orion_spi_50mhz_ac_timing_erratum(struct spi_device *spi, unsigned int speed)
+{
+ u32 reg;
+ struct orion_spi *orion_spi;
+
+ orion_spi = spi_master_get_devdata(spi->master);
+
+ /*
+ * Erratum description: (Erratum NO. FE-9144572) The device
+ * SPI interface supports frequencies of up to 50 MHz.
+ * However, due to this erratum, when the device core clock is
+ * 250 MHz and the SPI interfaces is configured for 50MHz SPI
+ * clock and CPOL=CPHA=1 there might occur data corruption on
+ * reads from the SPI device.
+ * Erratum Workaround:
+ * Work in one of the following configurations:
+ * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
+ * Register".
+ * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
+ * Register" before setting the interface.
+ */
+ reg = readl(spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
+ reg &= ~ORION_SPI_TMISO_SAMPLE_MASK;
+
+ if (clk_get_rate(orion_spi->clk) == 250000000 &&
+ speed == 50000000 && spi->mode & SPI_CPOL &&
+ spi->mode & SPI_CPHA)
+ reg |= ORION_SPI_TMISO_SAMPLE_2;
+ else
+ reg |= ORION_SPI_TMISO_SAMPLE_1; /* This is the default value */
+
+ writel(reg, spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
+}
+
/*
* called only when no transfer is active on the bus
*/
@@ -216,6 +257,9 @@ orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
orion_spi_mode_set(spi);
+ if (orion_spi->devdata->is_errata_50mhz_ac)
+ orion_spi_50mhz_ac_timing_erratum(spi, speed);
+
rc = orion_spi_baudrate_set(spi, speed);
if (rc)
return rc;
@@ -391,7 +435,7 @@ static const struct orion_spi_dev orion_spi_dev_data = {
.prescale_mask = ORION_SPI_CLK_PRESCALE_MASK,
};
-static const struct orion_spi_dev armada_spi_dev_data = {
+static const struct orion_spi_dev armada_370_spi_dev_data = {
.typ = ARMADA_SPI,
.min_divisor = 4,
.max_divisor = 1920,
@@ -399,9 +443,54 @@ static const struct orion_spi_dev armada_spi_dev_data = {
.prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
};
+static const struct orion_spi_dev armada_xp_spi_dev_data = {
+ .typ = ARMADA_SPI,
+ .max_hz = 50000000,
+ .max_divisor = 1920,
+ .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
+};
+
+static const struct orion_spi_dev armada_375_spi_dev_data = {
+ .typ = ARMADA_SPI,
+ .min_divisor = 15,
+ .max_divisor = 1920,
+ .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
+};
+
+static const struct orion_spi_dev armada_380_spi_dev_data = {
+ .typ = ARMADA_SPI,
+ .max_hz = 50000000,
+ .max_divisor = 1920,
+ .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
+ .is_errata_50mhz_ac = true,
+};
+
static const struct of_device_id orion_spi_of_match_table[] = {
- { .compatible = "marvell,orion-spi", .data = &orion_spi_dev_data, },
- { .compatible = "marvell,armada-370-spi", .data = &armada_spi_dev_data, },
+ {
+ .compatible = "marvell,orion-spi",
+ .data = &orion_spi_dev_data,
+ },
+ {
+ .compatible = "marvell,armada-370-spi",
+ .data = &armada_370_spi_dev_data,
+ },
+ {
+ .compatible = "marvell,armada-375-spi",
+ .data = &armada_375_spi_dev_data,
+ },
+ {
+ .compatible = "marvell,armada-380-spi",
+ .data = &armada_380_spi_dev_data,
+ },
+ {
+ .compatible = "marvell,armada-390-spi",
+ .data = &armada_xp_spi_dev_data,
+ },
+ {
+ .compatible = "marvell,armada-xp-spi",
+ .data = &armada_xp_spi_dev_data,
+ },
+
{}
};
MODULE_DEVICE_TABLE(of, orion_spi_of_match_table);
@@ -473,9 +562,11 @@ static int orion_spi_probe(struct platform_device *pdev)
"marvell,armada-370-spi"))
master->max_speed_hz = min(devdata->max_hz,
DIV_ROUND_UP(tclk_hz, devdata->min_divisor));
- else
+ else if (devdata->min_divisor)
master->max_speed_hz =
DIV_ROUND_UP(tclk_hz, devdata->min_divisor);
+ else
+ master->max_speed_hz = devdata->max_hz;
master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor);
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);