These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / spi / spi-orion.c

diff --git a/kernel/drivers/spi/spi-orion.c b/kernel/drivers/spi/spi-orion.c
index ff97cab..a87cfd4 100644 (file)
--- 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);