[RESPIN v2 5/6] memory: samsung: exynos-srom: Add support for bank configuration

Pankaj Dubey
2016-04-11T07:41:16Z

From: Pavel Fedin <p.fedin@samsung.com>

Implement handling properties in subnodes and adding child devices to the
system. Child devices will not be added if configuration fails.

Since the driver now does more than suspend-resume support, dependency on
CONFIG_PM is removed.

Signed-off-by: Pavel Fedin <p.fedin@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
---
arch/arm/mach-exynos/Kconfig | 2 +-
drivers/memory/samsung/Kconfig | 2 +-
drivers/memory/samsung/exynos-srom.c | 60 ++++++++++++++++++++++++++++++++++--
3 files changed, 60 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig
index 28f9928..e65aa7d 100644
--- a/arch/arm/mach-exynos/Kconfig
+++ b/arch/arm/mach-exynos/Kconfig
@@ -18,7 +18,7 @@ menuconfig ARCH_EXYNOS
select COMMON_CLK_SAMSUNG
select EXYNOS_THERMAL
select EXYNOS_PMU
- select EXYNOS_SROM if PM
+ select EXYNOS_SROM
select HAVE_ARM_SCU if SMP
select HAVE_S3C2410_I2C if I2C
select HAVE_S3C2410_WATCHDOG if WATCHDOG
diff --git a/drivers/memory/samsung/Kconfig b/drivers/memory/samsung/Kconfig
index 64ab5dd..9de1222 100644
--- a/drivers/memory/samsung/Kconfig
+++ b/drivers/memory/samsung/Kconfig
@@ -8,6 +8,6 @@ if SAMSUNG_MC

config EXYNOS_SROM
bool "Exynos SROM controller driver" if COMPILE_TEST
- depends on (ARM && ARCH_EXYNOS && PM) || (COMPILE_TEST && HAS_IOMEM)
+ depends on (ARM && ARCH_EXYNOS) || (COMPILE_TEST && HAS_IOMEM)

endif
diff --git a/drivers/memory/samsung/exynos-srom.c b/drivers/memory/samsung/exynos-srom.c
index 68e073c..96756fb 100644
--- a/drivers/memory/samsung/exynos-srom.c
+++ b/drivers/memory/samsung/exynos-srom.c
@@ -14,6 +14,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
+#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

@@ -67,11 +68,50 @@ static struct exynos_srom_reg_dump *exynos_srom_alloc_reg_dump(
return rd;
}

+static int exynos_srom_configure_bank(struct exynos_srom *srom,
+ struct device_node *np)
+{
+ u32 bank, width, pmc = 0;
+ u32 timing[6];
+ u32 cs, bw;
+
+ if (of_property_read_u32(np, "reg", &bank))
+ return -EINVAL;
+ if (of_property_read_u32(np, "reg-io-width", &width))
+ width = 1;
+ if (of_property_read_bool(np, "samsung,srom-page-mode"))
+ pmc = 1 << EXYNOS_SROM_BCX__PMC__SHIFT;
+ if (of_property_read_u32_array(np, "samsung,srom-timing", timing,
+ ARRAY_SIZE(timing)))
+ return -EINVAL;
+
+ bank *= 4; /* Convert bank into shift/offset */
+
+ cs = 1 << EXYNOS_SROM_BW__BYTEENABLE__SHIFT;
+ if (width == 2)
+ cs |= 1 << EXYNOS_SROM_BW__DATAWIDTH__SHIFT;
+
+ bw = __raw_readl(srom->reg_base + EXYNOS_SROM_BW);
+ bw = (bw & ~(EXYNOS_SROM_BW__CS_MASK << bank)) | (cs << bank);
+ __raw_writel(bw, srom->reg_base + EXYNOS_SROM_BW);
+
+ __raw_writel(pmc | (timing[0] << EXYNOS_SROM_BCX__TACP__SHIFT) |
+ (timing[1] << EXYNOS_SROM_BCX__TCAH__SHIFT) |
+ (timing[2] << EXYNOS_SROM_BCX__TCOH__SHIFT) |
+ (timing[3] << EXYNOS_SROM_BCX__TACC__SHIFT) |
+ (timing[4] << EXYNOS_SROM_BCX__TCOS__SHIFT) |
+ (timing[5] << EXYNOS_SROM_BCX__TACS__SHIFT),
+ srom->reg_base + EXYNOS_SROM_BC0 + bank);
+
+ return 0;
+}
+
static int exynos_srom_probe(struct platform_device *pdev)
{
- struct device_node *np;
+ struct device_node *np, *child;
struct exynos_srom *srom;
struct device *dev = &pdev->dev;
+ bool bad_bank_config = false;

np = dev->of_node;
if (!np) {
@@ -100,7 +140,23 @@ static int exynos_srom_probe(struct platform_device *pdev)
return -ENOMEM;
}

- return 0;
+ for_each_child_of_node(np, child) {
+ if (exynos_srom_configure_bank(srom, child)) {
+ dev_err(dev,
+ "Could not decode bank configuration for %s\n",
+ child->name);
+ bad_bank_config = true;
+ }
+ }
+
+ /*
+ * If any bank failed to configure, we still provide suspend/resume,
+ * but do not probe child devices
+ */
+ if (bad_bank_config)
+ return 0;
+
+ return of_platform_populate(np, NULL, NULL, dev);
}

static int exynos_srom_remove(struct platform_device *pdev)
--
2.4.5