From: Tushar Behera <tushar.behera@linaro.org>
Date: Fri, 9 Aug 2013 08:42:27 +0000 (+0530)
Subject: ARM: EXYNOS: Set 64-bit DMA mask for EXYNOS5250
X-Git-Tag: firefly_0821_release~3680^2~217^2~1^2
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=1288d63721495f64ca6b668d1c1d67e2eefd7b5b;p=firefly-linux-kernel-4.4.55.git

ARM: EXYNOS: Set 64-bit DMA mask for EXYNOS5250

When LPAE is enabled, we need to set 64bit DMA mask bits.

[The actual fix for this issue is a much more involved patch series
reworking how DMA masks are set which is still in review upstream
  -- broonie]

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
---

diff --git a/arch/arm/mach-exynos/mach-exynos5-dt.c b/arch/arm/mach-exynos/mach-exynos5-dt.c
index 753b94f3fca7..d88234e14f96 100644
--- a/arch/arm/mach-exynos/mach-exynos5-dt.c
+++ b/arch/arm/mach-exynos/mach-exynos5-dt.c
@@ -14,6 +14,7 @@
 #include <linux/memblock.h>
 #include <linux/io.h>
 #include <linux/clocksource.h>
+#include <linux/dma-mapping.h>
 
 #include <asm/mach/arch.h>
 #include <mach/regs-pmu.h>
@@ -23,11 +24,31 @@
 
 #include "common.h"
 
+static u64 dma_mask64 = DMA_BIT_MASK(64);
+
 static void __init exynos5_dt_map_io(void)
 {
 	exynos_init_io(NULL, 0);
 }
 
+static int exynos5250_platform_notifier(struct notifier_block *nb,
+				  unsigned long event, void *__dev)
+{
+	struct device *dev = __dev;
+
+	if (event != BUS_NOTIFY_ADD_DEVICE)
+		return NOTIFY_DONE;
+
+	dev->dma_mask = &dma_mask64;
+	dev->coherent_dma_mask = DMA_BIT_MASK(64);
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block exynos5250_platform_nb = {
+	.notifier_call = exynos5250_platform_notifier,
+};
+
 static void __init exynos5_dt_machine_init(void)
 {
 	struct device_node *i2c_np;
@@ -52,6 +73,11 @@ static void __init exynos5_dt_machine_init(void)
 		}
 	}
 
+	if (config_enabled(CONFIG_ARM_LPAE) &&
+			of_machine_is_compatible("samsung,exynos5250"))
+		bus_register_notifier(&platform_bus_type,
+				&exynos5250_platform_nb);
+
 	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
 }