[RFC PATCH 09/15] ARM: EXYNOS: fixups for big-endian operation

From: Matthew Leach
Date: Wed Jun 08 2016 - 14:34:26 EST


From: Ben Dooks <ben.dooks@xxxxxxxxxxxxxxx>

If the kernel is built big endian, then using the __raw read and write IO
accessors is not going to work as they end up writing big-endian data to
little-endian IO registers. Fix this by using the readl and writel relaxed
versions which ensure little endian IO.

Signed-off-by: Ben Dooks <ben.dooks@xxxxxxxxxxxxxxx>
---
arch/arm/mach-exynos/firmware.c | 16 ++++++++--------
arch/arm/mach-exynos/headsmp.S | 3 +++
arch/arm/mach-exynos/platsmp.c | 4 ++--
3 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/arch/arm/mach-exynos/firmware.c b/arch/arm/mach-exynos/firmware.c
index 1bfd1b0..96b5e92 100644
--- a/arch/arm/mach-exynos/firmware.c
+++ b/arch/arm/mach-exynos/firmware.c
@@ -41,9 +41,9 @@ static int exynos_do_idle(unsigned long mode)
case FW_DO_IDLE_AFTR:
if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9)
exynos_save_cp15();
- __raw_writel(virt_to_phys(exynos_cpu_resume_ns),
+ writel_relaxed(virt_to_phys(exynos_cpu_resume_ns),
sysram_ns_base_addr + 0x24);
- __raw_writel(EXYNOS_AFTR_MAGIC, sysram_ns_base_addr + 0x20);
+ writel_relaxed(EXYNOS_AFTR_MAGIC, sysram_ns_base_addr + 0x20);
if (soc_is_exynos3250()) {
flush_cache_all();
exynos_smc(SMC_CMD_SAVE, OP_TYPE_CORE,
@@ -97,7 +97,7 @@ static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
if (soc_is_exynos4412())
boot_reg += 4 * cpu;

- __raw_writel(boot_addr, boot_reg);
+ writel_relaxed(boot_addr, boot_reg);
return 0;
}

@@ -113,7 +113,7 @@ static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
if (soc_is_exynos4412())
boot_reg += 4 * cpu;

- *boot_addr = __raw_readl(boot_reg);
+ *boot_addr = readl_relaxed(boot_reg);
return 0;
}

@@ -234,20 +234,20 @@ void exynos_set_boot_flag(unsigned int cpu, unsigned int mode)
{
unsigned int tmp;

- tmp = __raw_readl(REG_CPU_STATE_ADDR + cpu * 4);
+ tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);

if (mode & BOOT_MODE_MASK)
tmp &= ~BOOT_MODE_MASK;

tmp |= mode;
- __raw_writel(tmp, REG_CPU_STATE_ADDR + cpu * 4);
+ writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
}

void exynos_clear_boot_flag(unsigned int cpu, unsigned int mode)
{
unsigned int tmp;

- tmp = __raw_readl(REG_CPU_STATE_ADDR + cpu * 4);
+ tmp = readl_relaxed(REG_CPU_STATE_ADDR + cpu * 4);
tmp &= ~mode;
- __raw_writel(tmp, REG_CPU_STATE_ADDR + cpu * 4);
+ writel_relaxed(tmp, REG_CPU_STATE_ADDR + cpu * 4);
}
diff --git a/arch/arm/mach-exynos/headsmp.S b/arch/arm/mach-exynos/headsmp.S
index b54f970..d3d24ab 100644
--- a/arch/arm/mach-exynos/headsmp.S
+++ b/arch/arm/mach-exynos/headsmp.S
@@ -12,12 +12,15 @@
#include <linux/linkage.h>
#include <linux/init.h>

+#include <asm/assembler.h>
+
/*
* exynos4 specific entry point for secondary CPUs. This provides
* a "holding pen" into which all secondary cores are held until we're
* ready for them to initialise.
*/
ENTRY(exynos4_secondary_startup)
+ARM_BE8(setend be)
mrc p15, 0, r0, c0, c0, 5
and r0, r0, #15
adr r4, 1f
diff --git a/arch/arm/mach-exynos/platsmp.c b/arch/arm/mach-exynos/platsmp.c
index 85c3be6..98ffe1e 100644
--- a/arch/arm/mach-exynos/platsmp.c
+++ b/arch/arm/mach-exynos/platsmp.c
@@ -264,7 +264,7 @@ int exynos_set_boot_addr(u32 core_id, unsigned long boot_addr)
ret = PTR_ERR(boot_reg);
goto fail;
}
- __raw_writel(boot_addr, boot_reg);
+ writel_relaxed(boot_addr, boot_reg);
ret = 0;
}
fail:
@@ -289,7 +289,7 @@ int exynos_get_boot_addr(u32 core_id, unsigned long *boot_addr)
ret = PTR_ERR(boot_reg);
goto fail;
}
- *boot_addr = __raw_readl(boot_reg);
+ *boot_addr = readl_relaxed(boot_reg);
ret = 0;
}
fail:
--
2.8.3