sh: Isolate uncached mapping support.
This splits out the uncached mapping support under its own config option,
presently only used by 29-bit mode and 32-bit + PMB. This will make it
possible to optionally add an uncached mapping on sh64 as well as booting
without an uncached mapping for 32-bit.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/include/asm/ptrace.h b/arch/sh/include/asm/ptrace.h
index 201d11e..e879dff 100644
--- a/arch/sh/include/asm/ptrace.h
+++ b/arch/sh/include/asm/ptrace.h
@@ -102,13 +102,15 @@
#define PTRACE_GETDSPREGS 55 /* DSP registers */
#define PTRACE_SETDSPREGS 56
-#define PT_TEXT_END_ADDR 240
-#define PT_TEXT_ADDR 244 /* &(struct user)->start_code */
-#define PT_DATA_ADDR 248 /* &(struct user)->start_data */
+#define PT_TEXT_END_ADDR 240
+#define PT_TEXT_ADDR 244 /* &(struct user)->start_code */
+#define PT_DATA_ADDR 248 /* &(struct user)->start_data */
#define PT_TEXT_LEN 252
#ifdef __KERNEL__
#include <asm/addrspace.h>
+#include <asm/page.h>
+#include <asm/system.h>
#define user_mode(regs) (((regs)->sr & 0x40000000)==0)
#define instruction_pointer(regs) ((unsigned long)(regs)->pc)
@@ -137,9 +139,14 @@
{
unsigned long pc = instruction_pointer(regs);
-#ifdef P2SEG
- if (pc >= P2SEG && pc < P3SEG)
- pc -= 0x20000000;
+#ifdef CONFIG_UNCACHED_MAPPING
+ /*
+ * If PC points in to the uncached mapping, fix it up and hand
+ * back the cached equivalent.
+ */
+ if ((pc >= (memory_start + cached_to_uncached)) &&
+ (pc < (memory_start + cached_to_uncached + uncached_size)))
+ pc -= cached_to_uncached;
#endif
return pc;
diff --git a/arch/sh/include/asm/system.h b/arch/sh/include/asm/system.h
index 6442f17..0bd7a17 100644
--- a/arch/sh/include/asm/system.h
+++ b/arch/sh/include/asm/system.h
@@ -10,7 +10,6 @@
#include <linux/compiler.h>
#include <linux/linkage.h>
#include <asm/types.h>
-#include <asm/ptrace.h>
#define AT_VECTOR_SIZE_ARCH 5 /* entries in ARCH_DLINFO */
@@ -114,6 +113,8 @@
(unsigned long)_n_, sizeof(*(ptr))); \
})
+struct pt_regs;
+
extern void die(const char *str, struct pt_regs *regs, long err) __attribute__ ((noreturn));
void free_initmem(void);
void free_initrd_mem(unsigned long start, unsigned long end);
diff --git a/arch/sh/include/asm/system_64.h b/arch/sh/include/asm/system_64.h
index 3391bb6..3633864 100644
--- a/arch/sh/include/asm/system_64.h
+++ b/arch/sh/include/asm/system_64.h
@@ -18,6 +18,7 @@
/*
* switch_to() should switch tasks to task nr n, first
*/
+struct thread_struct;
struct task_struct *sh64_switch_to(struct task_struct *prev,
struct thread_struct *prev_thread,
struct task_struct *next,
diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index b890752..65cb5b8 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -75,6 +75,7 @@
config 29BIT
def_bool !32BIT
depends on SUPERH32
+ select UNCACHED_MAPPING
config 32BIT
bool
@@ -84,6 +85,7 @@
bool "Support 32-bit physical addressing through PMB"
depends on MMU && EXPERIMENTAL && CPU_SH4A && !CPU_SH4AL_DSP
select 32BIT
+ select UNCACHED_MAPPING
help
If you say Y here, physical addressing will be extended to
32-bits through the SH-4A PMB. If this is not set, legacy
@@ -173,6 +175,9 @@
def_bool y
depends on X2TLB || SUPERH64
+config UNCACHED_MAPPING
+ bool
+
choice
prompt "Kernel page size"
default PAGE_SIZE_4KB
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index dffa6c7..58012b6 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -21,11 +21,12 @@
#include <asm/cacheflush.h>
#include <asm/sections.h>
#include <asm/cache.h>
+#include <asm/sizes.h>
DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
pgd_t swapper_pg_dir[PTRS_PER_PGD];
-#ifdef CONFIG_SUPERH32
+#ifdef CONFIG_UNCACHED_MAPPING
/*
* This is the offset of the uncached section from its cached alias.
*
@@ -36,8 +37,8 @@
* Default value only valid in 29 bit mode, in 32bit mode this will be
* updated by the early PMB initialization code.
*/
-unsigned long cached_to_uncached = P2SEG - P1SEG;
-unsigned long uncached_size = 0x20000000;
+unsigned long cached_to_uncached = 0x20000000;
+unsigned long uncached_size = SZ_512M;
#endif
#ifdef CONFIG_MMU
@@ -281,7 +282,9 @@
#endif
" vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n"
" lowmem : 0x%08lx - 0x%08lx (%4ld MB) (cached)\n"
+#ifdef CONFIG_UNCACHED_MAPPING
" : 0x%08lx - 0x%08lx (%4ld MB) (uncached)\n"
+#endif
" .init : 0x%08lx - 0x%08lx (%4ld kB)\n"
" .data : 0x%08lx - 0x%08lx (%4ld kB)\n"
" .text : 0x%08lx - 0x%08lx (%4ld kB)\n",
@@ -299,9 +302,11 @@
(unsigned long)memory_start, (unsigned long)high_memory,
((unsigned long)high_memory - (unsigned long)memory_start) >> 20,
+#ifdef CONFIG_UNCACHED_MAPPING
(unsigned long)memory_start + cached_to_uncached,
(unsigned long)memory_start + cached_to_uncached + uncached_size,
uncached_size >> 20,
+#endif
(unsigned long)&__init_begin, (unsigned long)&__init_end,
((unsigned long)&__init_end -