The fixmap code from x86 allows us to have compile time virtual addresses
that we change the physical addresses of at run time.
This is useful for applications like kmap_atomic, PCI config that is done
via direct memory map, kexec/kdump.
We got ride of CONFIG_HIGHMEM_START as we can now determine a more optimal
location for PKMAP_BASE based on where the fixmap addresses start and
working back from there.
Additionally, the kmap code in asm-powerpc/highmem.h always had debug
enabled. Moved to using CONFIG_DEBUG_HIGHMEM to determine if we should
have the extra debug checking.
Signed-off-by: Kumar Gala [EMAIL PROTECTED]
---
arch/powerpc/Kconfig | 14 -
arch/powerpc/mm/init_32.c |8 ---
arch/powerpc/mm/mem.c | 32 ++--
arch/powerpc/mm/pgtable_32.c | 23
include/asm-powerpc/fixmap.h | 112 +
include/asm-powerpc/highmem.h | 41 ---
6 files changed, 183 insertions(+), 47 deletions(-)
create mode 100644 include/asm-powerpc/fixmap.h
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 10e9df7..96cc0ad 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -613,20 +613,6 @@ config ADVANCED_OPTIONS
comment Default settings for advanced configuration options are used
depends on !ADVANCED_OPTIONS
-config HIGHMEM_START_BOOL
- bool Set high memory pool address
- depends on ADVANCED_OPTIONS HIGHMEM
- help
- This option allows you to set the base address of the kernel virtual
- area used to map high memory pages. This can be useful in
- optimizing the layout of kernel virtual memory.
-
- Say N here unless you know what you are doing.
-
-config HIGHMEM_START
- hex Virtual start address of high memory pool if HIGHMEM_START_BOOL
- default 0xfe00
-
config LOWMEM_SIZE_BOOL
bool Set maximum low memory
depends on ADVANCED_OPTIONS
diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
index 578750e..1952b4d 100644
--- a/arch/powerpc/mm/init_32.c
+++ b/arch/powerpc/mm/init_32.c
@@ -71,14 +71,6 @@ unsigned long agp_special_page;
EXPORT_SYMBOL(agp_special_page);
#endif
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-pgprot_t kmap_prot;
-
-EXPORT_SYMBOL(kmap_prot);
-EXPORT_SYMBOL(kmap_pte);
-#endif
-
void MMU_init(void);
/* XXX should be in current.h -- paulus */
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 0062e6b..5ccb579 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -45,6 +45,7 @@
#include asm/tlb.h
#include asm/sections.h
#include asm/vdso.h
+#include asm/fixmap.h
#include mmu_decl.h
@@ -57,6 +58,20 @@ int init_bootmem_done;
int mem_init_done;
unsigned long memory_limit;
+#ifdef CONFIG_HIGHMEM
+pte_t *kmap_pte;
+pgprot_t kmap_prot;
+
+EXPORT_SYMBOL(kmap_prot);
+EXPORT_SYMBOL(kmap_pte);
+
+static inline pte_t *virt_to_kpte(unsigned long vaddr)
+{
+ return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
+ vaddr), vaddr), vaddr);
+}
+#endif
+
int page_is_ram(unsigned long pfn)
{
unsigned long paddr = (pfn PAGE_SHIFT);
@@ -311,14 +326,19 @@ void __init paging_init(void)
unsigned long top_of_ram = lmb_end_of_DRAM();
unsigned long max_zone_pfns[MAX_NR_ZONES];
+#ifdef CONFIG_PPC32
+ unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
+ unsigned long end = __fix_to_virt(FIX_HOLE);
+
+ for (; v end; v += PAGE_SIZE)
+ map_page(v, 0, 0); /* XXX gross */
+#endif
+
#ifdef CONFIG_HIGHMEM
map_page(PKMAP_BASE, 0, 0); /* XXX gross */
- pkmap_page_table = pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k
- (PKMAP_BASE), PKMAP_BASE), PKMAP_BASE), PKMAP_BASE);
- map_page(KMAP_FIX_BEGIN, 0, 0); /* XXX gross */
- kmap_pte = pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k
- (KMAP_FIX_BEGIN), KMAP_FIX_BEGIN), KMAP_FIX_BEGIN),
-KMAP_FIX_BEGIN);
+ pkmap_page_table = virt_to_kpte(PKMAP_BASE);
+
+ kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
kmap_prot = PAGE_KERNEL;
#endif /* CONFIG_HIGHMEM */
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 64c44bc..5d0a601 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -29,6 +29,7 @@
#include asm/pgtable.h
#include asm/pgalloc.h
+#include asm/fixmap.h
#include asm/io.h
#include mmu_decl.h
@@ -387,3 +388,25 @@ void kernel_map_pages(struct page *page, int numpages, int
enable)
change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
}
#endif /* CONFIG_DEBUG_PAGEALLOC */
+
+static int fixmaps;
+unsigned long __FIXADDR_TOP = 0xf000;
+EXPORT_SYMBOL(__FIXADDR_TOP);
+
+void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
+{
+ unsigned long address =
