[PATCH 14/22] ARM: LPAE: accomodate >32-bit addresses for page table base
From: Cyril Chemparathy <hidden>
Date: 2012-07-31 23:05:59
Also in:
lkml
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
This patch redefines the early boot time use of the R4 register to steal a few low order bits (ARCH_PGD_SHIFT bits), allowing for up to 38-bit physical addresses. This is probably not the best means to the end, and a better alternative may be to modify the head.S register allocations to fit in full register pairs for pgdir and swapper_pg_dir. However, squeezing out these extra registers seemed to be a far greater pain than squeezing out a few low order bits from the page table addresses. Signed-off-by: Cyril Chemparathy <redacted> Signed-off-by: Vitaly Andrianov <redacted> --- arch/arm/include/asm/cache.h | 9 +++++++++ arch/arm/kernel/head.S | 7 +++++-- arch/arm/kernel/smp.c | 11 +++++++++-- arch/arm/mm/proc-arm1026.S | 2 ++ arch/arm/mm/proc-mohawk.S | 2 ++ arch/arm/mm/proc-v6.S | 2 ++ arch/arm/mm/proc-v7-2level.S | 2 ++ arch/arm/mm/proc-v7-3level.S | 7 +++++++ arch/arm/mm/proc-v7.S | 1 + arch/arm/mm/proc-xsc3.S | 2 ++ 10 files changed, 41 insertions(+), 4 deletions(-)
diff --git a/arch/arm/include/asm/cache.h b/arch/arm/include/asm/cache.h
index 75fe66b..986480c 100644
--- a/arch/arm/include/asm/cache.h
+++ b/arch/arm/include/asm/cache.h@@ -17,6 +17,15 @@ #define ARCH_DMA_MINALIGN L1_CACHE_BYTES /* + * Minimum guaranted alignment in pgd_alloc(). The page table pointers passed + * around in head.S and proc-*.S are shifted by this amount, in order to + * leave spare high bits for systems with physical address extension. This + * does not fully accomodate the 40-bit addressing capability of ARM LPAE, but + * gives us about 38-bits or so. + */ +#define ARCH_PGD_SHIFT L1_CACHE_SHIFT + +/* * With EABI on ARMv5 and above we must have 64-bit aligned slab pointers. */ #if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5)
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index 7b1a3be..af029ec 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S@@ -22,6 +22,7 @@ #include <asm/memory.h> #include <asm/thread_info.h> #include <asm/pgtable.h> +#include <asm/cache.h> #ifdef CONFIG_DEBUG_LL #include <mach/debug-macro.S>
@@ -163,7 +164,7 @@ ENDPROC(stext) * * Returns: * r0, r3, r5-r7 corrupted - * r4 = physical page table address + * r4 = page table (see ARCH_PGD_SHIFT in asm/cache.h) */ __create_page_tables: pgtbl r4, r8 @ page table address
@@ -323,6 +324,7 @@ __create_page_tables: #ifdef CONFIG_ARM_LPAE sub r4, r4, #0x1000 @ point to the PGD table #endif + mov r4, r4, lsr #ARCH_PGD_SHIFT mov pc, lr ENDPROC(__create_page_tables) .ltorg
@@ -395,7 +397,7 @@ __secondary_data: * r0 = cp#15 control register * r1 = machine ID * r2 = atags or dtb pointer - * r4 = page table pointer + * r4 = page table (see ARCH_PGD_SHIFT in asm/cache.h) * r9 = processor ID * r13 = *virtual* address to jump to upon completion */
@@ -424,6 +426,7 @@ __enable_mmu: @ has the processor setup already programmed the page table pointer? adds r5, r4, #1 + movne r4, r4, lsl #ARCH_PGD_SHIFT mcrne p15, 0, r4, c2, c0, 0 @ load page table pointer b __turn_mmu_on ENDPROC(__enable_mmu)
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
index 2c7217d..e41e1be 100644
--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c@@ -42,6 +42,7 @@ #include <asm/ptrace.h> #include <asm/localtimer.h> #include <asm/smp_plat.h> +#include <asm/cache.h> /* * as from 2.5, kernels no longer have an init_tasks structure
@@ -62,6 +63,7 @@ static DECLARE_COMPLETION(cpu_running); int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) { + phys_addr_t pgdir; int ret; /*
@@ -69,8 +71,13 @@ int __cpuinit __cpu_up(unsigned int cpu, struct task_struct *idle) * its stack and the page tables. */ secondary_data.stack = task_stack_page(idle) + THREAD_START_SP; - secondary_data.pgdir = virt_to_phys(idmap_pgd); - secondary_data.swapper_pg_dir = virt_to_phys(swapper_pg_dir); + + pgdir = virt_to_phys(idmap_pgd); + secondary_data.pgdir = pgdir >> ARCH_PGD_SHIFT; + + pgdir = virt_to_phys(swapper_pg_dir); + secondary_data.swapper_pg_dir = pgdir >> ARCH_PGD_SHIFT; + __cpuc_flush_dcache_area(&secondary_data, sizeof(secondary_data)); outer_clean_range(__pa(&secondary_data), __pa(&secondary_data + 1));
diff --git a/arch/arm/mm/proc-arm1026.S b/arch/arm/mm/proc-arm1026.S
index c28070e..4556f77 100644
--- a/arch/arm/mm/proc-arm1026.S
+++ b/arch/arm/mm/proc-arm1026.S@@ -22,6 +22,7 @@ #include <asm/pgtable-hwdef.h> #include <asm/pgtable.h> #include <asm/ptrace.h> +#include <asm/cache.h> #include "proc-macros.S"
@@ -403,6 +404,7 @@ __arm1026_setup: mcr p15, 0, r0, c7, c10, 4 @ drain write buffer on v4 #ifdef CONFIG_MMU mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs on v4 + mov r4, r4, lsl #ARCH_PGD_SHIFT mcr p15, 0, r4, c2, c0 @ load page table pointer mvn r4, #0 @ do not set page table pointer #endif
diff --git a/arch/arm/mm/proc-mohawk.S b/arch/arm/mm/proc-mohawk.S
index a26303c..13fcc67 100644
--- a/arch/arm/mm/proc-mohawk.S
+++ b/arch/arm/mm/proc-mohawk.S@@ -28,6 +28,7 @@ #include <asm/pgtable.h> #include <asm/page.h> #include <asm/ptrace.h> +#include <asm/cache.h> #include "proc-macros.S" /*
@@ -388,6 +389,7 @@ __mohawk_setup: mcr p15, 0, r0, c7, c7 @ invalidate I,D caches mcr p15, 0, r0, c7, c10, 4 @ drain write buffer mcr p15, 0, r0, c8, c7 @ invalidate I,D TLBs + mov r4, r4, lsl #ARCH_PGD_SHIFT orr r4, r4, #0x18 @ cache the page table in L2 mcr p15, 0, r4, c2, c0, 0 @ load page table pointer mvn r4, #0 @ do not set page table pointer
diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S
index 872156e..4751be7 100644
--- a/arch/arm/mm/proc-v6.S
+++ b/arch/arm/mm/proc-v6.S@@ -17,6 +17,7 @@ #include <asm/hwcap.h> #include <asm/pgtable-hwdef.h> #include <asm/pgtable.h> +#include <asm/cache.h> #include "proc-macros.S"
@@ -206,6 +207,7 @@ __v6_setup: #ifdef CONFIG_MMU mcr p15, 0, r0, c8, c7, 0 @ invalidate I + D TLBs mcr p15, 0, r0, c2, c0, 2 @ TTB control register + mov r4, r4, lsl #ARCH_PGD_SHIFT ALT_SMP(orr r4, r4, #TTB_FLAGS_SMP) ALT_UP(orr r4, r4, #TTB_FLAGS_UP) ALT_SMP(orr r8, r8, #TTB_FLAGS_SMP)
diff --git a/arch/arm/mm/proc-v7-2level.S b/arch/arm/mm/proc-v7-2level.S
index cc78c0c..f4bc63b 100644
--- a/arch/arm/mm/proc-v7-2level.S
+++ b/arch/arm/mm/proc-v7-2level.S@@ -143,8 +143,10 @@ ENDPROC(cpu_v7_set_pte_ext) */ .macro v7_ttb_setup, zero, ttbr0, ttbr1, tmp mcr p15, 0, \zero, c2, c0, 2 @ TTB control register + mov \ttbr0, \ttbr0, lsl #ARCH_PGD_SHIFT ALT_SMP(orr \ttbr0, \ttbr0, #TTB_FLAGS_SMP) ALT_UP(orr \ttbr0, \ttbr0, #TTB_FLAGS_UP) + mov \ttbr1, \ttbr1, lsl #ARCH_PGD_SHIFT ALT_SMP(orr \ttbr1, \ttbr1, #TTB_FLAGS_SMP) ALT_UP(orr \ttbr1, \ttbr1, #TTB_FLAGS_UP) mcr p15, 0, \ttbr0, c2, c0, 0 @ load TTB0
diff --git a/arch/arm/mm/proc-v7-3level.S b/arch/arm/mm/proc-v7-3level.S
index 5e3bed1..33f322a 100644
--- a/arch/arm/mm/proc-v7-3level.S
+++ b/arch/arm/mm/proc-v7-3level.S@@ -103,6 +103,7 @@ ENDPROC(cpu_v7_set_pte_ext) */ .macro v7_ttb_setup, zero, ttbr0, ttbr1, tmp ldr \tmp, =swapper_pg_dir @ swapper_pg_dir virtual address + mov \tmp, \tmp, lsr #ARCH_PGD_SHIFT cmp \ttbr1, \tmp @ PHYS_OFFSET > PAGE_OFFSET? (branch below) mrc p15, 0, \tmp, c2, c0, 2 @ TTB control register orr \tmp, \tmp, #TTB_EAE
@@ -122,8 +123,14 @@ ENDPROC(cpu_v7_set_pte_ext) */ orrls \tmp, \tmp, #TTBR1_SIZE @ TTBCR.T1SZ mcr p15, 0, \tmp, c2, c0, 2 @ TTBCR + mov \tmp, \ttbr1, lsr #(32 - ARCH_PGD_SHIFT) @ upper bits + mov \ttbr1, \ttbr1, lsl #ARCH_PGD_SHIFT @ lower bits addls \ttbr1, \ttbr1, #TTBR1_OFFSET mcrr p15, 1, \ttbr1, \zero, c2 @ load TTBR1 + mov \tmp, \ttbr0, lsr #(32 - ARCH_PGD_SHIFT) @ upper bits + mov \ttbr0, \ttbr0, lsl #ARCH_PGD_SHIFT @ lower bits + mcrr p15, 0, \ttbr0, \zero, c2 @ load TTBR0 + mcrr p15, 1, \ttbr1, \zero, c2 @ load TTBR1 mcrr p15, 0, \ttbr0, \zero, c2 @ load TTBR0 .endm
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index 8850194..443f602 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S@@ -16,6 +16,7 @@ #include <asm/hwcap.h> #include <asm/pgtable-hwdef.h> #include <asm/pgtable.h> +#include <asm/cache.h> #include "proc-macros.S"
diff --git a/arch/arm/mm/proc-xsc3.S b/arch/arm/mm/proc-xsc3.S
index db3836b..a43a07d 100644
--- a/arch/arm/mm/proc-xsc3.S
+++ b/arch/arm/mm/proc-xsc3.S@@ -32,6 +32,7 @@ #include <asm/pgtable-hwdef.h> #include <asm/page.h> #include <asm/ptrace.h> +#include <asm/cache.h> #include "proc-macros.S" /*
@@ -453,6 +454,7 @@ __xsc3_setup: mcr p15, 0, ip, c7, c10, 4 @ data write barrier mcr p15, 0, ip, c7, c5, 4 @ prefetch flush mcr p15, 0, ip, c8, c7, 0 @ invalidate I and D TLBs + mov r4, r4, lsl #ARCH_PGD_SHIFT orr r4, r4, #0x18 @ cache the page table in L2 mcr p15, 0, r4, c2, c0, 0 @ load page table pointer mvn r4, #0 @ do not set page table pointer
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1.7.9.5