From f131a0800e286a13839784e554383c0ddfa78bce Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 1 Oct 2010 15:42:02 +0100 Subject: ARM: no need for nommu to jump through the hoops that mmu does nommu can jump directly to __mmap_switched without the absolute address branching which the mmuful kernel does. Acked-by: Greg Ungerer Signed-off-by: Russell King --- arch/arm/kernel/head-nommu.S | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/arch/arm/kernel/head-nommu.S b/arch/arm/kernel/head-nommu.S index 573b803dc6bf..814ce1a73270 100644 --- a/arch/arm/kernel/head-nommu.S +++ b/arch/arm/kernel/head-nommu.S @@ -48,8 +48,6 @@ ENTRY(stext) movs r8, r5 @ invalid machine (r5=0)? beq __error_a @ yes, error 'a' - ldr r13, __switch_data @ address to jump to after - @ the initialization is done adr lr, BSYM(__after_proc_init) @ return (PIC) address ARM( add pc, r10, #PROCINFO_INITFUNC ) THUMB( add r12, r10, #PROCINFO_INITFUNC ) @@ -87,8 +85,7 @@ __after_proc_init: mcr p15, 0, r0, c1, c0, 0 @ write control reg #endif /* CONFIG_CPU_CP15 */ - mov r3, r13 - mov pc, r3 @ clear the BSS and jump + b __mmap_switched @ clear the BSS and jump @ to start_kernel ENDPROC(__after_proc_init) .ltorg -- cgit From 37b05b63754e995b8cb76f4fbe7ed7219b3ca896 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 1 Oct 2010 15:38:24 +0100 Subject: ARM: hotplug cpu: setup 1:1 map for entire kernel image for secondary CPUs Make the entire kernel image available for secondary CPUs rather than just the first MB of memory. This allows the startup code to appear in the cpuinit sections. Signed-off-by: Russell King --- arch/arm/kernel/smp.c | 63 ++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 55 insertions(+), 8 deletions(-) diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 40dc74f2b27f..14070549e051 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include #include @@ -67,12 +68,47 @@ enum ipi_msg_type { IPI_CPU_STOP, }; +static inline void identity_mapping_add(pgd_t *pgd, unsigned long start, + unsigned long end) +{ + unsigned long addr, prot; + pmd_t *pmd; + + prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE; + if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale()) + prot |= PMD_BIT4; + + for (addr = start & PGDIR_MASK; addr < end;) { + pmd = pmd_offset(pgd + pgd_index(addr), addr); + pmd[0] = __pmd(addr | prot); + addr += SECTION_SIZE; + pmd[1] = __pmd(addr | prot); + addr += SECTION_SIZE; + flush_pmd_entry(pmd); + outer_clean_range(__pa(pmd), __pa(pmd + 1)); + } +} + +static inline void identity_mapping_del(pgd_t *pgd, unsigned long start, + unsigned long end) +{ + unsigned long addr; + pmd_t *pmd; + + for (addr = start & PGDIR_MASK; addr < end; addr += PGDIR_SIZE) { + pmd = pmd_offset(pgd + pgd_index(addr), addr); + pmd[0] = __pmd(0); + pmd[1] = __pmd(0); + clean_pmd_entry(pmd); + outer_clean_range(__pa(pmd), __pa(pmd + 1)); + } +} + int __cpuinit __cpu_up(unsigned int cpu) { struct cpuinfo_arm *ci = &per_cpu(cpu_data, cpu); struct task_struct *idle = ci->idle; pgd_t *pgd; - pmd_t *pmd; int ret; /* @@ -101,11 +137,16 @@ int __cpuinit __cpu_up(unsigned int cpu) * a 1:1 mapping for the physical address of the kernel. */ pgd = pgd_alloc(&init_mm); - pmd = pmd_offset(pgd + pgd_index(PHYS_OFFSET), PHYS_OFFSET); - *pmd = __pmd((PHYS_OFFSET & PGDIR_MASK) | - PMD_TYPE_SECT | PMD_SECT_AP_WRITE); - flush_pmd_entry(pmd); - outer_clean_range(__pa(pmd), __pa(pmd + 1)); + if (!pgd) + return -ENOMEM; + + if (PHYS_OFFSET != PAGE_OFFSET) { +#ifndef CONFIG_HOTPLUG_CPU + identity_mapping_add(pgd, __pa(__init_begin), __pa(__init_end)); +#endif + identity_mapping_add(pgd, __pa(_stext), __pa(_etext)); + identity_mapping_add(pgd, __pa(_sdata), __pa(_edata)); + } /* * We need to tell the secondary core where to find @@ -143,8 +184,14 @@ int __cpuinit __cpu_up(unsigned int cpu) secondary_data.stack = NULL; secondary_data.pgdir = 0; - *pmd = __pmd(0); - clean_pmd_entry(pmd); + if (PHYS_OFFSET != PAGE_OFFSET) { +#ifndef CONFIG_HOTPLUG_CPU + identity_mapping_del(pgd, __pa(__init_begin), __pa(__init_end)); +#endif + identity_mapping_del(pgd, __pa(_stext), __pa(_etext)); + identity_mapping_del(pgd, __pa(_sdata), __pa(_edata)); + } + pgd_free(&init_mm, pgd); if (ret) { -- cgit From 5085f3ff458521045f7e43da62b8c30ea7df2e82 Mon Sep 17 00:00:00 2001 From: Russell King Date: Fri, 1 Oct 2010 15:37:05 +0100 Subject: ARM: hotplug cpu: Keep processor information, startup code & __lookup_processor_type When hotplug CPU is enabled, we need to keep the list of supported CPUs, their setup functions, and __lookup_processor_type in place so that we can find and initialize secondary CPUs. Move these into the __CPUINIT section. Signed-off-by: Russell King --- arch/arm/kernel/head-common.S | 81 ++++++++++++++++++++++++------------------- arch/arm/kernel/vmlinux.lds.S | 24 +++++++++---- arch/arm/mm/proc-arm1020.S | 2 +- arch/arm/mm/proc-arm1020e.S | 2 +- arch/arm/mm/proc-arm1022.S | 2 +- arch/arm/mm/proc-arm1026.S | 2 +- arch/arm/mm/proc-arm6_7.S | 2 +- arch/arm/mm/proc-arm720.S | 2 +- arch/arm/mm/proc-arm740.S | 2 +- arch/arm/mm/proc-arm7tdmi.S | 2 +- arch/arm/mm/proc-arm920.S | 2 +- arch/arm/mm/proc-arm922.S | 2 +- arch/arm/mm/proc-arm925.S | 2 +- arch/arm/mm/proc-arm926.S | 2 +- arch/arm/mm/proc-arm940.S | 2 +- arch/arm/mm/proc-arm946.S | 2 +- arch/arm/mm/proc-arm9tdmi.S | 2 +- arch/arm/mm/proc-fa526.S | 2 +- arch/arm/mm/proc-feroceon.S | 2 +- arch/arm/mm/proc-mohawk.S | 2 +- arch/arm/mm/proc-sa110.S | 2 +- arch/arm/mm/proc-sa1100.S | 2 +- arch/arm/mm/proc-v6.S | 6 +++- arch/arm/mm/proc-v7.S | 6 +++- arch/arm/mm/proc-xsc3.S | 2 +- arch/arm/mm/proc-xscale.S | 2 +- 26 files changed, 94 insertions(+), 67 deletions(-) diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index b9505aa267c0..6ad24d2cb14b 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -145,45 +145,14 @@ ENDPROC(__error) /* - * Read processor ID register (CP#15, CR0), and look up in the linker-built - * supported processor list. Note that we can't use the absolute addresses - * for the __proc_info lists since we aren't running with the MMU on - * (and therefore, we are not in the correct address space). We have to - * calculate the offset. - * - * r9 = cpuid - * Returns: - * r3, r4, r6 corrupted - * r5 = proc_info pointer in physical address space - * r9 = cpuid (preserved) - */ -__lookup_processor_type: - adr r3, 3f - ldmia r3, {r5 - r7} - add r3, r3, #8 - sub r3, r3, r7 @ get offset between virt&phys - add r5, r5, r3 @ convert virt addresses to - add r6, r6, r3 @ physical address space -1: ldmia r5, {r3, r4} @ value, mask - and r4, r4, r9 @ mask wanted bits - teq r3, r4 - beq 2f - add r5, r5, #PROC_INFO_SZ @ sizeof(proc_info_list) - cmp r5, r6 - blo 1b - mov r5, #0 @ unknown processor -2: mov pc, lr -ENDPROC(__lookup_processor_type) - -/* - * This provides a C-API version of the above function. + * This provides a C-API version of __lookup_processor_type */ ENTRY(lookup_processor_type) - stmfd sp!, {r4 - r7, r9, lr} + stmfd sp!, {r4 - r6, r9, lr} mov r9, r0 bl __lookup_processor_type mov r0, r5 - ldmfd sp!, {r4 - r7, r9, pc} + ldmfd sp!, {r4 - r6, r9, pc} ENDPROC(lookup_processor_type) /* @@ -191,8 +160,6 @@ ENDPROC(lookup_processor_type) * more information about the __proc_info and __arch_info structures. */ .align 2 -3: .long __proc_info_begin - .long __proc_info_end 4: .long . .long __arch_info_begin .long __arch_info_end @@ -265,3 +232,45 @@ __vet_atags: 1: mov r2, #0 mov pc, lr ENDPROC(__vet_atags) + +/* + * Read processor ID register (CP#15, CR0), and look up in the linker-built + * supported processor list. Note that we can't use the absolute addresses + * for the __proc_info lists since we aren't running with the MMU on + * (and therefore, we are not in the correct address space). We have to + * calculate the offset. + * + * r9 = cpuid + * Returns: + * r3, r4, r6 corrupted + * r5 = proc_info pointer in physical address space + * r9 = cpuid (preserved) + */ + __CPUINIT +__lookup_processor_type: + adr r3, __lookup_processor_type_data + ldmia r3, {r4 - r6} + sub r3, r3, r4 @ get offset between virt&phys + add r5, r5, r3 @ convert virt addresses to + add r6, r6, r3 @ physical address space +1: ldmia r5, {r3, r4} @ value, mask + and r4, r4, r9 @ mask wanted bits + teq r3, r4 + beq 2f + add r5, r5, #PROC_INFO_SZ @ sizeof(proc_info_list) + cmp r5, r6 + blo 1b + mov r5, #0 @ unknown processor +2: mov pc, lr +ENDPROC(__lookup_processor_type) + +/* + * Look in for information about the __proc_info structure. + */ + .align 2 + .type __lookup_processor_type_data, %object +__lookup_processor_type_data: + .long . + .long __proc_info_begin + .long __proc_info_end + .size __lookup_processor_type_data, . - __lookup_processor_type_data diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index b16c07914b55..1630524a3097 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -8,6 +8,19 @@ #include #include +#define PROC_INFO \ + VMLINUX_SYMBOL(__proc_info_begin) = .; \ + *(.proc.info.init) \ + VMLINUX_SYMBOL(__proc_info_end) = .; + +#ifdef CONFIG_HOTPLUG_CPU +#define ARM_CPU_DISCARD(x) +#define ARM_CPU_KEEP(x) x +#else +#define ARM_CPU_DISCARD(x) x +#define ARM_CPU_KEEP(x) +#endif + OUTPUT_ARCH(arm) ENTRY(stext) @@ -31,9 +44,7 @@ SECTIONS HEAD_TEXT INIT_TEXT _einittext = .; - __proc_info_begin = .; - *(.proc.info.init) - __proc_info_end = .; + ARM_CPU_DISCARD(PROC_INFO) __arch_info_begin = .; *(.arch.info.init) __arch_info_end = .; @@ -68,10 +79,8 @@ SECTIONS /DISCARD/ : { *(.ARM.exidx.exit.text) *(.ARM.extab.exit.text) -#ifndef CONFIG_HOTPLUG_CPU - *(.ARM.exidx.cpuexit.text) - *(.ARM.extab.cpuexit.text) -#endif + ARM_CPU_DISCARD(*(.ARM.exidx.cpuexit.text)) + ARM_CPU_DISCARD(*(.ARM.extab.cpuexit.text)) #ifndef CONFIG_HOTPLUG *(.ARM.exidx.devexit.text) *(.ARM.extab.devexit.text) @@ -100,6 +109,7 @@ SECTIONS *(.glue_7) *(.glue_7t) *(.got) /* Global offset table */ + ARM_CPU_KEEP(PROC_INFO) } RO_DATA(PAGE_SIZE) diff --git a/arch/arm/mm/proc-arm1020.S b/arch/arm/mm/proc-arm1020.S index 203a4e944d9e..a6f5f8475b96 100644 --- a/arch/arm/mm/proc-arm1020.S +++ b/arch/arm/mm/proc-arm1020.S @@ -430,7 +430,7 @@ ENTRY(cpu_arm1020_set_pte_ext) #endif /* CONFIG_MMU */ mov pc, lr - __INIT + __CPUINIT .type __arm1020_setup, #function __arm1020_setup: diff --git a/arch/arm/mm/proc-arm1020e.S b/arch/arm/mm/proc-arm1020e.S index 1a511e765909..afc06b9c3133 100644 --- a/arch/arm/mm/proc-arm1020e.S +++ b/arch/arm/mm/proc-arm1020e.S @@ -412,7 +412,7 @@ ENTRY(cpu_arm1020e_set_pte_ext) #endif /* CONFIG_MMU */ mov pc, lr - __INIT + __CPUINIT .type __arm1020e_setup, #function __arm1020e_setup: diff --git a/arch/arm/mm/proc-arm1022.S b/arch/arm/mm/proc-arm1022.S index 1ffa4eb9c34f..8915e0ba3fe5 100644 --- a/arch/arm/mm/proc-arm1022.S +++ b/arch/arm/mm/proc-arm1022.S @@ -394,7 +394,7 @@ ENTRY(cpu_arm1022_set_pte_ext) #endif /* CONFIG_MMU */ mov pc, lr - __INIT + __CPUINIT .type __arm1022_setup, #function __arm1022_setup: diff --git a/arch/arm/mm/proc-arm1026.S b/arch/arm/mm/proc-arm1026.S index 5697c34b95b0..ff446c5d476f 100644 --- a/arch/arm/mm/proc-arm1026.S +++ b/arch/arm/mm/proc-arm1026.S @@ -384,7 +384,7 @@ ENTRY(cpu_arm1026_set_pte_ext) mov pc, lr - __INIT + __CPUINIT .type __arm1026_setup, #function __arm1026_setup: diff --git a/arch/arm/mm/proc-arm6_7.S b/arch/arm/mm/proc-arm6_7.S index 64e0b327c7c5..6a7be1863edd 100644 --- a/arch/arm/mm/proc-arm6_7.S +++ b/arch/arm/mm/proc-arm6_7.S @@ -238,7 +238,7 @@ ENTRY(cpu_arm7_reset) mcr p15, 0, r1, c1, c0, 0 @ turn off MMU etc mov pc, r0 - __INIT + __CPUINIT .type __arm6_setup, #function __arm6_setup: mov r0, #0 diff --git a/arch/arm/mm/proc-arm720.S b/arch/arm/mm/proc-arm720.S index 9d96824134fc..c285395f44b2 100644 --- a/arch/arm/mm/proc-arm720.S +++ b/arch/arm/mm/proc-arm720.S @@ -113,7 +113,7 @@ ENTRY(cpu_arm720_reset) mcr p15, 0, ip, c1, c0, 0 @ ctrl register mov pc, r0 - __INIT + __CPUINIT .type __arm710_setup, #function __arm710_setup: diff --git a/arch/arm/mm/proc-arm740.S b/arch/arm/mm/proc-arm740.S index 6c1a9ab059ae..38b27dcba727 100644 --- a/arch/arm/mm/proc-arm740.S +++ b/arch/arm/mm/proc-arm740.S @@ -55,7 +55,7 @@ ENTRY(cpu_arm740_reset) mcr p15, 0, ip, c1, c0, 0 @ ctrl register mov pc, r0 - __INIT + __CPUINIT .type __arm740_setup, #function __arm740_setup: diff --git a/arch/arm/mm/proc-arm7tdmi.S b/arch/arm/mm/proc-arm7tdmi.S index 6a850dbba22e..0c9786de20af 100644 --- a/arch/arm/mm/proc-arm7tdmi.S +++ b/arch/arm/mm/proc-arm7tdmi.S @@ -46,7 +46,7 @@ ENTRY(cpu_arm7tdmi_proc_fin) ENTRY(cpu_arm7tdmi_reset) mov pc, r0 - __INIT + __CPUINIT .type __arm7tdmi_setup, #function __arm7tdmi_setup: diff --git a/arch/arm/mm/proc-arm920.S b/arch/arm/mm/proc-arm920.S index 86f80aa56216..fecf570939f3 100644 --- a/arch/arm/mm/proc-arm920.S +++ b/arch/arm/mm/proc-arm920.S @@ -375,7 +375,7 @@ ENTRY(cpu_arm920_set_pte_ext) #endif mov pc, lr - __INIT + __CPUINIT .type __arm920_setup, #function __arm920_setup: diff --git a/arch/arm/mm/proc-arm922.S b/arch/arm/mm/proc-arm922.S index f76ce9b62883..e3cbf87c9480 100644 --- a/arch/arm/mm/proc-arm922.S +++ b/arch/arm/mm/proc-arm922.S @@ -379,7 +379,7 @@ ENTRY(cpu_arm922_set_pte_ext) #endif /* CONFIG_MMU */ mov pc, lr - __INIT + __CPUINIT .type __arm922_setup, #function __arm922_setup: diff --git a/arch/arm/mm/proc-arm925.S b/arch/arm/mm/proc-arm925.S index 657bd3f7c153..572424c867b5 100644 --- a/arch/arm/mm/proc-arm925.S +++ b/arch/arm/mm/proc-arm925.S @@ -428,7 +428,7 @@ ENTRY(cpu_arm925_set_pte_ext) #endif /* CONFIG_MMU */ mov pc, lr - __INIT + __CPUINIT .type __arm925_setup, #function __arm925_setup: diff --git a/arch/arm/mm/proc-arm926.S b/arch/arm/mm/proc-arm926.S index 73f1f3c68910..63d168b4ebe6 100644 --- a/arch/arm/mm/proc-arm926.S +++ b/arch/arm/mm/proc-arm926.S @@ -389,7 +389,7 @@ ENTRY(cpu_arm926_set_pte_ext) #endif mov pc, lr - __INIT + __CPUINIT .type __arm926_setup, #function __arm926_setup: diff --git a/arch/arm/mm/proc-arm940.S b/arch/arm/mm/proc-arm940.S index fffb061a45a5..f6a62822418e 100644 --- a/arch/arm/mm/proc-arm940.S +++ b/arch/arm/mm/proc-arm940.S @@ -264,7 +264,7 @@ ENTRY(arm940_cache_fns) .long arm940_dma_unmap_area .long arm940_dma_flush_range - __INIT + __CPUINIT .type __arm940_setup, #function __arm940_setup: diff --git a/arch/arm/mm/proc-arm946.S b/arch/arm/mm/proc-arm946.S index 249a6053760a..ea2e7f2eb95b 100644 --- a/arch/arm/mm/proc-arm946.S +++ b/arch/arm/mm/proc-arm946.S @@ -317,7 +317,7 @@ ENTRY(cpu_arm946_dcache_clean_area) mcr p15, 0, r0, c7, c10, 4 @ drain WB mov pc, lr - __INIT + __CPUINIT .type __arm946_setup, #function __arm946_setup: diff --git a/arch/arm/mm/proc-arm9tdmi.S b/arch/arm/mm/proc-arm9tdmi.S index db475667fac2..db67e3134d7a 100644 --- a/arch/arm/mm/proc-arm9tdmi.S +++ b/arch/arm/mm/proc-arm9tdmi.S @@ -46,7 +46,7 @@ ENTRY(cpu_arm9tdmi_proc_fin) ENTRY(cpu_arm9tdmi_reset) mov pc, r0 - __INIT + __CPUINIT .type __arm9tdmi_setup, #function __arm9tdmi_setup: diff --git a/arch/arm/mm/proc-fa526.S b/arch/arm/mm/proc-fa526.S index 7803fdf70029..7c9ad621f0e6 100644 --- a/arch/arm/mm/proc-fa526.S +++ b/arch/arm/mm/proc-fa526.S @@ -134,7 +134,7 @@ ENTRY(cpu_fa526_set_pte_ext) #endif mov pc, lr - __INIT + __CPUINIT .type __fa526_setup, #function __fa526_setup: diff --git a/arch/arm/mm/proc-feroceon.S b/arch/arm/mm/proc-feroceon.S index b304d0104a4e..578da69200cf 100644 --- a/arch/arm/mm/proc-feroceon.S +++ b/arch/arm/mm/proc-feroceon.S @@ -494,7 +494,7 @@ ENTRY(cpu_feroceon_set_pte_ext) #endif mov pc, lr - __INIT + __CPUINIT .type __feroceon_setup, #function __feroceon_setup: diff --git a/arch/arm/mm/proc-mohawk.S b/arch/arm/mm/proc-mohawk.S index 5f6892fcc167..4458ee6aa713 100644 --- a/arch/arm/mm/proc-mohawk.S +++ b/arch/arm/mm/proc-mohawk.S @@ -338,7 +338,7 @@ ENTRY(cpu_mohawk_set_pte_ext) mcr p15, 0, r0, c7, c10, 4 @ drain WB mov pc, lr - __INIT + __CPUINIT .type __mohawk_setup, #function __mohawk_setup: diff --git a/arch/arm/mm/proc-sa110.S b/arch/arm/mm/proc-sa110.S index a201eb04b5e1..5aa8d59c2e85 100644 --- a/arch/arm/mm/proc-sa110.S +++ b/arch/arm/mm/proc-sa110.S @@ -156,7 +156,7 @@ ENTRY(cpu_sa110_set_pte_ext) #endif mov pc, lr - __INIT + __CPUINIT .type __sa110_setup, #function __sa110_setup: diff --git a/arch/arm/mm/proc-sa1100.S b/arch/arm/mm/proc-sa1100.S index 7ddc4805bf97..2ac4e6f10713 100644 --- a/arch/arm/mm/proc-sa1100.S +++ b/arch/arm/mm/proc-sa1100.S @@ -169,7 +169,7 @@ ENTRY(cpu_sa1100_set_pte_ext) #endif mov pc, lr - __INIT + __CPUINIT .type __sa1100_setup, #function __sa1100_setup: diff --git a/arch/arm/mm/proc-v6.S b/arch/arm/mm/proc-v6.S index 22aac8515196..037d1a47ea98 100644 --- a/arch/arm/mm/proc-v6.S +++ b/arch/arm/mm/proc-v6.S @@ -137,7 +137,7 @@ cpu_pj4_name: .align - __INIT + __CPUINIT /* * __v6_setup @@ -192,6 +192,8 @@ __v6_setup: v6_crval: crval clear=0x01e0fb7f, mmuset=0x00c0387d, ucset=0x00c0187c + __INITDATA + .type v6_processor_functions, #object ENTRY(v6_processor_functions) .word v6_early_abort @@ -205,6 +207,8 @@ ENTRY(v6_processor_functions) .word cpu_v6_set_pte_ext .size v6_processor_functions, . - v6_processor_functions + .section ".rodata" + .type cpu_arch_name, #object cpu_arch_name: .asciz "armv6" diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S index 6a8506d99ee9..cd15adb9b2e4 100644 --- a/arch/arm/mm/proc-v7.S +++ b/arch/arm/mm/proc-v7.S @@ -169,7 +169,7 @@ cpu_v7_name: .ascii "ARMv7 Processor" .align - __INIT + __CPUINIT /* * __v7_setup @@ -297,6 +297,8 @@ v7_crval: __v7_setup_stack: .space 4 * 11 @ 11 registers + __INITDATA + .type v7_processor_functions, #object ENTRY(v7_processor_functions) .word v7_early_abort @@ -310,6 +312,8 @@ ENTRY(v7_processor_functions) .word cpu_v7_set_pte_ext .size v7_processor_functions, . - v7_processor_functions + .section ".rodata" + .type cpu_arch_name, #object cpu_arch_name: .asciz "armv7" diff --git a/arch/arm/mm/proc-xsc3.S b/arch/arm/mm/proc-xsc3.S index 361a51e49030..cad07e403044 100644 --- a/arch/arm/mm/proc-xsc3.S +++ b/arch/arm/mm/proc-xsc3.S @@ -404,7 +404,7 @@ ENTRY(cpu_xsc3_set_pte_ext) .align - __INIT + __CPUINIT .type __xsc3_setup, #function __xsc3_setup: diff --git a/arch/arm/mm/proc-xscale.S b/arch/arm/mm/proc-xscale.S index 14075979bcba..cb245edb2c2b 100644 --- a/arch/arm/mm/proc-xscale.S +++ b/arch/arm/mm/proc-xscale.S @@ -506,7 +506,7 @@ ENTRY(cpu_xscale_set_pte_ext) .align - __INIT + __CPUINIT .type __xscale_setup, #function __xscale_setup: -- cgit From a4ae41341fd39af6e25ec9861a6a4dc0c5c58b16 Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 4 Oct 2010 16:22:34 +0100 Subject: ARM: cleanup boot cpu calling __mmap_switched This allows us to relocate __mmap_switched and associated data away from the head section. Signed-off-by: Russell King --- arch/arm/kernel/head-common.S | 3 +-- arch/arm/kernel/head.S | 3 ++- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 6ad24d2cb14b..9f473ef2a64c 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -18,7 +18,6 @@ .align 2 .type __switch_data, %object __switch_data: - .long __mmap_switched .long __data_loc @ r4 .long _data @ r5 .long __bss_start @ r6 @@ -39,7 +38,7 @@ __switch_data: * r9 = processor ID */ __mmap_switched: - adr r3, __switch_data + 4 + adr r3, __switch_data ldmia r3!, {r4, r5, r6, r7} cmp r4, r5 @ Copy data segment if needed diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index eb62bf947212..aa6ab9d86461 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -95,13 +95,14 @@ ENTRY(stext) * above. On return, the CPU will be ready for the MMU to be * turned on, and r0 will hold the CPU control register value. */ - ldr r13, __switch_data @ address to jump to after + ldr r13, =__mmap_switched @ address to jump to after @ mmu has been enabled adr lr, BSYM(__enable_mmu) @ return (PIC) address ARM( add pc, r10, #PROCINFO_INITFUNC ) THUMB( add r12, r10, #PROCINFO_INITFUNC ) THUMB( mov pc, r12 ) ENDPROC(stext) + .ltorg #if defined(CONFIG_SMP) ENTRY(secondary_startup) -- cgit From 17bb5e2c1706c7296eec96e97be0d760e59f282c Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 4 Oct 2010 16:29:35 +0100 Subject: ARM: move __mmap_switched, C-API functions to init section Move these functions, which are only ever used during boot CPU initialization, to the init section. Signed-off-by: Russell King --- arch/arm/kernel/head-common.S | 142 +++++++++++++++++++++--------------------- 1 file changed, 72 insertions(+), 70 deletions(-) diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 9f473ef2a64c..24dfa14b0bf9 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -15,54 +15,6 @@ #define ATAG_CORE_SIZE ((2*4 + 3*4) >> 2) #define ATAG_CORE_SIZE_EMPTY ((2*4) >> 2) - .align 2 - .type __switch_data, %object -__switch_data: - .long __data_loc @ r4 - .long _data @ r5 - .long __bss_start @ r6 - .long _end @ r7 - .long processor_id @ r4 - .long __machine_arch_type @ r5 - .long __atags_pointer @ r6 - .long cr_alignment @ r7 - .long init_thread_union + THREAD_START_SP @ sp - -/* - * The following fragment of code is executed with the MMU on in MMU mode, - * and uses absolute addresses; this is not position independent. - * - * r0 = cp#15 control register - * r1 = machine ID - * r2 = atags pointer - * r9 = processor ID - */ -__mmap_switched: - adr r3, __switch_data - - ldmia r3!, {r4, r5, r6, r7} - cmp r4, r5 @ Copy data segment if needed -1: cmpne r5, r6 - ldrne fp, [r4], #4 - strne fp, [r5], #4 - bne 1b - - mov fp, #0 @ Clear BSS (and zero fp) -1: cmp r6, r7 - strcc fp, [r6],#4 - bcc 1b - - ARM( ldmia r3, {r4, r5, r6, r7, sp}) - THUMB( ldmia r3, {r4, r5, r6, r7} ) - THUMB( ldr sp, [r3, #16] ) - str r9, [r4] @ Save processor ID - str r1, [r5] @ Save machine type - str r2, [r6] @ Save atags pointer - bic r4, r0, #CR_A @ Clear 'A' bit - stmia r7, {r0, r4} @ Save control register values - b start_kernel -ENDPROC(__mmap_switched) - /* * Exception handling. Something went wrong and we can't proceed. We * ought to tell the user, but since we don't have any guarantee that @@ -143,17 +95,6 @@ __error: ENDPROC(__error) -/* - * This provides a C-API version of __lookup_processor_type - */ -ENTRY(lookup_processor_type) - stmfd sp!, {r4 - r6, r9, lr} - mov r9, r0 - bl __lookup_processor_type - mov r0, r5 - ldmfd sp!, {r4 - r6, r9, pc} -ENDPROC(lookup_processor_type) - /* * Look in and arch/arm/kernel/arch.[ch] for * more information about the __proc_info and __arch_info structures. @@ -190,17 +131,6 @@ __lookup_machine_type: 2: mov pc, lr ENDPROC(__lookup_machine_type) -/* - * This provides a C-API version of the above function. - */ -ENTRY(lookup_machine_type) - stmfd sp!, {r4 - r6, lr} - mov r1, r0 - bl __lookup_machine_type - mov r0, r5 - ldmfd sp!, {r4 - r6, pc} -ENDPROC(lookup_machine_type) - /* Determine validity of the r2 atags pointer. The heuristic requires * that the pointer be aligned, in the first 16k of physical RAM and * that the ATAG_CORE marker is first and present. Future revisions @@ -232,6 +162,78 @@ __vet_atags: mov pc, lr ENDPROC(__vet_atags) +/* + * The following fragment of code is executed with the MMU on in MMU mode, + * and uses absolute addresses; this is not position independent. + * + * r0 = cp#15 control register + * r1 = machine ID + * r2 = atags pointer + * r9 = processor ID + */ + __INIT +__mmap_switched: + adr r3, __mmap_switched_data + + ldmia r3!, {r4, r5, r6, r7} + cmp r4, r5 @ Copy data segment if needed +1: cmpne r5, r6 + ldrne fp, [r4], #4 + strne fp, [r5], #4 + bne 1b + + mov fp, #0 @ Clear BSS (and zero fp) +1: cmp r6, r7 + strcc fp, [r6],#4 + bcc 1b + + ARM( ldmia r3, {r4, r5, r6, r7, sp}) + THUMB( ldmia r3, {r4, r5, r6, r7} ) + THUMB( ldr sp, [r3, #16] ) + str r9, [r4] @ Save processor ID + str r1, [r5] @ Save machine type + str r2, [r6] @ Save atags pointer + bic r4, r0, #CR_A @ Clear 'A' bit + stmia r7, {r0, r4} @ Save control register values + b start_kernel +ENDPROC(__mmap_switched) + + .align 2 + .type __mmap_switched_data, %object +__mmap_switched_data: + .long __data_loc @ r4 + .long _data @ r5 + .long __bss_start @ r6 + .long _end @ r7 + .long processor_id @ r4 + .long __machine_arch_type @ r5 + .long __atags_pointer @ r6 + .long cr_alignment @ r7 + .long init_thread_union + THREAD_START_SP @ sp + .size __mmap_switched_data, . - __mmap_switched_data + +/* + * This provides a C-API version of __lookup_machine_type + */ +ENTRY(lookup_machine_type) + stmfd sp!, {r4 - r6, lr} + mov r1, r0 + bl __lookup_machine_type + mov r0, r5 + ldmfd sp!, {r4 - r6, pc} +ENDPROC(lookup_machine_type) + +/* + * This provides a C-API version of __lookup_processor_type + */ +ENTRY(lookup_processor_type) + stmfd sp!, {r4 - r6, r9, lr} + mov r9, r0 + bl __lookup_processor_type + mov r0, r5 + ldmfd sp!, {r4 - r6, r9, pc} +ENDPROC(lookup_processor_type) + /* * Read processor ID register (CP#15, CR0), and look up in the linker-built * supported processor list. Note that we can't use the absolute addresses -- cgit From c083c6609b290a650894f846270a9233401adc22 Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 4 Oct 2010 17:39:20 +0100 Subject: ARM: hotplug cpu: move __error and __error_p to cpuinit section __error and __error_p may be used by secondary CPUs, so these need to be in the cpuinit section. Signed-off-by: Russell King --- arch/arm/kernel/head-common.S | 67 +++++++++++++++++++++---------------------- 1 file changed, 33 insertions(+), 34 deletions(-) diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 24dfa14b0bf9..7c6f9ab47b95 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -24,21 +24,6 @@ * and hope for the best (useful if bootloader fails to pass a proper * machine ID for example). */ -__error_p: -#ifdef CONFIG_DEBUG_LL - adr r0, str_p1 - bl printascii - mov r0, r9 - bl printhex8 - adr r0, str_p2 - bl printascii - b __error -str_p1: .asciz "\nError: unrecognized/unsupported processor variant (0x" -str_p2: .asciz ").\n" - .align -#endif -ENDPROC(__error_p) - __error_a: #ifdef CONFIG_DEBUG_LL mov r4, r1 @ preserve machine ID @@ -76,25 +61,6 @@ str_a3: .asciz "\nPlease check your kernel config and/or bootloader.\n" .align #endif -__error: -#ifdef CONFIG_ARCH_RPC -/* - * Turn the screen red on a error - RiscPC only. - */ - mov r0, #0x02000000 - mov r3, #0x11 - orr r3, r3, r3, lsl #8 - orr r3, r3, r3, lsl #16 - str r3, [r0], #4 - str r3, [r0], #4 - str r3, [r0], #4 - str r3, [r0], #4 -#endif -1: mov r0, r0 - b 1b -ENDPROC(__error) - - /* * Look in and arch/arm/kernel/arch.[ch] for * more information about the __proc_info and __arch_info structures. @@ -275,3 +241,36 @@ __lookup_processor_type_data: .long __proc_info_begin .long __proc_info_end .size __lookup_processor_type_data, . - __lookup_processor_type_data + +__error_p: +#ifdef CONFIG_DEBUG_LL + adr r0, str_p1 + bl printascii + mov r0, r9 + bl printhex8 + adr r0, str_p2 + bl printascii + b __error +str_p1: .asciz "\nError: unrecognized/unsupported processor variant (0x" +str_p2: .asciz ").\n" + .align +#endif +ENDPROC(__error_p) + +__error: +#ifdef CONFIG_ARCH_RPC +/* + * Turn the screen red on a error - RiscPC only. + */ + mov r0, #0x02000000 + mov r3, #0x11 + orr r3, r3, r3, lsl #8 + orr r3, r3, r3, lsl #16 + str r3, [r0], #4 + str r3, [r0], #4 + str r3, [r0], #4 + str r3, [r0], #4 +#endif +1: mov r0, r0 + b 1b +ENDPROC(__error) -- cgit From 80924ac595f3ca32ec0a80cc1217c7019d3519ff Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 4 Oct 2010 17:45:25 +0100 Subject: ARM: cleanup lookup_machine_type data and ensure these are placed in __HEAD Signed-off-by: Russell King --- arch/arm/kernel/head-common.S | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/arch/arm/kernel/head-common.S b/arch/arm/kernel/head-common.S index 7c6f9ab47b95..c4effcfba1eb 100644 --- a/arch/arm/kernel/head-common.S +++ b/arch/arm/kernel/head-common.S @@ -24,6 +24,7 @@ * and hope for the best (useful if bootloader fails to pass a proper * machine ID for example). */ + __HEAD __error_a: #ifdef CONFIG_DEBUG_LL mov r4, r1 @ preserve machine ID @@ -33,7 +34,7 @@ __error_a: bl printhex8 adr r0, str_a2 bl printascii - adr r3, 4f + adr r3, __lookup_machine_type_data ldmia r3, {r4, r5, r6} @ get machine desc list sub r4, r3, r4 @ get offset between virt&phys add r5, r5, r4 @ convert virt addresses to @@ -61,15 +62,6 @@ str_a3: .asciz "\nPlease check your kernel config and/or bootloader.\n" .align #endif -/* - * Look in and arch/arm/kernel/arch.[ch] for - * more information about the __proc_info and __arch_info structures. - */ - .align 2 -4: .long . - .long __arch_info_begin - .long __arch_info_end - /* * Lookup machine architecture in the linker-build list of architectures. * Note that we can't use the absolute addresses for the __arch_info @@ -82,7 +74,7 @@ str_a3: .asciz "\nPlease check your kernel config and/or bootloader.\n" * r5 = mach_info pointer in physical address space */ __lookup_machine_type: - adr r3, 4b + adr r3, __lookup_machine_type_data ldmia r3, {r4, r5, r6} sub r3, r3, r4 @ get offset between virt&phys add r5, r5, r3 @ convert virt addresses to @@ -97,6 +89,18 @@ __lookup_machine_type: 2: mov pc, lr ENDPROC(__lookup_machine_type) +/* + * Look in arch/arm/kernel/arch.[ch] for information about the + * __arch_info structures. + */ + .align 2 + .type __lookup_machine_type_data, %object +__lookup_machine_type_data: + .long . + .long __arch_info_begin + .long __arch_info_end + .size __lookup_machine_type_data, . - __lookup_machine_type_data + /* Determine validity of the r2 atags pointer. The heuristic requires * that the pointer be aligned, in the first 16k of physical RAM and * that the ATAG_CORE marker is first and present. Future revisions -- cgit From 786f1b73f7d5cad5c88dc75a96d53a74160aa7d7 Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 4 Oct 2010 17:51:54 +0100 Subject: ARM: hotplug cpu: ensure that __enable_mmu is identity mapped __enable_mmu is required to be executed in an identity mapped region to ensure that variances in CPUs do not cause a crash. We currently achieve this by assuming that it will be co-located with __create_page_tables. With hotplug CPU support, this assumption becomes invalid. Implement a better solution which ensures that it will be appropriately mapped no matter where it is placed. Signed-off-by: Russell King --- arch/arm/kernel/head.S | 33 ++++++++++++++++++++++++--------- 1 file changed, 24 insertions(+), 9 deletions(-) diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index aa6ab9d86461..17414e299482 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -201,6 +201,7 @@ __turn_mmu_on: mov r3, r3 mov r3, r13 mov pc, r3 +__enable_mmu_end: ENDPROC(__turn_mmu_on) @@ -214,7 +215,7 @@ ENDPROC(__turn_mmu_on) * r10 = procinfo * * Returns: - * r0, r3, r6, r7 corrupted + * r0, r3, r5-r7 corrupted * r4 = physical page table address */ __create_page_tables: @@ -236,20 +237,30 @@ __create_page_tables: ldr r7, [r10, #PROCINFO_MM_MMUFLAGS] @ mm_mmuflags /* - * Create identity mapping for first MB of kernel to - * cater for the MMU enable. This identity mapping - * will be removed by paging_init(). We use our current program - * counter to determine corresponding section base address. + * Create identity mapping to cater for __enable_mmu. + * This identity mapping will be removed by paging_init(). */ - mov r6, pc - mov r6, r6, lsr #20 @ start of kernel section - orr r3, r7, r6, lsl #20 @ flags + kernel base - str r3, [r4, r6, lsl #2] @ identity mapping + adr r0, __enable_mmu_loc + ldmia r0, {r3, r5, r6} + sub r0, r0, r3 @ virt->phys offset + add r5, r5, r0 @ phys __enable_mmu + add r6, r6, r0 @ phys __enable_mmu_end + mov r5, r5, lsr #20 + mov r6, r6, lsr #20 + +1: orr r3, r7, r5, lsl #20 @ flags + kernel base + str r3, [r4, r5, lsl #2] @ identity mapping + teq r5, r6 + addne r5, r5, #1 @ next section + bne 1b /* * Now setup the pagetables for our kernel direct * mapped region. */ + mov r3, pc + mov r3, r3, lsr #20 + orr r3, r7, r3, lsl #20 add r0, r4, #(KERNEL_START & 0xff000000) >> 18 str r3, [r0, #(KERNEL_START & 0x00f00000) >> 18]! ldr r6, =(KERNEL_END - 1) @@ -333,5 +344,9 @@ __create_page_tables: mov pc, lr ENDPROC(__create_page_tables) .ltorg +__enable_mmu_loc: + .long . + .long __enable_mmu + .long __enable_mmu_end #include "head-common.S" -- cgit From 00945010c063b95e813b966f44bf58ffa1955a38 Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 4 Oct 2010 17:56:13 +0100 Subject: ARM: hotplug cpu: move secondary_startup, __enable_mmu to cpuinit Move these two functions, both of which are required for secondary CPU booting, into the cpuinit section. Ensure bad processors call __error_p for better diagnostics, rather than just __error. Signed-off-by: Russell King --- arch/arm/kernel/head.S | 206 +++++++++++++++++++++++++------------------------ 1 file changed, 104 insertions(+), 102 deletions(-) diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index 17414e299482..ed9ebe59178b 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -97,114 +97,14 @@ ENTRY(stext) */ ldr r13, =__mmap_switched @ address to jump to after @ mmu has been enabled - adr lr, BSYM(__enable_mmu) @ return (PIC) address + adr lr, BSYM(1f) @ return (PIC) address ARM( add pc, r10, #PROCINFO_INITFUNC ) THUMB( add r12, r10, #PROCINFO_INITFUNC ) THUMB( mov pc, r12 ) +1: b __enable_mmu ENDPROC(stext) .ltorg -#if defined(CONFIG_SMP) -ENTRY(secondary_startup) - /* - * Common entry point for secondary CPUs. - * - * Ensure that we're in SVC mode, and IRQs are disabled. Lookup - * the processor type - there is no need to check the machine type - * as it has already been validated by the primary processor. - */ - setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 - mrc p15, 0, r9, c0, c0 @ get processor id - bl __lookup_processor_type - movs r10, r5 @ invalid processor? - moveq r0, #'p' @ yes, error 'p' - beq __error - - /* - * Use the page tables supplied from __cpu_up. - */ - adr r4, __secondary_data - ldmia r4, {r5, r7, r12} @ address to jump to after - sub r4, r4, r5 @ mmu has been enabled - ldr r4, [r7, r4] @ get secondary_data.pgdir - adr lr, BSYM(__enable_mmu) @ return address - mov r13, r12 @ __secondary_switched address - ARM( add pc, r10, #PROCINFO_INITFUNC ) @ initialise processor - @ (return control reg) - THUMB( add r12, r10, #PROCINFO_INITFUNC ) - THUMB( mov pc, r12 ) -ENDPROC(secondary_startup) - - /* - * r6 = &secondary_data - */ -ENTRY(__secondary_switched) - ldr sp, [r7, #4] @ get secondary_data.stack - mov fp, #0 - b secondary_start_kernel -ENDPROC(__secondary_switched) - - .type __secondary_data, %object -__secondary_data: - .long . - .long secondary_data - .long __secondary_switched -#endif /* defined(CONFIG_SMP) */ - - - -/* - * Setup common bits before finally enabling the MMU. Essentially - * this is just loading the page table pointer and domain access - * registers. - */ -__enable_mmu: -#ifdef CONFIG_ALIGNMENT_TRAP - orr r0, r0, #CR_A -#else - bic r0, r0, #CR_A -#endif -#ifdef CONFIG_CPU_DCACHE_DISABLE - bic r0, r0, #CR_C -#endif -#ifdef CONFIG_CPU_BPREDICT_DISABLE - bic r0, r0, #CR_Z -#endif -#ifdef CONFIG_CPU_ICACHE_DISABLE - bic r0, r0, #CR_I -#endif - mov r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \ - domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \ - domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \ - domain_val(DOMAIN_IO, DOMAIN_CLIENT)) - mcr p15, 0, r5, c3, c0, 0 @ load domain access register - mcr p15, 0, r4, c2, c0, 0 @ load page table pointer - b __turn_mmu_on -ENDPROC(__enable_mmu) - -/* - * Enable the MMU. This completely changes the structure of the visible - * memory space. You will not be able to trace execution through this. - * If you have an enquiry about this, *please* check the linux-arm-kernel - * mailing list archives BEFORE sending another post to the list. - * - * r0 = cp#15 control register - * r13 = *virtual* address to jump to upon completion - * - * other registers depend on the function called upon completion - */ - .align 5 -__turn_mmu_on: - mov r0, r0 - mcr p15, 0, r0, c1, c0, 0 @ write control reg - mrc p15, 0, r3, c0, c0, 0 @ read id reg - mov r3, r3 - mov r3, r13 - mov pc, r3 -__enable_mmu_end: -ENDPROC(__turn_mmu_on) - - /* * Setup the initial page tables. We only setup the barest * amount which are required to get the kernel running, which @@ -349,4 +249,106 @@ __enable_mmu_loc: .long __enable_mmu .long __enable_mmu_end +#if defined(CONFIG_SMP) + __CPUINIT +ENTRY(secondary_startup) + /* + * Common entry point for secondary CPUs. + * + * Ensure that we're in SVC mode, and IRQs are disabled. Lookup + * the processor type - there is no need to check the machine type + * as it has already been validated by the primary processor. + */ + setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 + mrc p15, 0, r9, c0, c0 @ get processor id + bl __lookup_processor_type + movs r10, r5 @ invalid processor? + moveq r0, #'p' @ yes, error 'p' + beq __error_p + + /* + * Use the page tables supplied from __cpu_up. + */ + adr r4, __secondary_data + ldmia r4, {r5, r7, r12} @ address to jump to after + sub r4, r4, r5 @ mmu has been enabled + ldr r4, [r7, r4] @ get secondary_data.pgdir + adr lr, BSYM(__enable_mmu) @ return address + mov r13, r12 @ __secondary_switched address + ARM( add pc, r10, #PROCINFO_INITFUNC ) @ initialise processor + @ (return control reg) + THUMB( add r12, r10, #PROCINFO_INITFUNC ) + THUMB( mov pc, r12 ) +ENDPROC(secondary_startup) + + /* + * r6 = &secondary_data + */ +ENTRY(__secondary_switched) + ldr sp, [r7, #4] @ get secondary_data.stack + mov fp, #0 + b secondary_start_kernel +ENDPROC(__secondary_switched) + + .type __secondary_data, %object +__secondary_data: + .long . + .long secondary_data + .long __secondary_switched +#endif /* defined(CONFIG_SMP) */ + + + +/* + * Setup common bits before finally enabling the MMU. Essentially + * this is just loading the page table pointer and domain access + * registers. + */ +__enable_mmu: +#ifdef CONFIG_ALIGNMENT_TRAP + orr r0, r0, #CR_A +#else + bic r0, r0, #CR_A +#endif +#ifdef CONFIG_CPU_DCACHE_DISABLE + bic r0, r0, #CR_C +#endif +#ifdef CONFIG_CPU_BPREDICT_DISABLE + bic r0, r0, #CR_Z +#endif +#ifdef CONFIG_CPU_ICACHE_DISABLE + bic r0, r0, #CR_I +#endif + mov r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \ + domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \ + domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \ + domain_val(DOMAIN_IO, DOMAIN_CLIENT)) + mcr p15, 0, r5, c3, c0, 0 @ load domain access register + mcr p15, 0, r4, c2, c0, 0 @ load page table pointer + b __turn_mmu_on +ENDPROC(__enable_mmu) + +/* + * Enable the MMU. This completely changes the structure of the visible + * memory space. You will not be able to trace execution through this. + * If you have an enquiry about this, *please* check the linux-arm-kernel + * mailing list archives BEFORE sending another post to the list. + * + * r0 = cp#15 control register + * r13 = *virtual* address to jump to upon completion + * + * other registers depend on the function called upon completion + */ + .align 5 +__turn_mmu_on: + mov r0, r0 + mcr p15, 0, r0, c1, c0, 0 @ write control reg + mrc p15, 0, r3, c0, c0, 0 @ read id reg + mov r3, r3 + mov r3, r13 + mov pc, r3 +__enable_mmu_end: +ENDPROC(__turn_mmu_on) + + #include "head-common.S" -- cgit From 865a4fae7793b80e2b8bca76e279d6dfecbeac17 Mon Sep 17 00:00:00 2001 From: Russell King Date: Mon, 4 Oct 2010 18:02:59 +0100 Subject: ARM: add register documentation for __enable_mmu Add some additional documentation on register usage in __enable_mmu to help complete the overall picture. Signed-off-by: Russell King --- arch/arm/kernel/head.S | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S index ed9ebe59178b..c11dd14afc11 100644 --- a/arch/arm/kernel/head.S +++ b/arch/arm/kernel/head.S @@ -303,6 +303,13 @@ __secondary_data: * Setup common bits before finally enabling the MMU. Essentially * this is just loading the page table pointer and domain access * registers. + * + * r0 = cp#15 control register + * r1 = machine ID + * r2 = atags pointer + * r4 = page table pointer + * r9 = processor ID + * r13 = *virtual* address to jump to upon completion */ __enable_mmu: #ifdef CONFIG_ALIGNMENT_TRAP @@ -335,6 +342,9 @@ ENDPROC(__enable_mmu) * mailing list archives BEFORE sending another post to the list. * * r0 = cp#15 control register + * r1 = machine ID + * r2 = atags pointer + * r9 = processor ID * r13 = *virtual* address to jump to upon completion * * other registers depend on the function called upon completion -- cgit