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authorLinus Torvalds <torvalds@linux-foundation.org>2013-07-03 09:46:29 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-07-03 09:46:29 -0700
commitfb2af0020a51709ad87ea8055c325d3fbde04158 (patch)
tree88f3bc38d5604c6eed00597873f209726f9aaeb5 /arch/arm/kernel/sleep.S
parent790eac5640abf7a57fa3a644386df330e18c11b0 (diff)
parent3c0c01ab742ddfaf6b6f2d64b890e77cda4b7727 (diff)
Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull ARM updates from Russell King: "This contains the usual updates from other people (listed below) and the usual random muddle of miscellaneous ARM updates which cover some low priority bug fixes and performance improvements. I've started to put the pull request wording into the merge commits, which are: - NoMMU stuff: This includes the following series sent earlier to the list: - nommu-fixes - R7 Support - MPU support I've left out the ARCH_MULTIPLATFORM/!MMU stuff that Arnd and I were discussing today until we've reached a conclusion/that's had some more review. This is rebased (and re-tested) on your devel-stable branch because otherwise there were going to be conflicts with Uwe's V7M work now that you've merged that. I've included the fix for limiting MPU to CPU_V7. - Huge page support These changes bring both HugeTLB support and Transparent HugePage (THP) support to ARM. Only long descriptors (LPAE) are supported in this series. The code has been tested on an Arndale board (Exynos 5250). - LPAE updates Please pull these miscellaneous LPAE fixes I've been collecting for a while now for 3.11. They've been tested and reviewed by quite a few people, and most of the patches are pretty trivial. -- Will Deacon. - arch_timer cleanups Please pull these arch_timer cleanups I've been holding onto for a while. They're the same as my last posting, but have been rebased to v3.10-rc3. - mpidr linearisation (multiprocessor id register - identifies which CPU number we are in the system) This patch series that implements MPIDR linearization through a simple hashing algorithm and updates current cpu_{suspend}/{resume} code to use the newly created hash structures to retrieve context pointers. It represents a stepping stone for the implementation of power management code on forthcoming multi-cluster ARM systems. It has been tested on TC2 (dual cluster A15xA7 system), iMX6q, OMAP4 and Tegra, with processors hitting low-power states requiring warm-boot resume through the cpu_resume code path" * 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (77 commits) ARM: 7775/1: mm: Remove do_sect_fault from LPAE code ARM: 7777/1: Avoid extra calls to the C compiler ARM: 7774/1: Fix dtb dependency to use order-only prerequisites ARM: 7770/1: remove residual ARMv2 support from decompressor ARM: 7769/1: Cortex-A15: fix erratum 798181 implementation ARM: 7768/1: prevent risks of out-of-bound access in ASID allocator ARM: 7767/1: let the ASID allocator handle suspended animation ARM: 7766/1: versatile: don't mark pen as __INIT ARM: 7765/1: perf: Record the user-mode PC in the call chain. ARM: 7735/2: Preserve the user r/w register TPIDRURW on context switch and fork ARM: kernel: implement stack pointer save array through MPIDR hashing ARM: kernel: build MPIDR hash function data structure ARM: mpu: Ensure that MPU depends on CPU_V7 ARM: mpu: protect the vectors page with an MPU region ARM: mpu: Allow enabling of the MPU via kconfig ARM: 7758/1: introduce config HAS_BANDGAP ARM: 7757/1: mm: don't flush icache in switch_mm with hardware broadcasting ARM: 7751/1: zImage: don't overwrite ourself with a page table ARM: 7749/1: spinlock: retry trylock operation if strex fails on free lock ARM: 7748/1: oabi: handle faults when loading swi instruction from userspace ...
Diffstat (limited to 'arch/arm/kernel/sleep.S')
-rw-r--r--arch/arm/kernel/sleep.S97
1 files changed, 79 insertions, 18 deletions
diff --git a/arch/arm/kernel/sleep.S b/arch/arm/kernel/sleep.S
index 987dcf33415c..db1536b8b30b 100644
--- a/arch/arm/kernel/sleep.S
+++ b/arch/arm/kernel/sleep.S
@@ -7,6 +7,49 @@
.text
/*
+ * Implementation of MPIDR hash algorithm through shifting
+ * and OR'ing.
+ *
+ * @dst: register containing hash result
+ * @rs0: register containing affinity level 0 bit shift
+ * @rs1: register containing affinity level 1 bit shift
+ * @rs2: register containing affinity level 2 bit shift
+ * @mpidr: register containing MPIDR value
+ * @mask: register containing MPIDR mask
+ *
+ * Pseudo C-code:
+ *
+ *u32 dst;
+ *
+ *compute_mpidr_hash(u32 rs0, u32 rs1, u32 rs2, u32 mpidr, u32 mask) {
+ * u32 aff0, aff1, aff2;
+ * u32 mpidr_masked = mpidr & mask;
+ * aff0 = mpidr_masked & 0xff;
+ * aff1 = mpidr_masked & 0xff00;
+ * aff2 = mpidr_masked & 0xff0000;
+ * dst = (aff0 >> rs0 | aff1 >> rs1 | aff2 >> rs2);
+ *}
+ * Input registers: rs0, rs1, rs2, mpidr, mask
+ * Output register: dst
+ * Note: input and output registers must be disjoint register sets
+ (eg: a macro instance with mpidr = r1 and dst = r1 is invalid)
+ */
+ .macro compute_mpidr_hash dst, rs0, rs1, rs2, mpidr, mask
+ and \mpidr, \mpidr, \mask @ mask out MPIDR bits
+ and \dst, \mpidr, #0xff @ mask=aff0
+ ARM( mov \dst, \dst, lsr \rs0 ) @ dst=aff0>>rs0
+ THUMB( lsr \dst, \dst, \rs0 )
+ and \mask, \mpidr, #0xff00 @ mask = aff1
+ ARM( orr \dst, \dst, \mask, lsr \rs1 ) @ dst|=(aff1>>rs1)
+ THUMB( lsr \mask, \mask, \rs1 )
+ THUMB( orr \dst, \dst, \mask )
+ and \mask, \mpidr, #0xff0000 @ mask = aff2
+ ARM( orr \dst, \dst, \mask, lsr \rs2 ) @ dst|=(aff2>>rs2)
+ THUMB( lsr \mask, \mask, \rs2 )
+ THUMB( orr \dst, \dst, \mask )
+ .endm
+
+/*
* Save CPU state for a suspend. This saves the CPU general purpose
* registers, and allocates space on the kernel stack to save the CPU
* specific registers and some other data for resume.
@@ -29,12 +72,18 @@ ENTRY(__cpu_suspend)
mov r1, r4 @ size of save block
mov r2, r5 @ virtual SP
ldr r3, =sleep_save_sp
-#ifdef CONFIG_SMP
- ALT_SMP(mrc p15, 0, lr, c0, c0, 5)
- ALT_UP(mov lr, #0)
- and lr, lr, #15
+ ldr r3, [r3, #SLEEP_SAVE_SP_VIRT]
+ ALT_SMP(mrc p15, 0, r9, c0, c0, 5)
+ ALT_UP_B(1f)
+ ldr r8, =mpidr_hash
+ /*
+ * This ldmia relies on the memory layout of the mpidr_hash
+ * struct mpidr_hash.
+ */
+ ldmia r8, {r4-r7} @ r4 = mpidr mask (r5,r6,r7) = l[0,1,2] shifts
+ compute_mpidr_hash lr, r5, r6, r7, r9, r4
add r3, r3, lr, lsl #2
-#endif
+1:
bl __cpu_suspend_save
adr lr, BSYM(cpu_suspend_abort)
ldmfd sp!, {r0, pc} @ call suspend fn
@@ -81,15 +130,23 @@ ENDPROC(cpu_resume_after_mmu)
.data
.align
ENTRY(cpu_resume)
-#ifdef CONFIG_SMP
- adr r0, sleep_save_sp
- ALT_SMP(mrc p15, 0, r1, c0, c0, 5)
- ALT_UP(mov r1, #0)
- and r1, r1, #15
- ldr r0, [r0, r1, lsl #2] @ stack phys addr
-#else
- ldr r0, sleep_save_sp @ stack phys addr
-#endif
+ mov r1, #0
+ ALT_SMP(mrc p15, 0, r0, c0, c0, 5)
+ ALT_UP_B(1f)
+ adr r2, mpidr_hash_ptr
+ ldr r3, [r2]
+ add r2, r2, r3 @ r2 = struct mpidr_hash phys address
+ /*
+ * This ldmia relies on the memory layout of the mpidr_hash
+ * struct mpidr_hash.
+ */
+ ldmia r2, { r3-r6 } @ r3 = mpidr mask (r4,r5,r6) = l[0,1,2] shifts
+ compute_mpidr_hash r1, r4, r5, r6, r0, r3
+1:
+ adr r0, _sleep_save_sp
+ ldr r0, [r0, #SLEEP_SAVE_SP_PHYS]
+ ldr r0, [r0, r1, lsl #2]
+
setmode PSR_I_BIT | PSR_F_BIT | SVC_MODE, r1 @ set SVC, irqs off
@ load phys pgd, stack, resume fn
ARM( ldmia r0!, {r1, sp, pc} )
@@ -98,7 +155,11 @@ THUMB( mov sp, r2 )
THUMB( bx r3 )
ENDPROC(cpu_resume)
-sleep_save_sp:
- .rept CONFIG_NR_CPUS
- .long 0 @ preserve stack phys ptr here
- .endr
+ .align 2
+mpidr_hash_ptr:
+ .long mpidr_hash - . @ mpidr_hash struct offset
+
+ .type sleep_save_sp, #object
+ENTRY(sleep_save_sp)
+_sleep_save_sp:
+ .space SLEEP_SAVE_SP_SZ @ struct sleep_save_sp