| #include <linux/errno.h> |
| #include <linux/linkage.h> |
| #include <asm/asm-offsets.h> |
| #include <asm/assembler.h> |
| |
| .text |
| /* |
| * Implementation of MPIDR_EL1 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 |
| * @rs3: register containing affinity level 3 bit shift |
| * @mpidr: register containing MPIDR_EL1 value |
| * @mask: register containing MPIDR mask |
| * |
| * Pseudo C-code: |
| * |
| *u32 dst; |
| * |
| *compute_mpidr_hash(u32 rs0, u32 rs1, u32 rs2, u32 rs3, u64 mpidr, u64 mask) { |
| * u32 aff0, aff1, aff2, aff3; |
| * u64 mpidr_masked = mpidr & mask; |
| * aff0 = mpidr_masked & 0xff; |
| * aff1 = mpidr_masked & 0xff00; |
| * aff2 = mpidr_masked & 0xff0000; |
| * aff2 = mpidr_masked & 0xff00000000; |
| * dst = (aff0 >> rs0 | aff1 >> rs1 | aff2 >> rs2 | aff3 >> rs3); |
| *} |
| * Input registers: rs0, rs1, rs2, rs3, mpidr, mask |
| * Output register: dst |
| * Note: input and output registers must be disjoint register sets |
| (eg: a macro instance with mpidr = x1 and dst = x1 is invalid) |
| */ |
| .macro compute_mpidr_hash dst, rs0, rs1, rs2, rs3, mpidr, mask |
| and \mpidr, \mpidr, \mask // mask out MPIDR bits |
| and \dst, \mpidr, #0xff // mask=aff0 |
| lsr \dst ,\dst, \rs0 // dst=aff0>>rs0 |
| and \mask, \mpidr, #0xff00 // mask = aff1 |
| lsr \mask ,\mask, \rs1 |
| orr \dst, \dst, \mask // dst|=(aff1>>rs1) |
| and \mask, \mpidr, #0xff0000 // mask = aff2 |
| lsr \mask ,\mask, \rs2 |
| orr \dst, \dst, \mask // dst|=(aff2>>rs2) |
| and \mask, \mpidr, #0xff00000000 // mask = aff3 |
| lsr \mask ,\mask, \rs3 |
| orr \dst, \dst, \mask // dst|=(aff3>>rs3) |
| .endm |
| /* |
| * Save CPU state in the provided sleep_stack_data area, and publish its |
| * location for cpu_resume()'s use in sleep_save_stash. |
| * |
| * cpu_resume() will restore this saved state, and return. Because the |
| * link-register is saved and restored, it will appear to return from this |
| * function. So that the caller can tell the suspend/resume paths apart, |
| * __cpu_suspend_enter() will always return a non-zero value, whereas the |
| * path through cpu_resume() will return 0. |
| * |
| * x0 = struct sleep_stack_data area |
| */ |
| ENTRY(__cpu_suspend_enter) |
| stp x29, lr, [x0, #SLEEP_STACK_DATA_CALLEE_REGS] |
| stp x19, x20, [x0,#SLEEP_STACK_DATA_CALLEE_REGS+16] |
| stp x21, x22, [x0,#SLEEP_STACK_DATA_CALLEE_REGS+32] |
| stp x23, x24, [x0,#SLEEP_STACK_DATA_CALLEE_REGS+48] |
| stp x25, x26, [x0,#SLEEP_STACK_DATA_CALLEE_REGS+64] |
| stp x27, x28, [x0,#SLEEP_STACK_DATA_CALLEE_REGS+80] |
| |
| /* save the sp in cpu_suspend_ctx */ |
| mov x2, sp |
| str x2, [x0, #SLEEP_STACK_DATA_SYSTEM_REGS + CPU_CTX_SP] |
| |
| /* find the mpidr_hash */ |
| ldr x1, =sleep_save_stash |
| ldr x1, [x1] |
| mrs x7, mpidr_el1 |
| ldr x9, =mpidr_hash |
| ldr x10, [x9, #MPIDR_HASH_MASK] |
| /* |
| * Following code relies on the struct mpidr_hash |
| * members size. |
| */ |
| ldp w3, w4, [x9, #MPIDR_HASH_SHIFTS] |
| ldp w5, w6, [x9, #(MPIDR_HASH_SHIFTS + 8)] |
| compute_mpidr_hash x8, x3, x4, x5, x6, x7, x10 |
| add x1, x1, x8, lsl #3 |
| |
| str x0, [x1] |
| add x0, x0, #SLEEP_STACK_DATA_SYSTEM_REGS |
| stp x29, lr, [sp, #-16]! |
| bl cpu_do_suspend |
| ldp x29, lr, [sp], #16 |
| mov x0, #1 |
| ret |
| ENDPROC(__cpu_suspend_enter) |
| .ltorg |
| |
| ENTRY(cpu_resume) |
| bl el2_setup // if in EL2 drop to EL1 cleanly |
| /* enable the MMU early - so we can access sleep_save_stash by va */ |
| adr_l lr, __enable_mmu /* __cpu_setup will return here */ |
| ldr x27, =_cpu_resume /* __enable_mmu will branch here */ |
| adrp x25, idmap_pg_dir |
| adrp x26, swapper_pg_dir |
| b __cpu_setup |
| ENDPROC(cpu_resume) |
| |
| ENTRY(_cpu_resume) |
| mrs x1, mpidr_el1 |
| adrp x8, mpidr_hash |
| add x8, x8, #:lo12:mpidr_hash // x8 = struct mpidr_hash phys address |
| /* retrieve mpidr_hash members to compute the hash */ |
| ldr x2, [x8, #MPIDR_HASH_MASK] |
| ldp w3, w4, [x8, #MPIDR_HASH_SHIFTS] |
| ldp w5, w6, [x8, #(MPIDR_HASH_SHIFTS + 8)] |
| compute_mpidr_hash x7, x3, x4, x5, x6, x1, x2 |
| /* x7 contains hash index, let's use it to grab context pointer */ |
| ldr_l x0, sleep_save_stash |
| ldr x0, [x0, x7, lsl #3] |
| add x29, x0, #SLEEP_STACK_DATA_CALLEE_REGS |
| add x0, x0, #SLEEP_STACK_DATA_SYSTEM_REGS |
| /* load sp from context */ |
| ldr x2, [x0, #CPU_CTX_SP] |
| mov sp, x2 |
| /* save thread_info */ |
| and x2, x2, #~(THREAD_SIZE - 1) |
| msr sp_el0, x2 |
| /* |
| * cpu_do_resume expects x0 to contain context address pointer |
| */ |
| bl cpu_do_resume |
| |
| #ifdef CONFIG_KASAN |
| mov x0, sp |
| bl kasan_unpoison_remaining_stack |
| #endif |
| |
| ldp x19, x20, [x29, #16] |
| ldp x21, x22, [x29, #32] |
| ldp x23, x24, [x29, #48] |
| ldp x25, x26, [x29, #64] |
| ldp x27, x28, [x29, #80] |
| ldp x29, lr, [x29] |
| mov x0, #0 |
| ret |
| ENDPROC(_cpu_resume) |