/* SPDX-License-Identifier: GPL-2.0 */#include <linux/errno.h>#include <linux/linkage.h>#include <asm/asm-offsets.h>#include <asm/assembler.h>#include <asm/smp.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; *	aff3 = 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 */SYM_FUNC_START(__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_l	x1, sleep_save_stash	mrs	x7, mpidr_el1	adr_l	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	retSYM_FUNC_END(__cpu_suspend_enter) 	.pushsection ".idmap.text", "a"SYM_CODE_START(cpu_resume)	mov	x0, xzr	bl	init_kernel_el	mov	x19, x0			// preserve boot mode	bl	__cpu_setup	/* enable the MMU early - so we can access sleep_save_stash by va */	adrp	x1, swapper_pg_dir	adrp	x2, idmap_pg_dir	bl	__enable_mmu	ldr	x8, =_cpu_resume	br	x8SYM_CODE_END(cpu_resume)	.ltorg	.popsection SYM_FUNC_START(_cpu_resume)	mov	x0, x19	bl	finalise_el2 	mrs	x1, mpidr_el1	adr_l	x8, mpidr_hash		// x8 = struct mpidr_hash virt 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	/*	 * cpu_do_resume expects x0 to contain context address pointer	 */	bl	cpu_do_resume #if defined(CONFIG_KASAN) && defined(CONFIG_KASAN_STACK)	mov	x0, sp	bl	kasan_unpoison_task_stack_below#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	retSYM_FUNC_END(_cpu_resume)