From dcd468b8f43c5077c42c75b15cf3204e6b6be46c Mon Sep 17 00:00:00 2001 From: York Sun Date: Tue, 6 Jan 2015 13:18:42 -0800 Subject: armv8/fsl-lsch3: Convert flushing L3 to assembly to avoid using stack Flushing L3 cache in CCN-504 requries d-cache to be disabled. Using assembly function to guarantee stack is not used before flushing is completed. Timeout is needed for simualtor on which CCN-504 is not implemented. Return value can be checked for timeout situation. Change bootm.c to disable dcache instead of simply flushing, required by flushing L3. Signed-off-by: York Sun --- arch/arm/cpu/armv8/fsl-lsch3/cpu.c | 53 ---------------------- arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S | 78 +++++++++++++++++++++++++++++++++ 2 files changed, 78 insertions(+), 53 deletions(-) (limited to 'arch/arm/cpu/armv8/fsl-lsch3') diff --git a/arch/arm/cpu/armv8/fsl-lsch3/cpu.c b/arch/arm/cpu/armv8/fsl-lsch3/cpu.c index ada1690ed9..2aaac017d2 100644 --- a/arch/arm/cpu/armv8/fsl-lsch3/cpu.c +++ b/arch/arm/cpu/armv8/fsl-lsch3/cpu.c @@ -242,59 +242,6 @@ int arch_cpu_init(void) return 0; } -/* - * flush_l3_cache - * Dickens L3 cache can be flushed by transitioning from FAM to SFONLY power - * state, by writing to HP-F P-state request register. - * Fixme: This function should moved to a common file if other SoCs also use - * the same Dickens. - */ -#define HNF0_PSTATE_REQ 0x04200010 -#define HNF1_PSTATE_REQ 0x04210010 -#define HNF2_PSTATE_REQ 0x04220010 -#define HNF3_PSTATE_REQ 0x04230010 -#define HNF4_PSTATE_REQ 0x04240010 -#define HNF5_PSTATE_REQ 0x04250010 -#define HNF6_PSTATE_REQ 0x04260010 -#define HNF7_PSTATE_REQ 0x04270010 -#define HNFPSTAT_MASK (0xFFFFFFFFFFFFFFFC) -#define HNFPSTAT_FAM 0x3 -#define HNFPSTAT_SFONLY 0x01 - -static void hnf_pstate_req(u64 *ptr, u64 state) -{ - int timeout = 1000; - out_le64(ptr, (in_le64(ptr) & HNFPSTAT_MASK) | (state & 0x3)); - ptr++; - /* checking if the transition is completed */ - while (timeout > 0) { - if (((in_le64(ptr) & 0x0c) >> 2) == (state & 0x3)) - break; - udelay(100); - timeout--; - } -} - -void flush_l3_cache(void) -{ - hnf_pstate_req((u64 *)HNF0_PSTATE_REQ, HNFPSTAT_SFONLY); - hnf_pstate_req((u64 *)HNF1_PSTATE_REQ, HNFPSTAT_SFONLY); - hnf_pstate_req((u64 *)HNF2_PSTATE_REQ, HNFPSTAT_SFONLY); - hnf_pstate_req((u64 *)HNF3_PSTATE_REQ, HNFPSTAT_SFONLY); - hnf_pstate_req((u64 *)HNF4_PSTATE_REQ, HNFPSTAT_SFONLY); - hnf_pstate_req((u64 *)HNF5_PSTATE_REQ, HNFPSTAT_SFONLY); - hnf_pstate_req((u64 *)HNF6_PSTATE_REQ, HNFPSTAT_SFONLY); - hnf_pstate_req((u64 *)HNF7_PSTATE_REQ, HNFPSTAT_SFONLY); - hnf_pstate_req((u64 *)HNF0_PSTATE_REQ, HNFPSTAT_FAM); - hnf_pstate_req((u64 *)HNF1_PSTATE_REQ, HNFPSTAT_FAM); - hnf_pstate_req((u64 *)HNF2_PSTATE_REQ, HNFPSTAT_FAM); - hnf_pstate_req((u64 *)HNF3_PSTATE_REQ, HNFPSTAT_FAM); - hnf_pstate_req((u64 *)HNF4_PSTATE_REQ, HNFPSTAT_FAM); - hnf_pstate_req((u64 *)HNF5_PSTATE_REQ, HNFPSTAT_FAM); - hnf_pstate_req((u64 *)HNF6_PSTATE_REQ, HNFPSTAT_FAM); - hnf_pstate_req((u64 *)HNF7_PSTATE_REQ, HNFPSTAT_FAM); -} - /* * This function is called from lib/board.c. * It recreates MMU table in main memory. MMU and d-cache are enabled earlier. diff --git a/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S b/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S index c2837876b1..886576ef99 100644 --- a/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S +++ b/arch/arm/cpu/armv8/fsl-lsch3/lowlevel.S @@ -100,6 +100,84 @@ ENTRY(lowlevel_init) ret ENDPROC(lowlevel_init) +hnf_pstate_poll: + /* x0 has the desired status, return 0 for success, 1 for timeout + * clobber x1, x2, x3, x4, x6, x7 + */ + mov x1, x0 + mov x7, #0 /* flag for timeout */ + mrs x3, cntpct_el0 /* read timer */ + add x3, x3, #1200 /* timeout after 100 microseconds */ + mov x0, #0x18 + movk x0, #0x420, lsl #16 /* HNF0_PSTATE_STATUS */ + mov w6, #8 /* HN-F node count */ +1: + ldr x2, [x0] + cmp x2, x1 /* check status */ + b.eq 2f + mrs x4, cntpct_el0 + cmp x4, x3 + b.ls 1b + mov x7, #1 /* timeout */ + b 3f +2: + add x0, x0, #0x10000 /* move to next node */ + subs w6, w6, #1 + cbnz w6, 1b +3: + mov x0, x7 + ret + +hnf_set_pstate: + /* x0 has the desired state, clobber x1, x2, x6 */ + mov x1, x0 + /* power state to SFONLY */ + mov w6, #8 /* HN-F node count */ + mov x0, #0x10 + movk x0, #0x420, lsl #16 /* HNF0_PSTATE_REQ */ +1: /* set pstate to sfonly */ + ldr x2, [x0] + and x2, x2, #0xfffffffffffffffc /* & HNFPSTAT_MASK */ + orr x2, x2, x1 + str x2, [x0] + add x0, x0, #0x10000 /* move to next node */ + subs w6, w6, #1 + cbnz w6, 1b + + ret + +ENTRY(__asm_flush_l3_cache) + /* + * Return status in x0 + * success 0 + * tmeout 1 for setting SFONLY, 2 for FAM, 3 for both + */ + mov x29, lr + mov x8, #0 + + dsb sy + mov x0, #0x1 /* HNFPSTAT_SFONLY */ + bl hnf_set_pstate + + mov x0, #0x4 /* SFONLY status */ + bl hnf_pstate_poll + cbz x0, 1f + mov x8, #1 /* timeout */ +1: + dsb sy + mov x0, #0x3 /* HNFPSTAT_FAM */ + bl hnf_set_pstate + + mov x0, #0xc /* FAM status */ + bl hnf_pstate_poll + cbz x0, 1f + add x8, x8, #0x2 +1: + mov x0, x8 + mov lr, x29 + ret +ENDPROC(__asm_flush_l3_cache) + /* Keep literals not used by the secondary boot code outside it */ .ltorg -- cgit v1.2.1