From 62118b7b0183d29755a101a6a5b88dee11c5f94b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Mon, 23 Mar 2015 00:07:31 +0900 Subject: [PATCH] ARM: UniPhier: optimize kicking secondary CPUs code Currently, the secondary CPU(s) are kicked three times: Boot ROM ---(kick)--> SPL ---(kick)--> U-boot ---(kick)--> Linux. It makes the boot sequence very complicated. This commit merges the first and the second kicks, so the secondary CPU(s) can directly jump from SPL to Linux. arch/arm/mach-uniphier/smp.S is no longer necessary. Linux boot test passed. Signed-off-by: Masahiro Yamada --- arch/arm/mach-uniphier/Makefile | 1 - arch/arm/mach-uniphier/cache_uniphier.c | 13 +----- arch/arm/mach-uniphier/lowlevel_init.S | 42 ++++++++++++++++--- arch/arm/mach-uniphier/smp.S | 54 ------------------------- 4 files changed, 38 insertions(+), 72 deletions(-) delete mode 100644 arch/arm/mach-uniphier/smp.S diff --git a/arch/arm/mach-uniphier/Makefile b/arch/arm/mach-uniphier/Makefile index f191aa3d76..24591d6ee5 100644 --- a/arch/arm/mach-uniphier/Makefile +++ b/arch/arm/mach-uniphier/Makefile @@ -22,7 +22,6 @@ obj-$(CONFIG_BOARD_EARLY_INIT_R) += board_early_init_r.o obj-$(CONFIG_BOARD_LATE_INIT) += board_late_init.o obj-y += reset.o obj-y += cache_uniphier.o -obj-$(CONFIG_UNIPHIER_SMP) += smp.o obj-$(CONFIG_CMD_PINMON) += cmd_pinmon.o obj-$(CONFIG_CMD_DDRPHY_DUMP) += cmd_ddrphy.o diff --git a/arch/arm/mach-uniphier/cache_uniphier.c b/arch/arm/mach-uniphier/cache_uniphier.c index 52f3c7c7a6..4bf01bce3e 100644 --- a/arch/arm/mach-uniphier/cache_uniphier.c +++ b/arch/arm/mach-uniphier/cache_uniphier.c @@ -1,6 +1,7 @@ /* * Copyright (C) 2012-2014 Panasonic Corporation - * Author: Masahiro Yamada + * Copyright (C) 2015 Socionext Inc. + * Author: Masahiro Yamada * * SPDX-License-Identifier: GPL-2.0+ */ @@ -119,20 +120,10 @@ void v7_outer_cache_disable(void) writel(tmp, SSCC); } -void wakeup_secondary(void); - void enable_caches(void) { uint32_t reg; -#ifdef CONFIG_UNIPHIER_SMP - /* - * The secondary CPU must move to DDR, - * before L2 disable. - * On SPL, the Page Table is located on the L2. - */ - wakeup_secondary(); -#endif /* * UniPhier SoCs must use L2 cache for init stack pointer. * We disable L2 and L1 in this order. diff --git a/arch/arm/mach-uniphier/lowlevel_init.S b/arch/arm/mach-uniphier/lowlevel_init.S index 4a23ea4d56..825b160762 100644 --- a/arch/arm/mach-uniphier/lowlevel_init.S +++ b/arch/arm/mach-uniphier/lowlevel_init.S @@ -48,6 +48,25 @@ ENTRY(lowlevel_init) bl enable_mmu #ifdef CONFIG_UNIPHIER_SMP +secondary_startup: + /* + * Entry point for secondary CPUs + * + * The Boot ROM has already enabled MMU for the secondary CPUs as well + * as for the primary one. The MMU table embedded in the Boot ROM + * prohibits the DRAM access, so it is impossible to bring the + * secondary CPUs into DRAM directly. They must jump here into SPL, + * which is run on L2 cache. + * + * Boot Sequence + * [primary CPU] [secondary CPUs] + * start from Boot ROM start from Boot ROM + * jump to SPL sleep in Boot ROM + * kick secondaries ---(sev)---> jump to SPL + * jump to U-Boot main sleep in SPL + * jump to Linux + * kick secondaries ---(sev)---> jump to Linux + */ /* * ACTLR (Auxiliary Control Register) for Cortex-A9 * bit[9] Parity on @@ -68,17 +87,28 @@ ENTRY(lowlevel_init) and r0, r0, #0x3 cmp r0, #0x0 beq primary_cpu - ldr r1, =ROM_BOOT_ROMRSV2 + /* only for secondary CPUs */ + ldr r1, =ROM_BOOT_ROMRSV2 @ The last data access to L2 cache + mrc p15, 0, r0, c1, c0, 0 @ SCTLR (System Control Register) + orr r0, r0, #CR_I @ Enable ICache + bic r0, r0, #(CR_C | CR_M) @ MMU and Dcache must be disabled + mcr p15, 0, r0, c1, c0, 0 @ before jumping to Linux mov r0, #0 str r0, [r1] -0: wfe - ldr r0, [r1] + b 1f + /* + * L2 cache is shared among all the CPUs and it might be disabled by + * the primary one. Before that, the following 5 lines must be cached + * on the Icaches of the secondary CPUs. + */ +0: wfe @ kicked by Linux +1: ldr r0, [r1] cmp r0, #0 - beq 0b - bx r0 @ r0: entry point of U-Boot main for the secondary CPU + bxne r0 @ r0: Linux entry for secondary CPUs + b 0b primary_cpu: ldr r1, =ROM_BOOT_ROMRSV2 - ldr r0, =_start @ entry for the secondary CPU + ldr r0, =secondary_startup str r0, [r1] ldr r0, [r1] @ make sure str is complete before sev sev @ kick the secondary CPU diff --git a/arch/arm/mach-uniphier/smp.S b/arch/arm/mach-uniphier/smp.S deleted file mode 100644 index 18e3a9d21e..0000000000 --- a/arch/arm/mach-uniphier/smp.S +++ /dev/null @@ -1,54 +0,0 @@ -/* - * Copyright (C) 2013 Panasonic Corporation - * Author: Masahiro Yamada - * - * SPDX-License-Identifier: GPL-2.0+ - */ - -#include -#include -#include -#include -#include - -/* Entry point of U-Boot main program for the secondary CPU */ -LENTRY(secondary_entry) - mrc p15, 0, r0, c1, c0, 0 @ SCTLR (System Contrl Register) - bic r0, r0, #(CR_C | CR_M) @ MMU and Dcache disable - mcr p15, 0, r0, c1, c0, 0 - mcr p15, 0, r0, c8, c7, 0 @ invalidate TLBs - mcr p15, 0, r0, c7, c5, 0 @ invalidate icache - dsb - led_write(C,0,,) - ldr r1, =ROM_BOOT_ROMRSV2 - mov r0, #0 - str r0, [r1] -0: wfe - ldr r4, [r1] @ r4: entry point for secondary CPUs - cmp r4, #0 - beq 0b - led_write(C, P, U, 1) - bx r4 @ secondary CPUs jump to linux -ENDPROC(secondary_entry) - -ENTRY(wakeup_secondary) - ldr r1, =ROM_BOOT_ROMRSV2 -0: ldr r0, [r1] - cmp r0, #0 - bne 0b - - /* set entry address and send event to the secondary CPU */ - ldr r0, =secondary_entry - str r0, [r1] - ldr r0, [r1] @ make sure store is complete - mov r0, #0x100 -0: subs r0, r0, #1 @ I don't know the reason, but without this wait - bne 0b @ fails to wake up the secondary CPU - sev - - /* wait until the secondary CPU reach to secondary_entry */ -0: ldr r0, [r1] - cmp r0, #0 - bne 0b - bx lr -ENDPROC(wakeup_secondary) -- 2.39.5