ARM: v7 setup function should invalidate L1 cache
authorRussell King <rmk+kernel@arm.linux.org.uk>
Tue, 19 May 2015 16:06:44 +0000 (17:06 +0100)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Mon, 1 Jun 2015 10:30:26 +0000 (11:30 +0100)
All ARMv5 and older CPUs invalidate their caches in the early assembly
setup function, prior to enabling the MMU.  This is because the L1
cache should not contain any data relevant to the execution of the
kernel at this point; all data should have been flushed out to memory.

This requirement should also be true for ARMv6 and ARMv7 CPUs - indeed,
these typically do not search their caches when caching is disabled (as
it needs to be when the MMU is disabled) so this change should be safe.

ARMv7 allows there to be CPUs which search their caches while caching is
disabled, and it's permitted that the cache is uninitialised at boot;
for these, the architecture reference manual requires that an
implementation specific code sequence is used immediately after reset
to ensure that the cache is placed into a sane state.  Such
functionality is definitely outside the remit of the Linux kernel, and
must be done by the SoC's firmware before _any_ CPU gets to the Linux
kernel.

Changing the data cache clean+invalidate to a mere invalidate allows us
to get rid of a lot of platform specific hacks around this issue for
their secondary CPU bringup paths - some of which were buggy.

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Dinh Nguyen <dinguyen@opensource.altera.com>
Acked-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Thierry Reding <treding@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
31 files changed:
arch/arm/mach-bcm/Makefile
arch/arm/mach-bcm/brcmstb.h [deleted file]
arch/arm/mach-bcm/headsmp-brcmstb.S [deleted file]
arch/arm/mach-bcm/platsmp-brcmstb.c
arch/arm/mach-berlin/headsmp.S
arch/arm/mach-berlin/platsmp.c
arch/arm/mach-hisi/Makefile
arch/arm/mach-hisi/core.h
arch/arm/mach-hisi/headsmp.S [deleted file]
arch/arm/mach-hisi/platsmp.c
arch/arm/mach-imx/headsmp.S
arch/arm/mach-mvebu/headsmp-a9.S
arch/arm/mach-prima2/headsmp.S
arch/arm/mach-rockchip/core.h
arch/arm/mach-rockchip/headsmp.S
arch/arm/mach-rockchip/platsmp.c
arch/arm/mach-shmobile/common.h
arch/arm/mach-shmobile/headsmp-scu.S
arch/arm/mach-shmobile/headsmp.S
arch/arm/mach-shmobile/platsmp-apmu.c
arch/arm/mach-socfpga/core.h
arch/arm/mach-socfpga/headsmp.S
arch/arm/mach-socfpga/platsmp.c
arch/arm/mach-tegra/Makefile
arch/arm/mach-tegra/headsmp.S [deleted file]
arch/arm/mach-tegra/reset.c
arch/arm/mach-tegra/reset.h
arch/arm/mach-zynq/common.h
arch/arm/mach-zynq/headsmp.S
arch/arm/mach-zynq/platsmp.c
arch/arm/mm/proc-v7.S

index 4c38674..54d274d 100644 (file)
@@ -43,5 +43,5 @@ obj-$(CONFIG_ARCH_BCM_63XX)   := bcm63xx.o
 ifeq ($(CONFIG_ARCH_BRCMSTB),y)
 CFLAGS_platsmp-brcmstb.o       += -march=armv7-a
 obj-y                          += brcmstb.o
-obj-$(CONFIG_SMP)              += headsmp-brcmstb.o platsmp-brcmstb.o
+obj-$(CONFIG_SMP)              += platsmp-brcmstb.o
 endif
diff --git a/arch/arm/mach-bcm/brcmstb.h b/arch/arm/mach-bcm/brcmstb.h
deleted file mode 100644 (file)
index ec0c3d1..0000000
+++ /dev/null
@@ -1,19 +0,0 @@
-/*
- * Copyright (C) 2013-2014 Broadcom Corporation
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation version 2.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any
- * kind, whether express or implied; without even the implied warranty
- * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#ifndef __BRCMSTB_H__
-#define __BRCMSTB_H__
-
-void brcmstb_secondary_startup(void);
-
-#endif /* __BRCMSTB_H__ */
diff --git a/arch/arm/mach-bcm/headsmp-brcmstb.S b/arch/arm/mach-bcm/headsmp-brcmstb.S
deleted file mode 100644 (file)
index 199c1ea..0000000
+++ /dev/null
@@ -1,33 +0,0 @@
-/*
- * SMP boot code for secondary CPUs
- * Based on arch/arm/mach-tegra/headsmp.S
- *
- * Copyright (C) 2010 NVIDIA, Inc.
- * Copyright (C) 2013-2014 Broadcom Corporation
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation version 2.
- *
- * This program is distributed "as is" WITHOUT ANY WARRANTY of any
- * kind, whether express or implied; without even the implied warranty
- * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#include <asm/assembler.h>
-#include <linux/linkage.h>
-#include <linux/init.h>
-
-        .section ".text.head", "ax"
-
-ENTRY(brcmstb_secondary_startup)
-        /*
-         * Ensure CPU is in a sane state by disabling all IRQs and switching
-         * into SVC mode.
-         */
-        setmode        PSR_I_BIT | PSR_F_BIT | SVC_MODE, r0
-
-        bl      v7_invalidate_l1
-        b       secondary_startup
-ENDPROC(brcmstb_secondary_startup)
index e209e6f..44d6bdd 100644 (file)
@@ -30,8 +30,6 @@
 #include <asm/mach-types.h>
 #include <asm/smp_plat.h>
 
-#include "brcmstb.h"
-
 enum {
        ZONE_MAN_CLKEN_MASK             = BIT(0),
        ZONE_MAN_RESET_CNTL_MASK        = BIT(1),
@@ -153,7 +151,7 @@ static void brcmstb_cpu_boot(u32 cpu)
         * Set the reset vector to point to the secondary_startup
         * routine
         */
-       cpu_set_boot_addr(cpu, virt_to_phys(brcmstb_secondary_startup));
+       cpu_set_boot_addr(cpu, virt_to_phys(secondary_startup));
 
        /* Unhalt the cpu */
        cpu_rst_cfg_set(cpu, 0);
index 4a4c56a..dc82a34 100644 (file)
 #include <linux/init.h>
 #include <asm/assembler.h>
 
-ENTRY(berlin_secondary_startup)
- ARM_BE8(setend be)
-       bl      v7_invalidate_l1
-       b       secondary_startup
-ENDPROC(berlin_secondary_startup)
-
 /*
  * If the following instruction is set in the reset exception vector, CPUs
  * will fetch the value of the software reset address vector when being
index 702e798..34a3753 100644 (file)
@@ -22,7 +22,6 @@
 #define RESET_VECT             0x00
 #define SW_RESET_ADDR          0x94
 
-extern void berlin_secondary_startup(void);
 extern u32 boot_inst;
 
 static void __iomem *cpu_ctrl;
@@ -85,7 +84,7 @@ static void __init berlin_smp_prepare_cpus(unsigned int max_cpus)
         * Write the secondary startup address into the SW reset address
         * vector. This is used by boot_inst.
         */
-       writel(virt_to_phys(berlin_secondary_startup), vectors_base + SW_RESET_ADDR);
+       writel(virt_to_phys(secondary_startup), vectors_base + SW_RESET_ADDR);
 
        iounmap(vectors_base);
 unmap_scu:
index 6b7b303..659db19 100644 (file)
@@ -6,4 +6,4 @@ CFLAGS_platmcpm.o       := -march=armv7-a
 
 obj-y  += hisilicon.o
 obj-$(CONFIG_MCPM)             += platmcpm.o
-obj-$(CONFIG_SMP)              += platsmp.o hotplug.o headsmp.o
+obj-$(CONFIG_SMP)              += platsmp.o hotplug.o
index 92a682d..c7648ef 100644 (file)
@@ -12,7 +12,6 @@ extern void hi3xxx_cpu_die(unsigned int cpu);
 extern int hi3xxx_cpu_kill(unsigned int cpu);
 extern void hi3xxx_set_cpu(int cpu, bool enable);
 
-extern void hisi_secondary_startup(void);
 extern struct smp_operations hix5hd2_smp_ops;
 extern void hix5hd2_set_cpu(int cpu, bool enable);
 extern void hix5hd2_cpu_die(unsigned int cpu);
diff --git a/arch/arm/mach-hisi/headsmp.S b/arch/arm/mach-hisi/headsmp.S
deleted file mode 100644 (file)
index 81e35b1..0000000
+++ /dev/null
@@ -1,16 +0,0 @@
-/*
- *  Copyright (c) 2014 Hisilicon Limited.
- *  Copyright (c) 2014 Linaro Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-#include <linux/linkage.h>
-#include <linux/init.h>
-
-       __CPUINIT
-
-ENTRY(hisi_secondary_startup)
-       bl      v7_invalidate_l1
-       b       secondary_startup
index 8880c8e..5174412 100644 (file)
@@ -118,7 +118,7 @@ static int hix5hd2_boot_secondary(unsigned int cpu, struct task_struct *idle)
 {
        phys_addr_t jumpaddr;
 
-       jumpaddr = virt_to_phys(hisi_secondary_startup);
+       jumpaddr = virt_to_phys(secondary_startup);
        hix5hd2_set_scu_boot_addr(HIX5HD2_BOOT_ADDRESS, jumpaddr);
        hix5hd2_set_cpu(cpu, true);
        arch_send_wakeup_ipi_mask(cpumask_of(cpu));
@@ -156,7 +156,7 @@ static int hip01_boot_secondary(unsigned int cpu, struct task_struct *idle)
        struct device_node *node;
 
 
-       jumpaddr = virt_to_phys(hisi_secondary_startup);
+       jumpaddr = virt_to_phys(secondary_startup);
        hip01_set_boot_addr(HIP01_BOOT_ADDRESS, jumpaddr);
 
        node = of_find_compatible_node(NULL, NULL, "hisilicon,hip01-sysctrl");
index de5047c..b5e9768 100644 (file)
@@ -25,7 +25,6 @@ diag_reg_offset:
        .endm
 
 ENTRY(v7_secondary_startup)
-       bl      v7_invalidate_l1
        set_diag_reg
        b       secondary_startup
 ENDPROC(v7_secondary_startup)
index 08d5ed4..48e4c4b 100644 (file)
@@ -21,7 +21,6 @@
 
 ENTRY(mvebu_cortex_a9_secondary_startup)
 ARM_BE8(setend be)
-       bl      v7_invalidate_l1
        bl      armada_38x_scu_power_up
        b       secondary_startup
 ENDPROC(mvebu_cortex_a9_secondary_startup)
index d86fe33..209d9fc 100644 (file)
@@ -15,7 +15,6 @@
  * ready for them to initialise.
  */
 ENTRY(sirfsoc_secondary_startup)
-       bl v7_invalidate_l1
         mrc     p15, 0, r0, c0, c0, 5
         and     r0, r0, #15
         adr     r4, 1f
index 39bca96..492c048 100644 (file)
@@ -17,4 +17,3 @@ extern char rockchip_secondary_trampoline;
 extern char rockchip_secondary_trampoline_end;
 
 extern unsigned long rockchip_boot_fn;
-extern void rockchip_secondary_startup(void);
index 46c22de..d69708b 100644 (file)
 #include <linux/linkage.h>
 #include <linux/init.h>
 
-ENTRY(rockchip_secondary_startup)
-       mrc     p15, 0, r0, c0, c0, 0   @ read main ID register
-       ldr     r1, =0x00000c09         @ Cortex-A9 primary part number
-       teq     r0, r1
-       beq     v7_invalidate_l1
-       b       secondary_startup
-ENDPROC(rockchip_secondary_startup)
-
 ENTRY(rockchip_secondary_trampoline)
        ldr     pc, 1f
 ENDPROC(rockchip_secondary_trampoline)
index 5b4ca3c..2e6ab67 100644 (file)
@@ -149,8 +149,7 @@ static int __cpuinit rockchip_boot_secondary(unsigned int cpu,
                 * sram_base_addr + 8: start address for pc
                 * */
                udelay(10);
-               writel(virt_to_phys(rockchip_secondary_startup),
-                       sram_base_addr + 8);
+               writel(virt_to_phys(secondary_startup), sram_base_addr + 8);
                writel(0xDEADBEAF, sram_base_addr + 4);
                dsb_sev();
        }
@@ -189,7 +188,7 @@ static int __init rockchip_smp_prepare_sram(struct device_node *node)
        }
 
        /* set the boot function for the sram code */
-       rockchip_boot_fn = virt_to_phys(rockchip_secondary_startup);
+       rockchip_boot_fn = virt_to_phys(secondary_startup);
 
        /* copy the trampoline to sram, that runs during startup of the core */
        memcpy(sram_base_addr, &rockchip_secondary_trampoline, trampoline_sz);
index afc60ba..476092b 100644 (file)
@@ -14,7 +14,6 @@ extern void shmobile_smp_sleep(void);
 extern void shmobile_smp_hook(unsigned int cpu, unsigned long fn,
                              unsigned long arg);
 extern int shmobile_smp_cpu_disable(unsigned int cpu);
-extern void shmobile_invalidate_start(void);
 extern void shmobile_boot_scu(void);
 extern void shmobile_smp_scu_prepare_cpus(unsigned int max_cpus);
 extern void shmobile_smp_scu_cpu_die(unsigned int cpu);
index 69df8bf..fa5248c 100644 (file)
@@ -22,7 +22,7 @@
  * Boot code for secondary CPUs.
  *
  * First we turn on L1 cache coherency for our CPU. Then we jump to
- * shmobile_invalidate_start that invalidates the cache and hands over control
+ * secondary_startup that invalidates the cache and hands over control
  * to the common ARM startup code.
  */
 ENTRY(shmobile_boot_scu)
@@ -36,7 +36,7 @@ ENTRY(shmobile_boot_scu)
        bic     r2, r2, r3              @ Clear bits of our CPU (Run Mode)
        str     r2, [r0, #8]            @ write back
 
-       b       shmobile_invalidate_start
+       b       secondary_startup
 ENDPROC(shmobile_boot_scu)
 
        .text
index 50c4915..330c1fc 100644 (file)
 #include <asm/assembler.h>
 #include <asm/memory.h>
 
-#ifdef CONFIG_SMP
-ENTRY(shmobile_invalidate_start)
-       bl      v7_invalidate_l1
-       b       secondary_startup
-ENDPROC(shmobile_invalidate_start)
-#endif
-
 /*
  * Reset vector for secondary CPUs.
  * This will be mapped at address 0 by SBAR register.
index f483b56..b0790fc 100644 (file)
@@ -133,7 +133,7 @@ void __init shmobile_smp_apmu_prepare_cpus(unsigned int max_cpus,
 int shmobile_smp_apmu_boot_secondary(unsigned int cpu, struct task_struct *idle)
 {
        /* For this particular CPU register boot vector */
-       shmobile_smp_hook(cpu, virt_to_phys(shmobile_invalidate_start), 0);
+       shmobile_smp_hook(cpu, virt_to_phys(secondary_startup), 0);
 
        return apmu_wrap(cpu, apmu_power_on);
 }
index a0f3b1c..767c09e 100644 (file)
@@ -31,7 +31,6 @@
 
 #define RSTMGR_MPUMODRST_CPU1          0x2     /* CPU1 Reset */
 
-extern void socfpga_secondary_startup(void);
 extern void __iomem *socfpga_scu_base_addr;
 
 extern void socfpga_init_clocks(void);
index f65ea0a..5bb0164 100644 (file)
@@ -30,8 +30,3 @@ ENTRY(secondary_trampoline)
 1:     .long   .
        .long   socfpga_cpu1start_addr
 ENTRY(secondary_trampoline_end)
-
-ENTRY(socfpga_secondary_startup)
-       bl      v7_invalidate_l1
-       b       secondary_startup
-ENDPROC(socfpga_secondary_startup)
index c64d89b..79c5336 100644 (file)
@@ -40,7 +40,7 @@ static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
 
                memcpy(phys_to_virt(0), &secondary_trampoline, trampoline_size);
 
-               writel(virt_to_phys(socfpga_secondary_startup),
+               writel(virt_to_phys(secondary_startup),
                       sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff));
 
                flush_cache_all();
index e48a744..fffad24 100644 (file)
@@ -19,7 +19,7 @@ obj-$(CONFIG_ARCH_TEGRA_3x_SOC)               += pm-tegra30.o
 ifeq ($(CONFIG_CPU_IDLE),y)
 obj-$(CONFIG_ARCH_TEGRA_3x_SOC)                += cpuidle-tegra30.o
 endif
-obj-$(CONFIG_SMP)                      += platsmp.o headsmp.o
+obj-$(CONFIG_SMP)                      += platsmp.o
 obj-$(CONFIG_HOTPLUG_CPU)               += hotplug.o
 
 obj-$(CONFIG_ARCH_TEGRA_114_SOC)       += sleep-tegra30.o
diff --git a/arch/arm/mach-tegra/headsmp.S b/arch/arm/mach-tegra/headsmp.S
deleted file mode 100644 (file)
index 2072e73..0000000
+++ /dev/null
@@ -1,12 +0,0 @@
-#include <linux/linkage.h>
-#include <linux/init.h>
-
-#include "sleep.h"
-
-        .section ".text.head", "ax"
-
-ENTRY(tegra_secondary_startup)
-        check_cpu_part_num 0xc09, r8, r9
-        bleq    v7_invalidate_l1
-        b       secondary_startup
-ENDPROC(tegra_secondary_startup)
index 894c5c4..6fd9db5 100644 (file)
@@ -94,7 +94,7 @@ void __init tegra_cpu_reset_handler_init(void)
        __tegra_cpu_reset_handler_data[TEGRA_RESET_MASK_PRESENT] =
                *((u32 *)cpu_possible_mask);
        __tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_SECONDARY] =
-               virt_to_phys((void *)tegra_secondary_startup);
+               virt_to_phys((void *)secondary_startup);
 #endif
 
 #ifdef CONFIG_PM_SLEEP
index 76a9343..0aee012 100644 (file)
@@ -36,7 +36,6 @@ extern unsigned long __tegra_cpu_reset_handler_data[TEGRA_RESET_DATA_SIZE];
 void __tegra_cpu_reset_handler_start(void);
 void __tegra_cpu_reset_handler(void);
 void __tegra_cpu_reset_handler_end(void);
-void tegra_secondary_startup(void);
 
 #ifdef CONFIG_PM_SLEEP
 #define tegra_cpu_lp1_mask \
index 382c60e..7038cae 100644 (file)
@@ -17,8 +17,6 @@
 #ifndef __MACH_ZYNQ_COMMON_H__
 #define __MACH_ZYNQ_COMMON_H__
 
-void zynq_secondary_startup(void);
-
 extern int zynq_slcr_init(void);
 extern int zynq_early_slcr_init(void);
 extern void zynq_slcr_system_reset(void);
index dd8c071..045c727 100644 (file)
@@ -22,8 +22,3 @@ zynq_secondary_trampoline_jump:
 .globl zynq_secondary_trampoline_end
 zynq_secondary_trampoline_end:
 ENDPROC(zynq_secondary_trampoline)
-
-ENTRY(zynq_secondary_startup)
-       bl      v7_invalidate_l1
-       b       secondary_startup
-ENDPROC(zynq_secondary_startup)
index 52d768f..f66816c 100644 (file)
@@ -87,10 +87,9 @@ int zynq_cpun_start(u32 address, int cpu)
 }
 EXPORT_SYMBOL(zynq_cpun_start);
 
-static int zynq_boot_secondary(unsigned int cpu,
-                                               struct task_struct *idle)
+static int zynq_boot_secondary(unsigned int cpu, struct task_struct *idle)
 {
-       return zynq_cpun_start(virt_to_phys(zynq_secondary_startup), cpu);
+       return zynq_cpun_start(virt_to_phys(secondary_startup), cpu);
 }
 
 /*
index 3d1054f..75ae721 100644 (file)
@@ -336,7 +336,7 @@ __v7_pj4b_setup:
 __v7_setup:
        adr     r12, __v7_setup_stack           @ the local stack
        stmia   r12, {r0-r5, r7, r9, r11, lr}
-       bl      v7_flush_dcache_louis
+       bl      v7_invalidate_l1
        ldmia   r12, {r0-r5, r7, r9, r11, lr}
 
        mrc     p15, 0, r0, c0, c0, 0           @ read main ID register