diff options
Diffstat (limited to 'arch/arm/cpu/armv8')
| -rw-r--r-- | arch/arm/cpu/armv8/Makefile | 1 | ||||
| -rw-r--r-- | arch/arm/cpu/armv8/cpu.c | 14 | ||||
| -rw-r--r-- | arch/arm/cpu/armv8/lowlevel_init.S | 44 | ||||
| -rw-r--r-- | arch/arm/cpu/armv8/start.S | 5 |
4 files changed, 61 insertions, 3 deletions
diff --git a/arch/arm/cpu/armv8/Makefile b/arch/arm/cpu/armv8/Makefile index 28ba786207..e780afcde2 100644 --- a/arch/arm/cpu/armv8/Makefile +++ b/arch/arm/cpu/armv8/Makefile @@ -26,3 +26,4 @@ obj-$(CONFIG_S32V234) += s32v234/ obj-$(CONFIG_ARCH_ZYNQMP) += zynqmp/ obj-$(CONFIG_TARGET_HIKEY) += hisilicon/ obj-$(CONFIG_ARMV8_PSCI) += psci.o +obj-$(CONFIG_ARCH_SUNXI) += lowlevel_init.o diff --git a/arch/arm/cpu/armv8/cpu.c b/arch/arm/cpu/armv8/cpu.c index 5dcb5e290b..28a27f724e 100644 --- a/arch/arm/cpu/armv8/cpu.c +++ b/arch/arm/cpu/armv8/cpu.c @@ -17,6 +17,20 @@ #include <asm/secure.h> #include <linux/compiler.h> +/* + * sdelay() - simple spin loop. + * + * Will delay execution by roughly (@loops * 2) cycles. + * This is necessary to be used before timers are accessible. + * + * A value of "0" will results in 2^64 loops. + */ +void sdelay(unsigned long loops) +{ + __asm__ volatile ("1:\n" "subs %0, %0, #1\n" + "b.ne 1b" : "=r" (loops) : "0"(loops) : "cc"); +} + int cleanup_before_linux(void) { /* diff --git a/arch/arm/cpu/armv8/lowlevel_init.S b/arch/arm/cpu/armv8/lowlevel_init.S new file mode 100644 index 0000000000..189e35f0ea --- /dev/null +++ b/arch/arm/cpu/armv8/lowlevel_init.S @@ -0,0 +1,44 @@ +/* + * A lowlevel_init function that sets up the stack to call a C function to + * perform further init. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <asm-offsets.h> +#include <config.h> +#include <linux/linkage.h> + +ENTRY(lowlevel_init) + /* + * Setup a temporary stack. Global data is not available yet. + */ +#if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_STACK) + ldr w0, =CONFIG_SPL_STACK +#else + ldr w0, =CONFIG_SYS_INIT_SP_ADDR +#endif + bic sp, x0, #0xf /* 16-byte alignment for ABI compliance */ + + /* + * Save the old LR(passed in x29) and the current LR to stack + */ + stp x29, x30, [sp, #-16]! + + /* + * Call the very early init function. This should do only the + * absolute bare minimum to get started. It should not: + * + * - set up DRAM + * - use global_data + * - clear BSS + * - try to start a console + * + * For boards with SPL this should be empty since SPL can do all of + * this init in the SPL board_init_f() function which is called + * immediately after this. + */ + bl s_init + ldp x29, x30, [sp] + ret +ENDPROC(lowlevel_init) diff --git a/arch/arm/cpu/armv8/start.S b/arch/arm/cpu/armv8/start.S index 4f5f6d8020..140609de08 100644 --- a/arch/arm/cpu/armv8/start.S +++ b/arch/arm/cpu/armv8/start.S @@ -19,8 +19,6 @@ .globl _start _start: - b reset - #ifdef CONFIG_ENABLE_ARM_SOC_BOOT0_HOOK /* * Various SoCs need something special and SoC-specific up front in @@ -28,7 +26,8 @@ _start: * use it here. */ #include <asm/arch/boot0.h> -ARM_SOC_BOOT0_HOOK +#else + b reset #endif .align 3 |