ARM: imx: replicate the diagnostic register of boot cpu into secondary cores (087bb283) · Commits · 戴 / test

arch/arm/mach-imx/headsmp.S

+12 −0

Original line number	Diff line number	Diff line
		@@ -18,8 +18,20 @@
		.section ".text.head", "ax"

		#ifdef CONFIG_SMP
		diag_reg_offset:
		.word g_diag_reg - .

		.macro set_diag_reg
		adr r0, diag_reg_offset
		ldr r1, [r0]
		add r1, r1, r0 @ r1 = physical &g_diag_reg
		ldr r0, [r1]
		mcr p15, 0, r0, c15, c0, 1 @ write diagnostic register
		.endm

		ENTRY(v7_secondary_startup)
		bl v7_invalidate_l1
		set_diag_reg
		b secondary_startup
		ENDPROC(v7_secondary_startup)
		#endif

+14 −0

Original line number	Diff line number	Diff line
		@@ -12,6 +12,7 @@

		#include <linux/init.h>
		#include <linux/smp.h>
		#include <asm/cacheflush.h>
		#include <asm/page.h>
		#include <asm/smp_scu.h>
		#include <asm/mach/map.h>
		@@ -21,6 +22,7 @@

		#define SCU_STANDBY_ENABLE (1 << 5)

		u32 g_diag_reg;
		static void __iomem *scu_base;

		static struct map_desc scu_io_desc __initdata = {
		@@ -80,6 +82,18 @@ void imx_smp_prepare(void)
		static void __init imx_smp_prepare_cpus(unsigned int max_cpus)
		{
		imx_smp_prepare();

		/*
		* The diagnostic register holds the errata bits. Mostly bootloader
		* does not bring up secondary cores, so that when errata bits are set
		* in bootloader, they are set only for boot cpu. But on a SMP
		* configuration, it should be equally done on every single core.
		* Read the register from boot cpu here, and will replicate it into
		* secondary cores when booting them.
		*/
		asm("mrc p15, 0, %0, c15, c0, 1" : "=r" (g_diag_reg) : : "cc");
		__cpuc_flush_dcache_area(&g_diag_reg, sizeof(g_diag_reg));
		outer_clean_range(__pa(&g_diag_reg), __pa(&g_diag_reg + 1));
		}

		struct smp_operations imx_smp_ops __initdata = {