diff options
Diffstat (limited to 'arch/arm64/kernel/head.S')
-rw-r--r-- | arch/arm64/kernel/head.S | 61 |
1 files changed, 48 insertions, 13 deletions
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 7090c126797..7009387348b 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -123,8 +123,9 @@ ENTRY(stext) mov x21, x0 // x21=FDT + bl el2_setup // Drop to EL1, w20=cpu_boot_mode bl __calc_phys_offset // x24=PHYS_OFFSET, x28=PHYS_OFFSET-PAGE_OFFSET - bl el2_setup // Drop to EL1 + bl set_cpu_boot_mode_flag mrs x22, midr_el1 // x22=cpuid mov x0, x22 bl lookup_processor_type @@ -150,21 +151,30 @@ ENDPROC(stext) /* * If we're fortunate enough to boot at EL2, ensure that the world is * sane before dropping to EL1. + * + * Returns either BOOT_CPU_MODE_EL1 or BOOT_CPU_MODE_EL2 in x20 if + * booted in EL1 or EL2 respectively. */ ENTRY(el2_setup) mrs x0, CurrentEL cmp x0, #PSR_MODE_EL2t ccmp x0, #PSR_MODE_EL2h, #0x4, ne - ldr x0, =__boot_cpu_mode // Compute __boot_cpu_mode - add x0, x0, x28 - b.eq 1f - str wzr, [x0] // Remember we don't have EL2... + b.ne 1f + mrs x0, sctlr_el2 +CPU_BE( orr x0, x0, #(1 << 25) ) // Set the EE bit for EL2 +CPU_LE( bic x0, x0, #(1 << 25) ) // Clear the EE bit for EL2 + msr sctlr_el2, x0 + b 2f +1: mrs x0, sctlr_el1 +CPU_BE( orr x0, x0, #(3 << 24) ) // Set the EE and E0E bits for EL1 +CPU_LE( bic x0, x0, #(3 << 24) ) // Clear the EE and E0E bits for EL1 + msr sctlr_el1, x0 + mov w20, #BOOT_CPU_MODE_EL1 // This cpu booted in EL1 + isb ret /* Hyp configuration. */ -1: ldr w1, =BOOT_CPU_MODE_EL2 - str w1, [x0, #4] // This CPU has EL2 - mov x0, #(1 << 31) // 64-bit EL1 +2: mov x0, #(1 << 31) // 64-bit EL1 msr hcr_el2, x0 /* Generic timers. */ @@ -181,7 +191,8 @@ ENTRY(el2_setup) /* sctlr_el1 */ mov x0, #0x0800 // Set/clear RES{1,0} bits - movk x0, #0x30d0, lsl #16 +CPU_BE( movk x0, #0x33d0, lsl #16 ) // Set EE and E0E on BE systems +CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems msr sctlr_el1, x0 /* Coprocessor traps. */ @@ -204,10 +215,25 @@ ENTRY(el2_setup) PSR_MODE_EL1h) msr spsr_el2, x0 msr elr_el2, lr + mov w20, #BOOT_CPU_MODE_EL2 // This CPU booted in EL2 eret ENDPROC(el2_setup) /* + * Sets the __boot_cpu_mode flag depending on the CPU boot mode passed + * in x20. See arch/arm64/include/asm/virt.h for more info. + */ +ENTRY(set_cpu_boot_mode_flag) + ldr x1, =__boot_cpu_mode // Compute __boot_cpu_mode + add x1, x1, x28 + cmp w20, #BOOT_CPU_MODE_EL2 + b.ne 1f + add x1, x1, #4 +1: str w20, [x1] // This CPU has booted in EL1 + ret +ENDPROC(set_cpu_boot_mode_flag) + +/* * We need to find out the CPU boot mode long after boot, so we need to * store it in a writable variable. * @@ -225,7 +251,6 @@ ENTRY(__boot_cpu_mode) .quad PAGE_OFFSET #ifdef CONFIG_SMP - .pushsection .smp.pen.text, "ax" .align 3 1: .quad . .quad secondary_holding_pen_release @@ -235,8 +260,9 @@ ENTRY(__boot_cpu_mode) * cores are held until we're ready for them to initialise. */ ENTRY(secondary_holding_pen) - bl __calc_phys_offset // x24=phys offset - bl el2_setup // Drop to EL1 + bl el2_setup // Drop to EL1, w20=cpu_boot_mode + bl __calc_phys_offset // x24=PHYS_OFFSET, x28=PHYS_OFFSET-PAGE_OFFSET + bl set_cpu_boot_mode_flag mrs x0, mpidr_el1 ldr x1, =MPIDR_HWID_BITMASK and x0, x0, x1 @@ -250,7 +276,16 @@ pen: ldr x4, [x3] wfe b pen ENDPROC(secondary_holding_pen) - .popsection + + /* + * Secondary entry point that jumps straight into the kernel. Only to + * be used where CPUs are brought online dynamically by the kernel. + */ +ENTRY(secondary_entry) + bl __calc_phys_offset // x2=phys offset + bl el2_setup // Drop to EL1 + b secondary_startup +ENDPROC(secondary_entry) ENTRY(secondary_startup) /* |