From: Giridhar Maruthy <giridhar.m@xxxxxxxxxxx> This patch puts the secondary processors in hypervisor mode. This is required in cpu hotplug scenario where u-boot is not alive to put the secondary processors to hypervisor mode after the kernel has booted. This patch is almost same as the u-boot patch by Christoffer Dall(cdall@xxxxxxxxxxxxxxx> and Jeremy C. Andrus <jeremya@xxxxxxxxxxxxxxx> https://github.com/columbia/u-boot-arndale/commit/beb8a0d559510da7c44e887cbc705e3c51321c98 Signed-off-by: Giridhar Maruthy <giridhar.m@xxxxxxxxxxx> --- arch/arm/mach-exynos/headsmp.S | 102 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) diff --git a/arch/arm/mach-exynos/headsmp.S b/arch/arm/mach-exynos/headsmp.S index 5364d4b..6124121 100644 --- a/arch/arm/mach-exynos/headsmp.S +++ b/arch/arm/mach-exynos/headsmp.S @@ -12,6 +12,7 @@ */ #include <linux/linkage.h> #include <linux/init.h> +#include <asm/assembler.h> __CPUINIT @@ -20,6 +21,86 @@ * a "holding pen" into which all secondary cores are held until we're * ready for them to initialise. */ + +.arch_extension sec +.arch_extension virt +.text + +.align 5 +/* We use the same vector table for Hyp and Monitor mode, since + * we will only use each once and they don't overlap. + */ +mon_vectors: + .word 0 /* reset */ + .word 0 /* undef */ + b 2f /* smc */ + .word 0 /* pabt */ + .word 0 /* dabt */ + b 1f + .word 0 /* irq */ + .word 0 /* fiq */ + +/* Return directly back to the caller without leaving Hyp mode: */ +1: mrs lr, elr_hyp + mov pc, lr + +/* In monitor mode, set up HVBAR and SCR then return to caller in NS-SVC. */ +2: + mrc p15, 0, r1, c1, c1, 0 @ SCR + /* + * Set SCR.NS=1(needed for setting HVBAR and also returning to NS state) + * .IRQ,FIQ,EA=0 (don't take aborts/exceptions to Monitor mode) + * .FW,AW=1 (CPSR.A,F modifiable in NS state) + * .nET=0 (early termination OK) + * .SCD=0 (SMC in NS mode OK, so we can call secure firmware) + * .HCE=1 (HVC does Hyp call) + */ + bic r1, r1, #0x07f + ldr r2, =0x131 + orr r1, r1, r2 + mcr p15, 0, r2, c1, c1, 0 @ SCR + isb + ldr r2, =mon_vectors + + + adr r4, 1f + ldmia r4, {r5} + sub r4, r4, r5 + add r2, r2, r4 + + mcr p15, 4, r2, c12, c0, 0 @ set HVBAR + /* ...and return to calling code in NS state */ + movs pc, lr + + + .globl monitor_init +monitor_init: + ldr ip, =mon_vectors + + adr r4, 1f + ldmia r4, {r5} + sub r4, r4, r5 + add ip, ip, r4 + + mov pc, lr + + /* Try to go into NS-SVC: void enter_ns(void); */ + .globl enter_ns +enter_ns: + smc #0 + mov pc, lr + + /* void enter_hyp(void); */ + .globl enter_hyp +enter_hyp: + /* Now we're in NS-SVC, make a Hyp call to get into Hyp mode */ + mov r0, lr + mov r1, sp + hvc #0 + /* We will end up here in NS-Hyp. */ + mov sp, r1 + mov pc, r0 + ENTRY(exynos4_secondary_startup) mrc p15, 0, r0, c0, c0, 5 and r0, r0, #15 @@ -31,6 +112,27 @@ pen: ldr r7, [r6] cmp r7, r0 bne pen + ldr r1, =__boot_cpu_mode + add r1, r1, r4 + ldr r2, [r1] + mrs r0, cpsr + ands r0, r0, #MODE_MASK + subs r1, r0, r2 + beq 3f + subs r2, r2, #HYP_MODE + bne 3f + + /* Setting NSACR to allow coprocessor access from non-secure mode */ + mrc p15, 0, r0, c1, c1, 2 + movw r1, #0x3fff + orr r0, r0, r1 + mcr p15, 0, r0, c1, c1, 2 +5: + bl monitor_init + bl enter_ns + bl enter_hyp + +3: /* * we've been released from the holding pen: secondary_stack * should now contain the SVC stack for this core -- 1.7.9.5 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
