From 13e77747800ef71224a12f787ebd26b27c16ff12 Mon Sep 17 00:00:00 2001 From: Andy Gross Date: Fri, 3 Jun 2016 18:25:23 -0500 Subject: firmware: qcom: scm: Use atomic SCM for cold boot This patch changes the cold_set_boot_addr function to use atomic SCM calls. cold_set_boot_addr required adding qcom_scm_call_atomic2 to support the two arguments going to the smc call. Using atomic removes the need for memory allocation and instead places all arguments in registers. Signed-off-by: Andy Gross Reviewed-by: Stephen Boyd Acked-by: Bjorn Andersson --- drivers/firmware/qcom_scm-32.c | 63 ++++++++++++++++++++++++++++++------------ 1 file changed, 45 insertions(+), 18 deletions(-) (limited to 'drivers/firmware/qcom_scm-32.c') diff --git a/drivers/firmware/qcom_scm-32.c b/drivers/firmware/qcom_scm-32.c index 0883292f640f..5be6a123ac70 100644 --- a/drivers/firmware/qcom_scm-32.c +++ b/drivers/firmware/qcom_scm-32.c @@ -342,6 +342,41 @@ static s32 qcom_scm_call_atomic1(u32 svc, u32 cmd, u32 arg1) return r0; } +/** + * qcom_scm_call_atomic2() - Send an atomic SCM command with two arguments + * @svc_id: service identifier + * @cmd_id: command identifier + * @arg1: first argument + * @arg2: second argument + * + * This shall only be used with commands that are guaranteed to be + * uninterruptable, atomic and SMP safe. + */ +static s32 qcom_scm_call_atomic2(u32 svc, u32 cmd, u32 arg1, u32 arg2) +{ + int context_id; + + register u32 r0 asm("r0") = SCM_ATOMIC(svc, cmd, 2); + register u32 r1 asm("r1") = (u32)&context_id; + register u32 r2 asm("r2") = arg1; + register u32 r3 asm("r3") = arg2; + + asm volatile( + __asmeq("%0", "r0") + __asmeq("%1", "r0") + __asmeq("%2", "r1") + __asmeq("%3", "r2") + __asmeq("%4", "r3") +#ifdef REQUIRES_SEC + ".arch_extension sec\n" +#endif + "smc #0 @ switch to secure world\n" + : "=r" (r0) + : "r" (r0), "r" (r1), "r" (r2), "r" (r3) + ); + return r0; +} + u32 qcom_scm_get_version(void) { int context_id; @@ -378,22 +413,6 @@ u32 qcom_scm_get_version(void) } EXPORT_SYMBOL(qcom_scm_get_version); -/* - * Set the cold/warm boot address for one of the CPU cores. - */ -static int qcom_scm_set_boot_addr(u32 addr, int flags) -{ - struct { - __le32 flags; - __le32 addr; - } cmd; - - cmd.addr = cpu_to_le32(addr); - cmd.flags = cpu_to_le32(flags); - return qcom_scm_call(QCOM_SCM_SVC_BOOT, QCOM_SCM_BOOT_ADDR, - &cmd, sizeof(cmd), NULL, 0); -} - /** * qcom_scm_set_cold_boot_addr() - Set the cold boot address for cpus * @entry: Entry point function for the cpus @@ -423,7 +442,8 @@ int __qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus) set_cpu_present(cpu, false); } - return qcom_scm_set_boot_addr(virt_to_phys(entry), flags); + return qcom_scm_call_atomic2(QCOM_SCM_SVC_BOOT, QCOM_SCM_BOOT_ADDR, + flags, virt_to_phys(entry)); } /** @@ -439,6 +459,10 @@ int __qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus) int ret; int flags = 0; int cpu; + struct { + __le32 flags; + __le32 addr; + } cmd; /* * Reassign only if we are switching from hotplug entry point @@ -454,7 +478,10 @@ int __qcom_scm_set_warm_boot_addr(void *entry, const cpumask_t *cpus) if (!flags) return 0; - ret = qcom_scm_set_boot_addr(virt_to_phys(entry), flags); + cmd.addr = cpu_to_le32(virt_to_phys(entry)); + cmd.flags = cpu_to_le32(flags); + ret = qcom_scm_call(QCOM_SCM_SVC_BOOT, QCOM_SCM_BOOT_ADDR, + &cmd, sizeof(cmd), NULL, 0); if (!ret) { for_each_cpu(cpu, cpus) qcom_scm_wb[cpu].entry = entry; -- cgit v1.2.3