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 <andy.gross@linaro.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
This commit is contained in:
Andy Gross 2016-06-03 18:25:23 -05:00
parent d0f6fa7ba2
commit 13e7774780
1 changed files with 45 additions and 18 deletions

View File

@ -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;