Send power management events to the Trusted OS (TLK)
This patch adds PM handlers to TLKD for the system suspend/resume and
system poweroff/reset cases. TLK expects all SMCs through a single
handler, which then fork out into multiple handlers depending on the
SMC. We tap into the same single entrypoint by restoring the S-EL1
context before passing the PM event via register 'x0'. On completion
of the PM event, TLK sends a completion SMC and TLKD then moves on
with the PM process.
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/services/spd/tlkd/tlkd_pm.c b/services/spd/tlkd/tlkd_pm.c
index 5f2bae3..1eff0aa 100644
--- a/services/spd/tlkd/tlkd_pm.c
+++ b/services/spd/tlkd/tlkd_pm.c
@@ -28,7 +28,17 @@
* POSSIBILITY OF SUCH DAMAGE.
*/
+#include <arch_helpers.h>
+#include <assert.h>
+#include <bl_common.h>
+#include <context_mgmt.h>
+#include <debug.h>
#include <psci.h>
+#include <tlk.h>
+
+#include "tlkd_private.h"
+
+extern tlk_context_t tlk_ctx;
#define MPIDR_CPU0 0x80000000
@@ -46,9 +56,101 @@
}
/*******************************************************************************
+ * This cpu is being suspended. Inform TLK of the SYSTEM_SUSPEND event, so
+ * that it can pass this information to its Trusted Apps.
+ ******************************************************************************/
+static void cpu_suspend_handler(uint64_t suspend_level)
+{
+ gp_regs_t *gp_regs;
+ int cpu = read_mpidr() & MPIDR_CPU_MASK;
+ int32_t rc = 0;
+
+ /*
+ * TLK runs only on CPU0 and suspends its Trusted Apps during
+ * SYSTEM_SUSPEND. It has no role to play during CPU_SUSPEND.
+ */
+ if ((cpu != 0) || (suspend_level != PLAT_MAX_PWR_LVL))
+ return;
+
+ /* pass system suspend event to TLK */
+ gp_regs = get_gpregs_ctx(&tlk_ctx.cpu_ctx);
+ write_ctx_reg(gp_regs, CTX_GPREG_X0, TLK_SYSTEM_SUSPEND);
+
+ /* Program the entry point and enter TLK */
+ rc = tlkd_synchronous_sp_entry(&tlk_ctx);
+
+ /*
+ * Read the response from TLK. A non-zero return means that
+ * something went wrong while communicating with it.
+ */
+ if (rc != 0)
+ panic();
+}
+
+/*******************************************************************************
+ * This cpu is being resumed. Inform TLK of the SYSTEM_SUSPEND exit, so
+ * that it can pass this information to its Trusted Apps.
+ ******************************************************************************/
+static void cpu_resume_handler(uint64_t suspend_level)
+{
+ gp_regs_t *gp_regs;
+ int cpu = read_mpidr() & MPIDR_CPU_MASK;
+ int32_t rc = 0;
+
+ /*
+ * TLK runs only on CPU0 and resumes its Trusted Apps during
+ * SYSTEM_SUSPEND exit. It has no role to play during CPU_SUSPEND
+ * exit.
+ */
+ if ((cpu != 0) || (suspend_level != PLAT_MAX_PWR_LVL))
+ return;
+
+ /* pass system resume event to TLK */
+ gp_regs = get_gpregs_ctx(&tlk_ctx.cpu_ctx);
+ write_ctx_reg(gp_regs, CTX_GPREG_X0, TLK_SYSTEM_RESUME);
+
+ /* Program the entry point and enter TLK */
+ rc = tlkd_synchronous_sp_entry(&tlk_ctx);
+
+ /*
+ * Read the response from TLK. A non-zero return means that
+ * something went wrong while communicating with it.
+ */
+ if (rc != 0)
+ panic();
+}
+
+/*******************************************************************************
+ * System is about to be reset. Inform the SP to allow any book-keeping
+ ******************************************************************************/
+static void system_off_handler(void)
+{
+ int cpu = read_mpidr() & MPIDR_CPU_MASK;
+ gp_regs_t *gp_regs;
+
+ /* TLK runs only on CPU0 */
+ if (cpu != 0)
+ return;
+
+ /* pass system off/reset events to TLK */
+ gp_regs = get_gpregs_ctx(&tlk_ctx.cpu_ctx);
+ write_ctx_reg(gp_regs, CTX_GPREG_X0, TLK_SYSTEM_OFF);
+
+ /*
+ * Enter the SP. We do not care about the return value because we
+ * must continue with the shutdown anyway.
+ */
+ (void)tlkd_synchronous_sp_entry(&tlk_ctx);
+}
+
+/*******************************************************************************
* Structure populated by the Dispatcher to be given a chance to perform any
* bookkeeping before PSCI executes a power mgmt. operation.
******************************************************************************/
const spd_pm_ops_t tlkd_pm_ops = {
.svc_migrate_info = cpu_migrate_info,
+ .svc_suspend = cpu_suspend_handler,
+ .svc_suspend_finish = cpu_resume_handler,
+ .svc_system_off = system_off_handler,
+ .svc_system_reset = system_off_handler
};