zynqmp: Add bakery_lock to protect APU_PWRCTRL register access

Access to APU_PWRCTRL register is protected during suspend/wakeup pocedure
in order to save valid state. If more than one CPU is accessing this register
it can be left in corrupted state during read-modify-write process.

Signed-off-by: Stefan Krsmanovic <stefan.krsmanovic@aggios.com>
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>

diff --git a/plat/xilinx/zynqmp/pm_service/pm_client.c b/plat/xilinx/zynqmp/pm_service/pm_client.c
index eb986bca40d9006f66acd0035607612909b718e4..d3396dfa9c79060d9c1393b12b01dad76d38ed73 100644 (file)
--- a/plat/xilinx/zynqmp/pm_service/pm_client.c
+++ b/plat/xilinx/zynqmp/pm_service/pm_client.c
@@ -33,6 +33,7 @@
  * for getting information about and changing state of the APU.
  */
 
+#include <bakery_lock.h>
 #include <gicv2.h>
 #include <bl_common.h>
 #include <mmio.h>
@@ -47,6 +48,7 @@
 #define OCM_BANK_3     (OCM_BANK_2 + 0x10000)
 
 #define UNDEFINED_CPUID                (~0)
+DEFINE_BAKERY_LOCK(pm_client_secure_lock);
 
 /* Declaration of linker defined symbol */
 extern unsigned long __BL31_END__;
@@ -162,8 +164,12 @@ const struct pm_proc *primary_proc = &pm_procs_all[0];
  */
 void pm_client_suspend(const struct pm_proc *proc)
 {
+       bakery_lock_get(&pm_client_secure_lock);
+
        /* Set powerdown request */
        mmio_write_32(APU_PWRCTL, mmio_read_32(APU_PWRCTL) | proc->pwrdn_mask);
+
+       bakery_lock_release(&pm_client_secure_lock);
 }
 
 
@@ -177,9 +183,14 @@ void pm_client_abort_suspend(void)
 {
        /* Enable interrupts at processor level (for current cpu) */
        gicv2_cpuif_enable();
+
+       bakery_lock_get(&pm_client_secure_lock);
+
        /* Clear powerdown request */
        mmio_write_32(APU_PWRCTL,
                 mmio_read_32(APU_PWRCTL) & ~primary_proc->pwrdn_mask);
+
+       bakery_lock_release(&pm_client_secure_lock);
 }
 
 /**
@@ -195,8 +206,12 @@ void pm_client_wakeup(const struct pm_proc *proc)
        if (cpuid == UNDEFINED_CPUID)
                return;
 
+       bakery_lock_get(&pm_client_secure_lock);
+
        /* clear powerdown bit for affected cpu */
        uint32_t val = mmio_read_32(APU_PWRCTL);
        val &= ~(proc->pwrdn_mask);
        mmio_write_32(APU_PWRCTL, val);
+
+       bakery_lock_release(&pm_client_secure_lock);
 }