fix(intel): update boot scratch to indicate to Uboot is PSCI ON

There is a use case where kernel requested ATF to power off/on only CPU0.
However, after ATF power off/on CPU0, CPU0 did not back into the state
to wait for ATF. Instead, CPU0 continue to reentry SPL boot sequence
because CPU0 is master/primary core. This causing the system reboot from
SPL again, while the slave core still in kernel.

To resolve this, ATF is set the boot scratch register 8 bit 17 whenever
it is a request from kernel to power off/on only CPU0. So, if this boot
scratch bit is set, CPU 0 will be able to put into a state to wait for
ATF.

Signed-off-by: Jit Loon Lim <jit.loon.lim@intel.com>
Change-Id: Ia0228c5396beaa479858f5bd02fc05139efd2423

diff --git a/plat/intel/soc/common/socfpga_psci.c b/plat/intel/soc/common/socfpga_psci.c
index 5fd6559f2eae1725961186975a97b8a920d11c6f..bdece935c551c0958034990a64c272574b13957a 100644 (file)
--- a/plat/intel/soc/common/socfpga_psci.c
+++ b/plat/intel/soc/common/socfpga_psci.c
@@ -14,6 +14,7 @@
 #include "socfpga_mailbox.h"
 #include "socfpga_plat_def.h"
 #include "socfpga_reset_manager.h"
+#include "socfpga_system_manager.h"
 #include "socfpga_sip_svc.h"
 
 
@@ -38,12 +39,19 @@ void socfpga_cpu_standby(plat_local_state_t cpu_state)
 int socfpga_pwr_domain_on(u_register_t mpidr)
 {
        unsigned int cpu_id = plat_core_pos_by_mpidr(mpidr);
+       uint32_t psci_boot = 0x00;
 
        VERBOSE("%s: mpidr: 0x%lx\n", __func__, mpidr);
 
        if (cpu_id == -1)
                return PSCI_E_INTERN_FAIL;
 
+       if (cpu_id == 0x00) {
+               psci_boot = mmio_read_32(SOCFPGA_SYSMGR(BOOT_SCRATCH_COLD_8));
+               psci_boot |= 0x20000; /* bit 17 */
+               mmio_write_32(SOCFPGA_SYSMGR(BOOT_SCRATCH_COLD_8), psci_boot);
+       }
+
        mmio_write_64(PLAT_CPUID_RELEASE, cpu_id);
 
        /* release core reset */