Tegra: allow platforms to override plat_core_pos_by_mpidr()
This patch makes the default implementation of plat_core_pos_by_mpidr()
as weakly linked, so that platforms can override it with their own.
Tegra186, for one, does not have CPU IDs 2 and 3, so it has its own
implementation of plat_core_pos_by_mpidr().
Change-Id: I7a5319869c01ede3775386cb95af1431792f74b3
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/plat/nvidia/tegra/soc/t186/plat_setup.c b/plat/nvidia/tegra/soc/t186/plat_setup.c
index 7108723..13f867e 100644
--- a/plat/nvidia/tegra/soc/t186/plat_setup.c
+++ b/plat/nvidia/tegra/soc/t186/plat_setup.c
@@ -50,6 +50,13 @@
extern uint64_t tegra_enable_l2_ecc_parity_prot;
/*******************************************************************************
+ * Tegra186 CPU numbers in cluster #0
+ *******************************************************************************
+ */
+#define TEGRA186_CLUSTER0_CORE2 2
+#define TEGRA186_CLUSTER0_CORE3 3
+
+/*******************************************************************************
* The Tegra power domain tree has a single system level power domain i.e. a
* single root node. The first entry in the power domain descriptor specifies
* the number of power domains at the highest power level.
@@ -256,3 +263,40 @@
return (plat_params_from_bl2_t *)(uintptr_t)val;
}
+
+/*******************************************************************************
+ * This function implements a part of the critical interface between the psci
+ * generic layer and the platform that allows the former to query the platform
+ * to convert an MPIDR to a unique linear index. An error code (-1) is returned
+ * in case the MPIDR is invalid.
+ ******************************************************************************/
+int plat_core_pos_by_mpidr(u_register_t mpidr)
+{
+ unsigned int cluster_id, cpu_id, pos;
+
+ cluster_id = (mpidr >> MPIDR_AFF1_SHIFT) & MPIDR_AFFLVL_MASK;
+ cpu_id = (mpidr >> MPIDR_AFF0_SHIFT) & MPIDR_AFFLVL_MASK;
+
+ /*
+ * Validate cluster_id by checking whether it represents
+ * one of the two clusters present on the platform.
+ */
+ if (cluster_id >= PLATFORM_CLUSTER_COUNT)
+ return PSCI_E_NOT_PRESENT;
+
+ /*
+ * Validate cpu_id by checking whether it represents a CPU in
+ * one of the two clusters present on the platform.
+ */
+ if (cpu_id >= PLATFORM_MAX_CPUS_PER_CLUSTER)
+ return PSCI_E_NOT_PRESENT;
+
+ /* calculate the core position */
+ pos = cpu_id + (cluster_id << 2);
+
+ /* check for non-existent CPUs */
+ if (pos == TEGRA186_CLUSTER0_CORE2 || pos == TEGRA186_CLUSTER0_CORE3)
+ return PSCI_E_NOT_PRESENT;
+
+ return pos;
+}