PSCI: Add documentation and fix plat_is_my_cpu_primary()
This patch adds the necessary documentation updates to porting_guide.md
for the changes in the platform interface mandated as a result of the new
PSCI Topology and power state management frameworks. It also adds a
new document `platform-migration-guide.md` to aid the migration of existing
platform ports to the new API.
The patch fixes the implementation and callers of
plat_is_my_cpu_primary() to use w0 as the return parameter as implied by
the function signature rather than x0 which was used previously.
Change-Id: Ic11e73019188c8ba2bd64c47e1729ff5acdcdd5b
diff --git a/plat/arm/css/common/aarch64/css_helpers.S b/plat/arm/css/common/aarch64/css_helpers.S
index 5d5bf86..05bd864 100644
--- a/plat/arm/css/common/aarch64/css_helpers.S
+++ b/plat/arm/css/common/aarch64/css_helpers.S
@@ -77,7 +77,7 @@
* Function to calculate the core position by
* swapping the cluster order. This is necessary in order to
* match the format of the boot information passed by the SCP
- * and read in platform_is_primary_cpu below.
+ * and read in plat_is_my_cpu_primary below.
* -----------------------------------------------------------
*/
func plat_arm_calc_core_pos
@@ -102,6 +102,6 @@
ldr x1, [x1]
ubfx x1, x1, #PRIMARY_CPU_SHIFT, #PRIMARY_CPU_BIT_WIDTH
cmp x0, x1
- cset x0, eq
+ cset w0, eq
ret x9
endfunc plat_is_my_cpu_primary