[U-Boot] [PATCH v6 02/15] ARM: Factor out common psci_get_cpu_id

Jan Kiszka
2015-04-13T04:48:07Z

Will be required for obtaining the ID of the current CPU in shared PSCI
functions. The default implementation requires a dense ID space and only
supports a single cluster. Therefore, the functions can be overloaded in
cases where these assumptions do not hold.

CC: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Tested-by: Ian Campbell <ijc@hellion.org.uk>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
---
arch/arm/cpu/armv7/psci.S | 8 ++++++++
arch/arm/cpu/armv7/sunxi/psci.S | 12 +++++++-----
2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/arch/arm/cpu/armv7/psci.S b/arch/arm/cpu/armv7/psci.S
index bf11a34..12ad09b 100644
--- a/arch/arm/cpu/armv7/psci.S
+++ b/arch/arm/cpu/armv7/psci.S
@@ -99,4 +99,12 @@ _smc_psci:
pop {r4-r7, lr}
movs pc, lr @ Return to the kernel

+@ Requires dense and single-cluster CPU ID space
+ENTRY(psci_get_cpu_id)
+ mrc p15, 0, r0, c0, c0, 5 /* read MPIDR */
+ and r0, r0, #0xff /* return CPU ID in cluster */
+ bx lr
+ENDPROC(psci_get_cpu_id)
+.weak psci_get_cpu_id
+
.popsection
diff --git a/arch/arm/cpu/armv7/sunxi/psci.S b/arch/arm/cpu/armv7/sunxi/psci.S
index 07b2d76..bcc419d 100644
--- a/arch/arm/cpu/armv7/sunxi/psci.S
+++ b/arch/arm/cpu/armv7/sunxi/psci.S
@@ -19,6 +19,7 @@

#include <config.h>
#include <asm/gic.h>
+#include <asm/macro.h>
#include <asm/psci.h>
#include <asm/arch/cpu.h>

@@ -290,6 +291,8 @@ psci_cpu_off:

.globl psci_arch_init
psci_arch_init:
+ mov r6, lr
+
movw r4, #(GICD_BASE & 0xffff)
movt r4, #(GICD_BASE >> 16)

@@ -315,18 +318,17 @@ psci_arch_init:
mcr p15, 0, r5, c1, c1, 0 @ Write SCR
isb

- mrc p15, 0, r4, c0, c0, 5 @ MPIDR
- and r4, r4, #3 @ cpu number in cluster
+ bl psci_get_cpu_id
mov r5, #0x400 @ 1kB of stack per CPU
- mul r4, r4, r5
+ mul r0, r0, r5

adr r5, text_end @ end of text
add r5, r5, #0x2000 @ Skip two pages
lsr r5, r5, #12 @ Align to start of page
lsl r5, r5, #12
- sub sp, r5, r4 @ here's our stack!
+ sub sp, r5, r0 @ here's our stack!

- bx lr
+ bx r6

text_end:
.popsection
--
2.1.4