[U-Boot] [PATCH v2 03/12] ARM: Factor out reusable psci_get_cpu_stack_top

Jan Kiszka
2015-02-16T12:54:40Z

This algorithm will be useful on Tegra as well, plus we will need it for
making _psci_target_pc per-CPU.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
arch/arm/cpu/armv7/psci.S | 14 ++++++++++++++
arch/arm/cpu/armv7/sunxi/psci.S | 17 +++++++----------
2 files changed, 21 insertions(+), 10 deletions(-)

diff --git a/arch/arm/cpu/armv7/psci.S b/arch/arm/cpu/armv7/psci.S
index e916d71..da47934 100644
--- a/arch/arm/cpu/armv7/psci.S
+++ b/arch/arm/cpu/armv7/psci.S
@@ -170,6 +170,20 @@ ENTRY(psci_cpu_off_common)
bx lr
ENDPROC(psci_cpu_off_common)

+@ expects CPU ID in r4 (will be overwritten) and returns stack top in r5
+ENTRY(psci_get_cpu_stack_top)
+ mov r5, #0x400 @ 1kB of stack per CPU
+ mul r4, r4, r5
+
+ ldr r5, =psci_text_end @ end of monitor text
+ add r5, r5, #0x2000 @ Skip two pages
+ lsr r5, r5, #12 @ Align to start of page
+ lsl r5, r5, #12
+ sub r5, r5, r4 @ here's our stack!
+
+ bx lr
+ENDPROC(psci_get_cpu_stack_top)
+
ENTRY(psci_cpu_entry)
@ Set SMP bit
mrc p15, 0, r0, c1, c0, 1 @ ACTLR
diff --git a/arch/arm/cpu/armv7/sunxi/psci.S b/arch/arm/cpu/armv7/sunxi/psci.S
index c3a8dc1..4372022 100644
--- a/arch/arm/cpu/armv7/sunxi/psci.S
+++ b/arch/arm/cpu/armv7/sunxi/psci.S
@@ -213,6 +213,8 @@ psci_cpu_off:

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

@@ -240,16 +242,11 @@ psci_arch_init:

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

- bx lr
+ bx r6

-text_end:
+ .globl psci_text_end
+psci_text_end:
.popsection
--
2.1.4