[PATCH 6/6] ARM: tegra114: add CPU hotplug support
Joseph Lo
josephl at nvidia.com
Wed May 15 06:27:24 EDT 2013
The Tegra114 is a quad cores SoC. Each core can be hotplugged including
CPU0. The hotplug sequence can be controlled by setting event trigger in
flow controller. Then the flow controller will take care all the power
sequence that include CPU up and down.
Signed-off-by: Joseph Lo <josephl at nvidia.com>
---
arch/arm/mach-tegra/Makefile | 1 +
arch/arm/mach-tegra/hotplug.c | 2 ++
arch/arm/mach-tegra/reset-handler.S | 11 ++++++++++-
arch/arm/mach-tegra/sleep-tegra30.S | 27 +++++++++++++++++++++++----
arch/arm/mach-tegra/sleep.h | 2 ++
5 files changed, 38 insertions(+), 5 deletions(-)
diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile
index d011f0a..98b184e 100644
--- a/arch/arm/mach-tegra/Makefile
+++ b/arch/arm/mach-tegra/Makefile
@@ -30,6 +30,7 @@ obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
obj-$(CONFIG_TEGRA_PCI) += pcie.o
obj-$(CONFIG_ARCH_TEGRA_114_SOC) += tegra114_speedo.o
+obj-$(CONFIG_ARCH_TEGRA_114_SOC) += sleep-tegra30.o
ifeq ($(CONFIG_CPU_IDLE),y)
obj-$(CONFIG_ARCH_TEGRA_114_SOC) += cpuidle-tegra114.o
endif
diff --git a/arch/arm/mach-tegra/hotplug.c b/arch/arm/mach-tegra/hotplug.c
index 184914a..d07f152 100644
--- a/arch/arm/mach-tegra/hotplug.c
+++ b/arch/arm/mach-tegra/hotplug.c
@@ -55,4 +55,6 @@ void __init tegra_hotplug_init(void)
tegra_hotplug_shutdown = tegra20_hotplug_shutdown;
if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC) && tegra_chip_id == TEGRA30)
tegra_hotplug_shutdown = tegra30_hotplug_shutdown;
+ if (IS_ENABLED(CONFIG_ARCH_TEGRA_114_SOC) && tegra_chip_id == TEGRA114)
+ tegra_hotplug_shutdown = tegra30_hotplug_shutdown;
}
diff --git a/arch/arm/mach-tegra/reset-handler.S b/arch/arm/mach-tegra/reset-handler.S
index 893f6b7..5af3a7d 100644
--- a/arch/arm/mach-tegra/reset-handler.S
+++ b/arch/arm/mach-tegra/reset-handler.S
@@ -38,18 +38,24 @@
* CPU boot vector when restarting the a CPU following
* an LP2 transition. Also branched to by LP0 and LP1 resume after
* re-enabling sdram.
+ *
+ * r6: SoC ID << 8
*/
ENTRY(tegra_resume)
bl v7_invalidate_l1
cpu_id r0
+ tegra_check_soc_id TEGRA114, TEGRA_APB_MISC_BASE, r6, r7
+ beq no_cpu0_chk
+
cmp r0, #0 @ CPU0?
THUMB( it ne )
bne cpu_resume @ no
+no_cpu0_chk:
#ifndef CONFIG_ARCH_TEGRA_2x_SOC
/* Are we on Tegra20? */
- tegra_check_soc_id TEGRA20, TEGRA_APB_MISC_BASE, r6, r7
+ cmp r6, #(TEGRA20 << 8)
beq 1f @ Yes
/* Clear the flow controller flags for this CPU. */
cpu_to_csr_req r1, r0
@@ -186,8 +192,11 @@ __is_not_lp2:
* Can only be secondary boot (initial or hotplug) but CPU 0
* cannot be here.
*/
+ cmp r6, #(TEGRA114 <<8)
+ beq __no_cpu0_chk
cmp r10, #0
bleq __die @ CPU0 cannot be here
+__no_cpu0_chk:
ldr lr, [r12, #RESET_DATA(STARTUP_SECONDARY)]
cmp lr, #0
bleq __die @ no secondary startup handler
diff --git a/arch/arm/mach-tegra/sleep-tegra30.S b/arch/arm/mach-tegra/sleep-tegra30.S
index d29dfcc..ae36fbb 100644
--- a/arch/arm/mach-tegra/sleep-tegra30.S
+++ b/arch/arm/mach-tegra/sleep-tegra30.S
@@ -19,6 +19,7 @@
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
+#include "fuse.h"
#include "sleep.h"
#include "flowctrl.h"
@@ -45,12 +46,17 @@ ENDPROC(tegra30_hotplug_shutdown)
* and powergates it -- flags (in R0) indicate the request type.
* Must never be called for CPU 0.
*
- * corrupts r0-r4, r12
+ * r10 = SoC ID << 8
+ * corrupts r0-r4, r10-r12
*/
ENTRY(tegra30_cpu_shutdown)
cpu_id r3
+ tegra_check_soc_id TEGRA30, TEGRA_APB_MISC_VIRT, r10, r11
+ bne _no_cpu0_chk @ It's not Tegra30
+
cmp r3, #0
moveq pc, lr @ Must never be called for CPU 0
+_no_cpu0_chk:
ldr r12, =TEGRA_FLOW_CTRL_VIRT
cpu_to_csr_reg r1, r3
@@ -65,7 +71,9 @@ ENTRY(tegra30_cpu_shutdown)
movw r12, \
FLOW_CTRL_CSR_INTR_FLAG | FLOW_CTRL_CSR_EVENT_FLAG | \
FLOW_CTRL_CSR_ENABLE
- mov r4, #(1 << 4)
+ cmp r10, #(TEGRA30 << 8)
+ moveq r4, #(1 << 4) @ wfe bitmap
+ movne r4, #(1 << 8) @ wfi bitmap
ARM( orr r12, r12, r4, lsl r3 )
THUMB( lsl r4, r4, r3 )
THUMB( orr r12, r12, r4 )
@@ -79,9 +87,19 @@ delay_1:
cpsid a @ disable imprecise aborts.
ldr r3, [r1] @ read CSR
str r3, [r1] @ clear CSR
+
tst r0, #TEGRA30_POWER_HOTPLUG_SHUTDOWN
+ beq flow_ctrl_setting_for_lp2
+
+ /* flow controller set up for hotplug */
+ mov r3, #FLOW_CTRL_WAITEVENT @ For hotplug
+ b flow_ctrl_done
+flow_ctrl_setting_for_lp2:
+ /* flow controller set up for LP2 */
+ cmp r10, #(TEGRA30 << 8)
moveq r3, #FLOW_CTRL_WAIT_FOR_INTERRUPT @ For LP2
- movne r3, #FLOW_CTRL_WAITEVENT @ For hotplug
+flow_ctrl_done:
+ cmp r10, #(TEGRA30 << 8)
str r3, [r2]
ldr r0, [r2]
b wfe_war
@@ -89,7 +107,8 @@ delay_1:
__cpu_reset_again:
dsb
.align 5
- wfe @ CPU should be power gated here
+ wfeeq @ CPU should be power gated here
+ wfine
wfe_war:
b __cpu_reset_again
diff --git a/arch/arm/mach-tegra/sleep.h b/arch/arm/mach-tegra/sleep.h
index c2cac9a..92a3f0c 100644
--- a/arch/arm/mach-tegra/sleep.h
+++ b/arch/arm/mach-tegra/sleep.h
@@ -25,6 +25,8 @@
+ IO_PPSB_VIRT)
#define TEGRA_CLK_RESET_VIRT (TEGRA_CLK_RESET_BASE - IO_PPSB_PHYS \
+ IO_PPSB_VIRT)
+#define TEGRA_APB_MISC_VIRT (TEGRA_APB_MISC_BASE - IO_APB_PHYS \
+ + IO_APB_VIRT)
#define TEGRA_PMC_VIRT (TEGRA_PMC_BASE - IO_APB_PHYS + IO_APB_VIRT)
/* PMC_SCRATCH37-39 and 41 are used for tegra_pen_lock and idle */
--
1.8.2.2
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