[PATCH 5/6] ARM: highbank: abstract out SCU usage

Rob Herring robherring2 at gmail.com
Fri Oct 26 14:43:07 EDT 2012


From: Rob Herring <rob.herring at calxeda.com>

In preparation for A15 support on ECX-2000, the direct calls to SCU
registers must be conditional. The SCU power mode register is replaced by
a custom register on ECX-2000.

Rather than read the number of cores from the SCU, just hardcode it to 4.
This removes one use of SCU and removes the need for the SCU to be
statically mapped. The cpu initialization will ultimately come from DT.

Signed-off-by: Rob Herring <rob.herring at calxeda.com>
---
 arch/arm/mach-highbank/highbank.c |   21 +++++----------------
 arch/arm/mach-highbank/hotplug.c  |    6 ++----
 arch/arm/mach-highbank/platsmp.c  |    7 +++----
 arch/arm/mach-highbank/pm.c       |    3 ---
 arch/arm/mach-highbank/sysregs.h  |   19 +++++++++++++++++++
 arch/arm/mach-highbank/system.c   |    2 --
 6 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/arch/arm/mach-highbank/highbank.c b/arch/arm/mach-highbank/highbank.c
index 40e36a5..3da921a 100644
--- a/arch/arm/mach-highbank/highbank.c
+++ b/arch/arm/mach-highbank/highbank.c
@@ -28,30 +28,19 @@
 
 #include <asm/cacheflush.h>
 #include <asm/smp_plat.h>
-#include <asm/smp_scu.h>
 #include <asm/smp_twd.h>
 #include <asm/hardware/arm_timer.h>
 #include <asm/hardware/timer-sp.h>
 #include <asm/hardware/gic.h>
 #include <asm/hardware/cache-l2x0.h>
 #include <asm/mach/arch.h>
-#include <asm/mach/map.h>
 #include <asm/mach/time.h>
 
 #include "core.h"
 #include "sysregs.h"
 
 void __iomem *sregs_base;
-
-#define HB_SCU_VIRT_BASE	0xfee00000
-void __iomem *scu_base_addr = ((void __iomem *)(HB_SCU_VIRT_BASE));
-
-static struct map_desc scu_io_desc __initdata = {
-	.virtual	= HB_SCU_VIRT_BASE,
-	.pfn		= 0, /* run-time */
-	.length		= SZ_4K,
-	.type		= MT_DEVICE,
-};
+void __iomem *scu_base_addr;
 
 static void __init highbank_scu_map_io(void)
 {
@@ -60,13 +49,11 @@ static void __init highbank_scu_map_io(void)
 	/* Get SCU base */
 	asm("mrc p15, 4, %0, c15, c0, 0" : "=r" (base));
 
-	scu_io_desc.pfn = __phys_to_pfn(base);
-	iotable_init(&scu_io_desc, 1);
+	scu_base_addr = ioremap(base, SZ_4K);
 }
 
 static void __init highbank_map_io(void)
 {
-	highbank_scu_map_io();
 	highbank_lluart_map_io();
 }
 
@@ -99,6 +86,9 @@ static void __init highbank_init_irq(void)
 {
 	of_irq_init(irq_match);
 
+	if (of_find_compatible_node(NULL, NULL, "arm,cortex-a9"))
+		highbank_scu_map_io();
+
 #ifdef CONFIG_CACHE_L2X0
 	/* Enable PL310 L2 Cache controller */
 	highbank_smc1(0x102, 0x1);
@@ -145,7 +135,6 @@ static struct sys_timer highbank_timer = {
 static void highbank_power_off(void)
 {
 	hignbank_set_pwr_shutdown();
-	scu_power_mode(scu_base_addr, SCU_PM_POWEROFF);
 
 	while (1)
 		cpu_do_idle();
diff --git a/arch/arm/mach-highbank/hotplug.c b/arch/arm/mach-highbank/hotplug.c
index 2c1b8c3..7b60fac 100644
--- a/arch/arm/mach-highbank/hotplug.c
+++ b/arch/arm/mach-highbank/hotplug.c
@@ -14,13 +14,11 @@
  * this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/smp.h>
 
-#include <asm/smp_scu.h>
 #include <asm/cacheflush.h>
 
 #include "core.h"
+#include "sysregs.h"
 
 extern void secondary_startup(void);
 
@@ -33,7 +31,7 @@ void __ref highbank_cpu_die(unsigned int cpu)
 	flush_cache_all();
 
 	highbank_set_cpu_jump(cpu, secondary_startup);
-	scu_power_mode(scu_base_addr, SCU_PM_POWEROFF);
+	highbank_set_core_pwr();
 
 	cpu_do_idle();
 
diff --git a/arch/arm/mach-highbank/platsmp.c b/arch/arm/mach-highbank/platsmp.c
index fa9560e..1129957 100644
--- a/arch/arm/mach-highbank/platsmp.c
+++ b/arch/arm/mach-highbank/platsmp.c
@@ -42,9 +42,7 @@ static int __cpuinit highbank_boot_secondary(unsigned int cpu, struct task_struc
  */
 static void __init highbank_smp_init_cpus(void)
 {
-	unsigned int i, ncores;
-
-	ncores = scu_get_core_count(scu_base_addr);
+	unsigned int i, ncores = 4;
 
 	/* sanity check */
 	if (ncores > NR_CPUS) {
@@ -65,7 +63,8 @@ static void __init highbank_smp_prepare_cpus(unsigned int max_cpus)
 {
 	int i;
 
-	scu_enable(scu_base_addr);
+	if (scu_base_addr)
+		scu_enable(scu_base_addr);
 
 	/*
 	 * Write the address of secondary startup into the jump table
diff --git a/arch/arm/mach-highbank/pm.c b/arch/arm/mach-highbank/pm.c
index de866f2..74aa135 100644
--- a/arch/arm/mach-highbank/pm.c
+++ b/arch/arm/mach-highbank/pm.c
@@ -19,7 +19,6 @@
 #include <linux/suspend.h>
 
 #include <asm/proc-fns.h>
-#include <asm/smp_scu.h>
 #include <asm/suspend.h>
 
 #include "core.h"
@@ -35,8 +34,6 @@ static int highbank_pm_enter(suspend_state_t state)
 {
 	hignbank_set_pwr_suspend();
 	highbank_set_cpu_jump(0, cpu_resume);
-
-	scu_power_mode(scu_base_addr, SCU_PM_POWEROFF);
 	cpu_suspend(0, highbank_suspend_finish);
 
 	return 0;
diff --git a/arch/arm/mach-highbank/sysregs.h b/arch/arm/mach-highbank/sysregs.h
index 0e91338..e13e8ea 100644
--- a/arch/arm/mach-highbank/sysregs.h
+++ b/arch/arm/mach-highbank/sysregs.h
@@ -17,6 +17,10 @@
 #define _MACH_HIGHBANK__SYSREGS_H_
 
 #include <linux/io.h>
+#include <linux/smp.h>
+#include <asm/smp_plat.h>
+#include <asm/smp_scu.h>
+#include "core.h"
 
 extern void __iomem *sregs_base;
 
@@ -29,24 +33,39 @@ extern void __iomem *sregs_base;
 #define HB_PWR_HARD_RESET		2
 #define HB_PWR_SHUTDOWN			3
 
+#define SREG_CPU_PWR_CTRL(c)		(0x200 + ((c) * 4))
+
+static inline void highbank_set_core_pwr(void)
+{
+	int cpu = cpu_logical_map(smp_processor_id());
+	if (scu_base_addr)
+		scu_power_mode(scu_base_addr, SCU_PM_POWEROFF);
+	else
+		writel_relaxed(1, sregs_base + SREG_CPU_PWR_CTRL(cpu));
+}
+
 static inline void hignbank_set_pwr_suspend(void)
 {
 	writel(HB_PWR_SUSPEND, sregs_base + HB_SREG_A9_PWR_REQ);
+	highbank_set_core_pwr();
 }
 
 static inline void hignbank_set_pwr_shutdown(void)
 {
 	writel(HB_PWR_SHUTDOWN, sregs_base + HB_SREG_A9_PWR_REQ);
+	highbank_set_core_pwr();
 }
 
 static inline void hignbank_set_pwr_soft_reset(void)
 {
 	writel(HB_PWR_SOFT_RESET, sregs_base + HB_SREG_A9_PWR_REQ);
+	highbank_set_core_pwr();
 }
 
 static inline void hignbank_set_pwr_hard_reset(void)
 {
 	writel(HB_PWR_HARD_RESET, sregs_base + HB_SREG_A9_PWR_REQ);
+	highbank_set_core_pwr();
 }
 
 #endif
diff --git a/arch/arm/mach-highbank/system.c b/arch/arm/mach-highbank/system.c
index 82c2723..194a5bb 100644
--- a/arch/arm/mach-highbank/system.c
+++ b/arch/arm/mach-highbank/system.c
@@ -14,7 +14,6 @@
  * this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 #include <linux/io.h>
-#include <asm/smp_scu.h>
 #include <asm/proc-fns.h>
 
 #include "core.h"
@@ -27,7 +26,6 @@ void highbank_restart(char mode, const char *cmd)
 	else
 		hignbank_set_pwr_soft_reset();
 
-	scu_power_mode(scu_base_addr, SCU_PM_POWEROFF);
 	cpu_do_idle();
 }
 
-- 
1.7.10.4




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