1 files changed, 92 insertions, 0 deletions

diff --git a/arch/sh/kernel/cpu/shmobile/pm.c b/arch/sh/kernel/cpu/shmobile/pm.c
new file mode 100644
index 00000000000..8c067adf683
--- /dev/null
+++ b/arch/sh/kernel/cpu/shmobile/pm.c
@@ -0,0 +1,92 @@
+/*
+ * arch/sh/kernel/cpu/sh4a/pm-sh_mobile.c
+ *
+ * Power management support code for SuperH Mobile
+ *
+ *  Copyright (C) 2009 Magnus Damm
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/suspend.h>
+#include <asm/suspend.h>
+#include <asm/uaccess.h>
+
+/*
+ * Sleep modes available on SuperH Mobile:
+ *
+ * Sleep mode is just plain "sleep" instruction
+ * Sleep Self-Refresh mode is above plus RAM put in Self-Refresh
+ * Standby Self-Refresh mode is above plus stopped clocks
+ */
+#define SUSP_MODE_SLEEP         (SUSP_SH_SLEEP)
+#define SUSP_MODE_SLEEP_SF      (SUSP_SH_SLEEP | SUSP_SH_SF)
+#define SUSP_MODE_STANDBY_SF    (SUSP_SH_STANDBY | SUSP_SH_SF)
+
+/*
+ * The following modes are not there yet:
+ *
+ * R-standby mode is unsupported, but will be added in the future
+ * U-standby mode is low priority since it needs bootloader hacks
+ *
+ * All modes should be tied in with cpuidle. But before that can
+ * happen we need to keep track of enabled hardware blocks so we
+ * can avoid entering sleep modes that stop clocks to hardware
+ * blocks that are in use even though the cpu core is idle.
+ */
+
+extern const unsigned char sh_mobile_standby[];
+extern const unsigned int sh_mobile_standby_size;
+
+static void sh_mobile_call_standby(unsigned long mode)
+{
+        extern void *vbr_base;
+        void *onchip_mem = (void *)0xe5200000; /* ILRAM */
+        void (*standby_onchip_mem)(unsigned long) = onchip_mem;
+
+        /* Note: Wake up from sleep may generate exceptions!
+         * Setup VBR to point to on-chip ram if self-refresh is
+         * going to be used.
+         */
+        if (mode & SUSP_SH_SF)
+                asm volatile("ldc %0, vbr" : : "r" (onchip_mem) : "memory");
+
+        /* Copy the assembly snippet to the otherwise ununsed ILRAM */
+        memcpy(onchip_mem, sh_mobile_standby, sh_mobile_standby_size);
+        wmb();
+        ctrl_barrier();
+
+        /* Let assembly snippet in on-chip memory handle the rest */
+        standby_onchip_mem(mode);
+
+        /* Put VBR back in System RAM again */
+        if (mode & SUSP_SH_SF)
+                asm volatile("ldc %0, vbr" : : "r" (&vbr_base) : "memory");
+}
+
+static int sh_pm_enter(suspend_state_t state)
+{
+        local_irq_disable();
+        set_bl_bit();
+        sh_mobile_call_standby(SUSP_MODE_STANDBY_SF);
+        local_irq_disable();
+        clear_bl_bit();
+        return 0;
+}
+
+static struct platform_suspend_ops sh_pm_ops = {
+        .enter          = sh_pm_enter,
+        .valid          = suspend_valid_only_mem,
+};
+
+static int __init sh_pm_init(void)
+{
+        suspend_set_ops(&sh_pm_ops);
+        return 0;
+}
+
+late_initcall(sh_pm_init);