sh: APM/PM support.

This adds some simple PM stubs and the basic APM interfaces,
primarily for use by hp6xx, where the existing userland
expects it.

Signed-off-by: Andriy Skulysh <askulysh@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 88 insertions, 0 deletions

diff --git a/arch/sh/kernel/pm.c b/arch/sh/kernel/pm.c
new file mode 100644
index 00000000000..10ab62c9aed
--- /dev/null
+++ b/arch/sh/kernel/pm.c
@@ -0,0 +1,88 @@
+/*
+ * Generic Power Management Routine
+ *
+ * Copyright (c) 2006 Andriy Skulysh <askulsyh@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License.
+ */
+#include <linux/suspend.h>
+#include <linux/delay.h>
+#include <linux/gfp.h>
+#include <asm/freq.h>
+#include <asm/io.h>
+#include <asm/watchdog.h>
+#include <asm/pm.h>
+
+#define INTR_OFFSET     0x600
+
+#define STBCR           0xffffff82
+#define STBCR2          0xffffff88
+
+#define STBCR_STBY      0x80
+#define STBCR_MSTP2     0x04
+
+#define MCR             0xffffff68
+#define RTCNT           0xffffff70
+
+#define MCR_RMODE       2
+#define MCR_RFSH        4
+
+void pm_enter(void)
+{
+        u8 stbcr, csr;
+        u16 frqcr, mcr;
+        u32 vbr_new, vbr_old;
+
+        set_bl_bit();
+
+        /* set wdt */
+        csr = sh_wdt_read_csr();
+        csr &= ~WTCSR_TME;
+        csr |= WTCSR_CKS_4096;
+        sh_wdt_write_csr(csr);
+        csr = sh_wdt_read_csr();
+        sh_wdt_write_cnt(0);
+
+        /* disable PLL1 */
+        frqcr = ctrl_inw(FRQCR);
+        frqcr &= ~(FRQCR_PLLEN | FRQCR_PSTBY);
+        ctrl_outw(frqcr, FRQCR);
+
+        /* enable standby */
+        stbcr = ctrl_inb(STBCR);
+        ctrl_outb(stbcr | STBCR_STBY | STBCR_MSTP2, STBCR);
+
+        /* set self-refresh */
+        mcr = ctrl_inw(MCR);
+        ctrl_outw(mcr & ~MCR_RFSH, MCR);
+
+        /* set interrupt handler */
+        asm volatile("stc vbr, %0" : "=r" (vbr_old));
+        vbr_new = get_zeroed_page(GFP_ATOMIC);
+        udelay(50);
+        memcpy((void*)(vbr_new + INTR_OFFSET),
+               &wakeup_start, &wakeup_end - &wakeup_start);
+        asm volatile("ldc %0, vbr" : : "r" (vbr_new));
+
+        ctrl_outw(0, RTCNT);
+        ctrl_outw(mcr | MCR_RFSH | MCR_RMODE, MCR);
+
+        cpu_sleep();
+
+        asm volatile("ldc %0, vbr" : : "r" (vbr_old));
+
+        free_page(vbr_new);
+
+        /* enable PLL1 */
+        frqcr = ctrl_inw(FRQCR);
+        frqcr |= FRQCR_PSTBY;
+        ctrl_outw(frqcr, FRQCR);
+        udelay(50);
+        frqcr |= FRQCR_PLLEN;
+        ctrl_outw(frqcr, FRQCR);
+
+        ctrl_outb(stbcr, STBCR);
+
+        clear_bl_bit();
+}