[ARM] 3466/1: [2/3] Support for Philips PNX4008 platform: chip support

Patch from Vitaly Wool

This patch adds basic chip support for PNX4008 ARM platform.
It's basically the same as the previous one, but with the rmk's
comments taken into account.

Signed-off-by: Vitaly Wool <vwool@ru.mvista.com>
Signed-off-by: Dmitry Pervushin <dpervushin@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 184 insertions, 0 deletions

diff --git a/arch/arm/mach-pnx4008/pm.c b/arch/arm/mach-pnx4008/pm.c
new file mode 100644
index 000000000000..3649cd3dfc9a
--- /dev/null
+++ b/arch/arm/mach-pnx4008/pm.c
@@ -0,0 +1,184 @@
+/*
+ * arch/arm/mach-pnx4008/pm.c
+ *
+ * Power Management driver for PNX4008
+ *
+ * Authors: Vitaly Wool, Dmitry Chigirev <source@mvista.com>
+ *
+ * 2005 (c) MontaVista Software, Inc. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ */
+
+#include <linux/pm.h>
+#include <linux/rtc.h>
+#include <linux/sched.h>
+#include <linux/proc_fs.h>
+#include <linux/pm.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+
+#include <asm/io.h>
+#include <asm/mach-types.h>
+#include <asm/cacheflush.h>
+#include <asm/arch/pm.h>
+#include <asm/arch/clock.h>
+
+#define SRAM_VA IO_ADDRESS(PNX4008_IRAM_BASE)
+
+static void *saved_sram;
+
+static struct clk *pll4_clk;
+
+static inline void pnx4008_standby(void)
+{
+        void (*pnx4008_cpu_standby_ptr) (void);
+
+        local_irq_disable();
+        local_fiq_disable();
+
+        clk_disable(pll4_clk);
+
+        /*saving portion of SRAM to be used by suspend function. */
+        memcpy(saved_sram, (void *)SRAM_VA, pnx4008_cpu_standby_sz);
+
+        /*make sure SRAM copy gets physically written into SDRAM.
+           SDRAM will be placed into self-refresh during power down */
+        flush_cache_all();
+
+        /*copy suspend function into SRAM */
+        memcpy((void *)SRAM_VA, pnx4008_cpu_standby, pnx4008_cpu_standby_sz);
+
+        /*do suspend */
+        pnx4008_cpu_standby_ptr = (void *)SRAM_VA;
+        pnx4008_cpu_standby_ptr();
+
+        /*restoring portion of SRAM that was used by suspend function */
+        memcpy((void *)SRAM_VA, saved_sram, pnx4008_cpu_standby_sz);
+
+        clk_enable(pll4_clk);
+
+        local_fiq_enable();
+        local_irq_enable();
+}
+
+static inline void pnx4008_suspend(void)
+{
+        void (*pnx4008_cpu_suspend_ptr) (void);
+
+        local_irq_disable();
+        local_fiq_disable();
+
+        clk_disable(pll4_clk);
+
+        __raw_writel(0xffffffff, START_INT_RSR_REG(SE_PIN_BASE_INT));
+        __raw_writel(0xffffffff, START_INT_RSR_REG(SE_INT_BASE_INT));
+
+        /*saving portion of SRAM to be used by suspend function. */
+        memcpy(saved_sram, (void *)SRAM_VA, pnx4008_cpu_suspend_sz);
+
+        /*make sure SRAM copy gets physically written into SDRAM.
+           SDRAM will be placed into self-refresh during power down */
+        flush_cache_all();
+
+        /*copy suspend function into SRAM */
+        memcpy((void *)SRAM_VA, pnx4008_cpu_suspend, pnx4008_cpu_suspend_sz);
+
+        /*do suspend */
+        pnx4008_cpu_suspend_ptr = (void *)SRAM_VA;
+        pnx4008_cpu_suspend_ptr();
+
+        /*restoring portion of SRAM that was used by suspend function */
+        memcpy((void *)SRAM_VA, saved_sram, pnx4008_cpu_suspend_sz);
+
+        clk_enable(pll4_clk);
+
+        local_fiq_enable();
+        local_irq_enable();
+}
+
+static int pnx4008_pm_enter(suspend_state_t state)
+{
+        switch (state) {
+        case PM_SUSPEND_STANDBY:
+                pnx4008_standby();
+                break;
+        case PM_SUSPEND_MEM:
+                pnx4008_suspend();
+                break;
+        case PM_SUSPEND_DISK:
+                return -ENOTSUPP;
+        default:
+                return -EINVAL;
+        }
+        return 0;
+}
+
+/*
+ * Called after processes are frozen, but before we shut down devices.
+ */
+static int pnx4008_pm_prepare(suspend_state_t state)
+{
+        switch (state) {
+        case PM_SUSPEND_STANDBY:
+        case PM_SUSPEND_MEM:
+                break;
+
+        case PM_SUSPEND_DISK:
+                return -ENOTSUPP;
+                break;
+
+        default:
+                return -EINVAL;
+                break;
+        }
+        return 0;
+}
+
+/*
+ * Called after devices are re-setup, but before processes are thawed.
+ */
+static int pnx4008_pm_finish(suspend_state_t state)
+{
+        return 0;
+}
+
+/*
+ * Set to PM_DISK_FIRMWARE so we can quickly veto suspend-to-disk.
+ */
+static struct pm_ops pnx4008_pm_ops = {
+        .prepare = pnx4008_pm_prepare,
+        .enter = pnx4008_pm_enter,
+        .finish = pnx4008_pm_finish,
+};
+
+static int __init pnx4008_pm_init(void)
+{
+        u32 sram_size_to_allocate;
+
+        pll4_clk = clk_get(0, "ck_pll4");
+        if (IS_ERR(pll4_clk)) {
+                printk(KERN_ERR
+                       "PM Suspend cannot acquire ARM(PLL4) clock control\n");
+                return PTR_ERR(pll4_clk);
+        }
+
+        if (pnx4008_cpu_standby_sz > pnx4008_cpu_suspend_sz)
+                sram_size_to_allocate = pnx4008_cpu_standby_sz;
+        else
+                sram_size_to_allocate = pnx4008_cpu_suspend_sz;
+
+        saved_sram = kmalloc(sram_size_to_allocate, GFP_ATOMIC);
+        if (!saved_sram) {
+                printk(KERN_ERR
+                       "PM Suspend: cannot allocate memory to save portion of SRAM\n");
+                clk_put(pll4_clk);
+                return -ENOMEM;
+        }
+
+        pm_set_ops(&pnx4008_pm_ops);
+        return 0;
+}
+
+late_initcall(pnx4008_pm_init);