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authorDaniel Drake <dsd@laptop.org>2011-06-25 17:34:11 +0100
committerH. Peter Anvin <hpa@linux.intel.com>2011-07-06 14:44:32 -0700
commit97c4cb71c18fe045a763ff6681a8ebbbbbec0b2b (patch)
tree66874802ab61cbf45c1d4d8d645b93e7600cdc0c /arch/x86/platform/olpc/olpc-xo1-pm.c
parenta3128588b3c6be634a9013a375903e0b55668f0a (diff)
downloadlinux-linaro-stable-97c4cb71c18fe045a763ff6681a8ebbbbbec0b2b.tar.gz
x86, olpc: Add XO-1 suspend/resume support
Add code needed for basic suspend/resume of the XO-1 laptop. Based on earlier work by Jordan Crouse, Andres Salomon, and others. This patch incorporates all earlier feedback from Thomas Gleixner. To clarify a certain point (now more obvious in the code itself): On resume, OpenFirmware returns execution to Linux in protected mode with a kernel-compatible GDT already set up. The changes and simplifications suggested have all been included. Signed-off-by: Daniel Drake <dsd@laptop.org> Link: http://lkml.kernel.org/r/1309019658-1712-5-git-send-email-dsd@laptop.org Acked-by: Andres Salomon <dilinger@queued.net> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/platform/olpc/olpc-xo1-pm.c')
-rw-r--r--arch/x86/platform/olpc/olpc-xo1-pm.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/arch/x86/platform/olpc/olpc-xo1-pm.c b/arch/x86/platform/olpc/olpc-xo1-pm.c
index a2a59d36824d..6f3855a5a2f7 100644
--- a/arch/x86/platform/olpc/olpc-xo1-pm.c
+++ b/arch/x86/platform/olpc/olpc-xo1-pm.c
@@ -16,6 +16,7 @@
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/mfd/core.h>
+#include <linux/suspend.h>
#include <asm/io.h>
#include <asm/olpc.h>
@@ -25,6 +26,85 @@
static unsigned long acpi_base;
static unsigned long pms_base;
+static u16 wakeup_mask = CS5536_PM_PWRBTN;
+
+static struct {
+ unsigned long address;
+ unsigned short segment;
+} ofw_bios_entry = { 0xF0000 + PAGE_OFFSET, __KERNEL_CS };
+
+/* Set bits in the wakeup mask */
+void olpc_xo1_pm_wakeup_set(u16 value)
+{
+ wakeup_mask |= value;
+}
+EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_set);
+
+/* Clear bits in the wakeup mask */
+void olpc_xo1_pm_wakeup_clear(u16 value)
+{
+ wakeup_mask &= ~value;
+}
+EXPORT_SYMBOL_GPL(olpc_xo1_pm_wakeup_clear);
+
+static int xo1_power_state_enter(suspend_state_t pm_state)
+{
+ unsigned long saved_sci_mask;
+ int r;
+
+ /* Only STR is supported */
+ if (pm_state != PM_SUSPEND_MEM)
+ return -EINVAL;
+
+ r = olpc_ec_cmd(EC_SET_SCI_INHIBIT, NULL, 0, NULL, 0);
+ if (r)
+ return r;
+
+ /*
+ * Save SCI mask (this gets lost since PM1_EN is used as a mask for
+ * wakeup events, which is not necessarily the same event set)
+ */
+ saved_sci_mask = inl(acpi_base + CS5536_PM1_STS);
+ saved_sci_mask &= 0xffff0000;
+
+ /* Save CPU state */
+ do_olpc_suspend_lowlevel();
+
+ /* Resume path starts here */
+
+ /* Restore SCI mask (using dword access to CS5536_PM1_EN) */
+ outl(saved_sci_mask, acpi_base + CS5536_PM1_STS);
+
+ /* Tell the EC to stop inhibiting SCIs */
+ olpc_ec_cmd(EC_SET_SCI_INHIBIT_RELEASE, NULL, 0, NULL, 0);
+
+ /*
+ * Tell the wireless module to restart USB communication.
+ * Must be done twice.
+ */
+ olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
+ olpc_ec_cmd(EC_WAKE_UP_WLAN, NULL, 0, NULL, 0);
+
+ return 0;
+}
+
+asmlinkage int xo1_do_sleep(u8 sleep_state)
+{
+ void *pgd_addr = __va(read_cr3());
+
+ /* Program wakeup mask (using dword access to CS5536_PM1_EN) */
+ outl(wakeup_mask << 16, acpi_base + CS5536_PM1_STS);
+
+ __asm__("movl %0,%%eax" : : "r" (pgd_addr));
+ __asm__("call *(%%edi); cld"
+ : : "D" (&ofw_bios_entry));
+ __asm__("movb $0x34, %al\n\t"
+ "outb %al, $0x70\n\t"
+ "movb $0x30, %al\n\t"
+ "outb %al, $0x71\n\t");
+ return 0;
+}
+
static void xo1_power_off(void)
{
printk(KERN_INFO "OLPC XO-1 power off sequence...\n");
@@ -43,6 +123,17 @@ static void xo1_power_off(void)
outl(0x00002000, acpi_base + CS5536_PM1_CNT);
}
+static int xo1_power_state_valid(suspend_state_t pm_state)
+{
+ /* suspend-to-RAM only */
+ return pm_state == PM_SUSPEND_MEM;
+}
+
+static const struct platform_suspend_ops xo1_suspend_ops = {
+ .valid = xo1_power_state_valid,
+ .enter = xo1_power_state_enter,
+};
+
static int __devinit xo1_pm_probe(struct platform_device *pdev)
{
struct resource *res;
@@ -68,6 +159,7 @@ static int __devinit xo1_pm_probe(struct platform_device *pdev)
/* If we have both addresses, we can override the poweroff hook */
if (pms_base && acpi_base) {
+ suspend_set_ops(&xo1_suspend_ops);
pm_power_off = xo1_power_off;
printk(KERN_INFO "OLPC XO-1 support registered\n");
}