MIPS: Alchemy: Fix PCI PM

Move PCI Controller PM to syscore_ops since the platform_driver PM methods
are called way too late on resume and far too early on suspend (after and
before PCI device resume/suspend).
This also allows to simplify wired entry management a bit.

Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3007/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 67 insertions, 70 deletions

diff --git a/arch/mips/pci/pci-alchemy.c b/arch/mips/pci/pci-alchemy.c
index b5ce041cdafb..b5eddf533c0b 100644
--- a/arch/mips/pci/pci-alchemy.c
+++ b/arch/mips/pci/pci-alchemy.c
@@ -13,6 +13,7 @@
 #include <linux/platform_device.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
+#include <linux/syscore_ops.h>
 #include <linux/vmalloc.h>
 
 #include <asm/mach-au1x00/au1000.h>
@@ -41,6 +42,12 @@ struct alchemy_pci_context {
         int (*board_pci_idsel)(unsigned int devsel, int assert);
 };
 
+/* for syscore_ops. There's only one PCI controller on Alchemy chips, so this
+ * should suffice for now.
+ */
+static struct alchemy_pci_context *__alchemy_pci_ctx;
+
+
 /* IO/MEM resources for PCI. Keep the memres in sync with __fixup_bigphys_addr
  * in arch/mips/alchemy/common/setup.c
  */
@@ -99,18 +106,6 @@ static int config_access(unsigned char access_type, struct pci_bus *bus,
                 return -1;
         }
 
-        /* YAMON on all db1xxx boards wipes the TLB and writes zero to C0_wired
-         * on resume, clearing our wired entry.  Unfortunately the ->resume()
-         * callback is called way way way too late (and ->suspend() too early)
-         * to have them destroy and recreate it.  Instead just test if c0_wired
-         * is now lower than the index we retrieved before suspending and then
-         * recreate the entry if necessary.  Of course this is totally bonkers
-         * and breaks as soon as someone else adds another wired entry somewhere
-         * else.  Anyone have any ideas how to handle this better?
-         */
-        if (unlikely(read_c0_wired() < ctx->wired_entry))
-                alchemy_pci_wired_entry(ctx);
-
         local_irq_save(flags);
         r = __raw_readl(ctx->regs + PCI_REG_STATCMD) & 0x0000ffff;
         r |= PCI_STATCMD_STATUS(0x2000);
@@ -304,6 +299,62 @@ static int alchemy_pci_def_idsel(unsigned int devsel, int assert)
         return 1;       /* success */
 }
 
+/* save PCI controller register contents. */
+static int alchemy_pci_suspend(void)
+{
+        struct alchemy_pci_context *ctx = __alchemy_pci_ctx;
+        if (!ctx)
+                return 0;
+
+        ctx->pm[0]  = __raw_readl(ctx->regs + PCI_REG_CMEM);
+        ctx->pm[1]  = __raw_readl(ctx->regs + PCI_REG_CONFIG) & 0x0009ffff;
+        ctx->pm[2]  = __raw_readl(ctx->regs + PCI_REG_B2BMASK_CCH);
+        ctx->pm[3]  = __raw_readl(ctx->regs + PCI_REG_B2BBASE0_VID);
+        ctx->pm[4]  = __raw_readl(ctx->regs + PCI_REG_B2BBASE1_SID);
+        ctx->pm[5]  = __raw_readl(ctx->regs + PCI_REG_MWMASK_DEV);
+        ctx->pm[6]  = __raw_readl(ctx->regs + PCI_REG_MWBASE_REV_CCL);
+        ctx->pm[7]  = __raw_readl(ctx->regs + PCI_REG_ID);
+        ctx->pm[8]  = __raw_readl(ctx->regs + PCI_REG_CLASSREV);
+        ctx->pm[9]  = __raw_readl(ctx->regs + PCI_REG_PARAM);
+        ctx->pm[10] = __raw_readl(ctx->regs + PCI_REG_MBAR);
+        ctx->pm[11] = __raw_readl(ctx->regs + PCI_REG_TIMEOUT);
+
+        return 0;
+}
+
+static void alchemy_pci_resume(void)
+{
+        struct alchemy_pci_context *ctx = __alchemy_pci_ctx;
+        if (!ctx)
+                return;
+
+        __raw_writel(ctx->pm[0],  ctx->regs + PCI_REG_CMEM);
+        __raw_writel(ctx->pm[2],  ctx->regs + PCI_REG_B2BMASK_CCH);
+        __raw_writel(ctx->pm[3],  ctx->regs + PCI_REG_B2BBASE0_VID);
+        __raw_writel(ctx->pm[4],  ctx->regs + PCI_REG_B2BBASE1_SID);
+        __raw_writel(ctx->pm[5],  ctx->regs + PCI_REG_MWMASK_DEV);
+        __raw_writel(ctx->pm[6],  ctx->regs + PCI_REG_MWBASE_REV_CCL);
+        __raw_writel(ctx->pm[7],  ctx->regs + PCI_REG_ID);
+        __raw_writel(ctx->pm[8],  ctx->regs + PCI_REG_CLASSREV);
+        __raw_writel(ctx->pm[9],  ctx->regs + PCI_REG_PARAM);
+        __raw_writel(ctx->pm[10], ctx->regs + PCI_REG_MBAR);
+        __raw_writel(ctx->pm[11], ctx->regs + PCI_REG_TIMEOUT);
+        wmb();
+        __raw_writel(ctx->pm[1],  ctx->regs + PCI_REG_CONFIG);
+        wmb();
+
+        /* YAMON on all db1xxx boards wipes the TLB and writes zero to C0_wired
+         * on resume, making it necessary to recreate it as soon as possible.
+         */
+        ctx->wired_entry = 8191;        /* impossibly high value */
+        alchemy_pci_wired_entry(ctx);   /* install it */
+}
+
+static struct syscore_ops alchemy_pci_pmops = {
+        .suspend        = alchemy_pci_suspend,
+        .resume         = alchemy_pci_resume,
+};
+
 static int __devinit alchemy_pci_probe(struct platform_device *pdev)
 {
         struct alchemy_pci_platdata *pd = pdev->dev.platform_data;
@@ -396,7 +447,8 @@ static int __devinit alchemy_pci_probe(struct platform_device *pdev)
                 ret = -ENOMEM;
                 goto out4;
         }
-        ctx->wired_entry = 8192;        /* impossibly high value */
+        ctx->wired_entry = 8191;        /* impossibly high value */
+        alchemy_pci_wired_entry(ctx);   /* install it */
 
         set_io_port_base((unsigned long)ctx->alchemy_pci_ctrl.io_map_base);
 
@@ -408,7 +460,9 @@ static int __devinit alchemy_pci_probe(struct platform_device *pdev)
         __raw_writel(val, ctx->regs + PCI_REG_CONFIG);
         wmb();
 
+        __alchemy_pci_ctx = ctx;
         platform_set_drvdata(pdev, ctx);
+        register_syscore_ops(&alchemy_pci_pmops);
         register_pci_controller(&ctx->alchemy_pci_ctrl);
 
         return 0;
@@ -425,68 +479,11 @@ out:
         return ret;
 }
 
-
-#ifdef CONFIG_PM
-/* save PCI controller register contents. */
-static int alchemy_pci_suspend(struct device *dev)
-{
-        struct alchemy_pci_context *ctx = dev_get_drvdata(dev);
-
-        ctx->pm[0]  = __raw_readl(ctx->regs + PCI_REG_CMEM);
-        ctx->pm[1]  = __raw_readl(ctx->regs + PCI_REG_CONFIG) & 0x0009ffff;
-        ctx->pm[2]  = __raw_readl(ctx->regs + PCI_REG_B2BMASK_CCH);
-        ctx->pm[3]  = __raw_readl(ctx->regs + PCI_REG_B2BBASE0_VID);
-        ctx->pm[4]  = __raw_readl(ctx->regs + PCI_REG_B2BBASE1_SID);
-        ctx->pm[5]  = __raw_readl(ctx->regs + PCI_REG_MWMASK_DEV);
-        ctx->pm[6]  = __raw_readl(ctx->regs + PCI_REG_MWBASE_REV_CCL);
-        ctx->pm[7]  = __raw_readl(ctx->regs + PCI_REG_ID);
-        ctx->pm[8]  = __raw_readl(ctx->regs + PCI_REG_CLASSREV);
-        ctx->pm[9]  = __raw_readl(ctx->regs + PCI_REG_PARAM);
-        ctx->pm[10] = __raw_readl(ctx->regs + PCI_REG_MBAR);
-        ctx->pm[11] = __raw_readl(ctx->regs + PCI_REG_TIMEOUT);
-
-        return 0;
-}
-
-static int alchemy_pci_resume(struct device *dev)
-{
-        struct alchemy_pci_context *ctx = dev_get_drvdata(dev);
-
-        __raw_writel(ctx->pm[0],  ctx->regs + PCI_REG_CMEM);
-        __raw_writel(ctx->pm[2],  ctx->regs + PCI_REG_B2BMASK_CCH);
-        __raw_writel(ctx->pm[3],  ctx->regs + PCI_REG_B2BBASE0_VID);
-        __raw_writel(ctx->pm[4],  ctx->regs + PCI_REG_B2BBASE1_SID);
-        __raw_writel(ctx->pm[5],  ctx->regs + PCI_REG_MWMASK_DEV);
-        __raw_writel(ctx->pm[6],  ctx->regs + PCI_REG_MWBASE_REV_CCL);
-        __raw_writel(ctx->pm[7],  ctx->regs + PCI_REG_ID);
-        __raw_writel(ctx->pm[8],  ctx->regs + PCI_REG_CLASSREV);
-        __raw_writel(ctx->pm[9],  ctx->regs + PCI_REG_PARAM);
-        __raw_writel(ctx->pm[10], ctx->regs + PCI_REG_MBAR);
-        __raw_writel(ctx->pm[11], ctx->regs + PCI_REG_TIMEOUT);
-        wmb();
-        __raw_writel(ctx->pm[1],  ctx->regs + PCI_REG_CONFIG);
-        wmb();
-
-        return 0;
-}
-
-static const struct dev_pm_ops alchemy_pci_pmops = {
-        .suspend        = alchemy_pci_suspend,
-        .resume         = alchemy_pci_resume,
-};
-
-#define ALCHEMY_PCICTL_PM       (&alchemy_pci_pmops)
-
-#else
-#define ALCHEMY_PCICTL_PM       NULL
-#endif
-
 static struct platform_driver alchemy_pcictl_driver = {
         .probe          = alchemy_pci_probe,
         .driver = {
                 .name   = "alchemy-pci",
                 .owner  = THIS_MODULE,
-                .pm     = ALCHEMY_PCICTL_PM,
         },
 };