fsl/pci: The new pci suspend/resume implementation

If we do nothing in suspend/resume, some platform PCIe ip-block
can't guarantee the link back to L0 state from sleep, then, when
we read the EP device will hang. Only we send pme turnoff message
in pci controller suspend, and send pme exit message in resume, the
link state will be normal.

When we send pme turnoff message in pci controller suspend, the
links will into l2/l3 ready, then, host cannot communicate with
ep device, but pci-driver will call back EP device to save them
state. So we need to change platform_driver->suspend/resume to
syscore->suspend/resume.

So the new suspend/resume implementation, send pme turnoff message
in suspend, and send pme exit message in resume. And add a PME handler,
to response PME & message interrupt.

Change platform_driver->suspend/resume to syscore->suspend/resume.
pci-driver will call back EP device, to save EP state in
pci_pm_suspend_noirq, so we need to keep the link, until
pci_pm_suspend_noirq finish.

Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>

2 files changed, 154 insertions, 24 deletions

diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
index 8cdd3448257..3f415e252ea 100644
--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c
@@ -22,10 +22,13 @@
 #include <linux/delay.h>
 #include <linux/string.h>
 #include <linux/init.h>
+#include <linux/interrupt.h>
 #include <linux/bootmem.h>
 #include <linux/memblock.h>
 #include <linux/log2.h>
 #include <linux/slab.h>
+#include <linux/suspend.h>
+#include <linux/syscore_ops.h>
 #include <linux/uaccess.h>
 
 #include <asm/io.h>
@@ -1094,55 +1097,171 @@ void fsl_pci_assign_primary(void)
 	}
 }
 
-static int fsl_pci_probe(struct platform_device *pdev)
+#ifdef CONFIG_PM_SLEEP
+static irqreturn_t fsl_pci_pme_handle(int irq, void *dev_id)
 {
-	int ret;
-	struct device_node *node;
+	struct pci_controller *hose = dev_id;
+	struct ccsr_pci __iomem *pci = hose->private_data;
+	u32 dr;
 
-	node = pdev->dev.of_node;
-	ret = fsl_add_bridge(pdev, fsl_pci_primary == node);
+	dr = in_be32(&pci->pex_pme_mes_dr);
+	if (!dr)
+		return IRQ_NONE;
 
-	mpc85xx_pci_err_probe(pdev);
+	out_be32(&pci->pex_pme_mes_dr, dr);
 
-	return 0;
+	return IRQ_HANDLED;
 }
 
-#ifdef CONFIG_PM
-static int fsl_pci_resume(struct device *dev)
+static int fsl_pci_pme_probe(struct pci_controller *hose)
 {
-	struct pci_controller *hose;
-	struct resource pci_rsrc;
+	struct ccsr_pci __iomem *pci;
+	struct pci_dev *dev;
+	int pme_irq;
+	int res;
+	u16 pms;
 
-	hose = pci_find_hose_for_OF_device(dev->of_node);
-	if (!hose)
-		return -ENODEV;
+	/* Get hose's pci_dev */
+	dev = list_first_entry(&hose->bus->devices, typeof(*dev), bus_list);
+
+	/* PME Disable */
+	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pms);
+	pms &= ~PCI_PM_CTRL_PME_ENABLE;
+	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pms);
+
+	pme_irq = irq_of_parse_and_map(hose->dn, 0);
+	if (!pme_irq) {
+		dev_err(&dev->dev, "Failed to map PME interrupt.\n");
+
+		return -ENXIO;
+	}
+
+	res = devm_request_irq(hose->parent, pme_irq,
+			fsl_pci_pme_handle,
+			IRQF_SHARED,
+			"[PCI] PME", hose);
+	if (res < 0) {
+		dev_err(&dev->dev, "Unable to requiest irq %d for PME\n", pme_irq);
+		irq_dispose_mapping(pme_irq);
 
-	if (of_address_to_resource(dev->of_node, 0, &pci_rsrc)) {
-		dev_err(dev, "Get pci register base failed.");
 		return -ENODEV;
 	}
 
-	setup_pci_atmu(hose);
+	pci = hose->private_data;
+
+	/* Enable PTOD, ENL23D & EXL23D */
+	out_be32(&pci->pex_pme_mes_disr, 0);
+	setbits32(&pci->pex_pme_mes_disr,
+		  PME_DISR_EN_PTOD | PME_DISR_EN_ENL23D | PME_DISR_EN_EXL23D);
+
+	out_be32(&pci->pex_pme_mes_ier, 0);
+	setbits32(&pci->pex_pme_mes_ier,
+		  PME_DISR_EN_PTOD | PME_DISR_EN_ENL23D | PME_DISR_EN_EXL23D);
+
+	/* PME Enable */
+	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pms);
+	pms |= PCI_PM_CTRL_PME_ENABLE;
+	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pms);
 
 	return 0;
 }
 
-static const struct dev_pm_ops pci_pm_ops = {
-	.resume = fsl_pci_resume,
-};
+static void send_pme_turnoff_message(struct pci_controller *hose)
+{
+	struct ccsr_pci __iomem *pci = hose->private_data;
+	u32 dr;
+	int i;
 
-#define PCI_PM_OPS (&pci_pm_ops)
+	/* Send PME_Turn_Off Message Request */
+	setbits32(&pci->pex_pmcr, PEX_PMCR_PTOMR);
 
-#else
+	/* Wait trun off done */
+	for (i = 0; i < 150; i++) {
+		dr = in_be32(&pci->pex_pme_mes_dr);
+		if (dr) {
+			out_be32(&pci->pex_pme_mes_dr, dr);
+			break;
+		}
 
-#define PCI_PM_OPS NULL
+		udelay(1000);
+	}
+}
 
+static void fsl_pci_syscore_do_suspend(struct pci_controller *hose)
+{
+	send_pme_turnoff_message(hose);
+}
+
+static int fsl_pci_syscore_suspend(void)
+{
+	struct pci_controller *hose, *tmp;
+
+	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
+		fsl_pci_syscore_do_suspend(hose);
+
+	return 0;
+}
+
+static void fsl_pci_syscore_do_resume(struct pci_controller *hose)
+{
+	struct ccsr_pci __iomem *pci = hose->private_data;
+	u32 dr;
+	int i;
+
+	/* Send Exit L2 State Message */
+	setbits32(&pci->pex_pmcr, PEX_PMCR_EXL2S);
+
+	/* Wait exit done */
+	for (i = 0; i < 150; i++) {
+		dr = in_be32(&pci->pex_pme_mes_dr);
+		if (dr) {
+			out_be32(&pci->pex_pme_mes_dr, dr);
+			break;
+		}
+
+		udelay(1000);
+	}
+
+	setup_pci_atmu(hose);
+}
+
+static void fsl_pci_syscore_resume(void)
+{
+	struct pci_controller *hose, *tmp;
+
+	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
+		fsl_pci_syscore_do_resume(hose);
+}
+
+static struct syscore_ops pci_syscore_pm_ops = {
+	.suspend = fsl_pci_syscore_suspend,
+	.resume = fsl_pci_syscore_resume,
+};
 #endif
 
+void fsl_pcibios_fixup_phb(struct pci_controller *phb)
+{
+#ifdef CONFIG_PM_SLEEP
+	fsl_pci_pme_probe(phb);
+#endif
+}
+
+static int fsl_pci_probe(struct platform_device *pdev)
+{
+	struct device_node *node;
+	int ret;
+
+	node = pdev->dev.of_node;
+	ret = fsl_add_bridge(pdev, fsl_pci_primary == node);
+
+	mpc85xx_pci_err_probe(pdev);
+
+	return 0;
+}
+
 static struct platform_driver fsl_pci_driver = {
 	.driver = {
 		.name = "fsl-pci",
-		.pm = PCI_PM_OPS,
 		.of_match_table = pci_ids,
 	},
 	.probe = fsl_pci_probe,
@@ -1150,6 +1269,9 @@ static struct platform_driver fsl_pci_driver = {
 
 static int __init fsl_pci_init(void)
 {
+#ifdef CONFIG_PM_SLEEP
+	register_syscore_ops(&pci_syscore_pm_ops);
+#endif
 	return platform_driver_register(&fsl_pci_driver);
 }
 arch_initcall(fsl_pci_init);
diff --git a/arch/powerpc/sysdev/fsl_pci.h b/arch/powerpc/sysdev/fsl_pci.h
index 8d455df5847..c1cec771d5e 100644
--- a/arch/powerpc/sysdev/fsl_pci.h
+++ b/arch/powerpc/sysdev/fsl_pci.h
@@ -32,6 +32,13 @@ struct platform_device;
 #define PIWAR_WRITE_SNOOP	0x00005000
 #define PIWAR_SZ_MASK          0x0000003f
 
+#define PEX_PMCR_PTOMR		0x1
+#define PEX_PMCR_EXL2S		0x2
+
+#define PME_DISR_EN_PTOD	0x00008000
+#define PME_DISR_EN_ENL23D	0x00002000
+#define PME_DISR_EN_EXL23D	0x00001000
+
 /* PCI/PCI Express outbound window reg */
 struct pci_outbound_window_regs {
 	__be32	potar;	/* 0x.0 - Outbound translation address register */
@@ -111,6 +118,7 @@ struct ccsr_pci {
 
 extern int fsl_add_bridge(struct platform_device *pdev, int is_primary);
 extern void fsl_pcibios_fixup_bus(struct pci_bus *bus);
+extern void fsl_pcibios_fixup_phb(struct pci_controller *phb);
 extern int mpc83xx_add_bridge(struct device_node *dev);
 u64 fsl_pci_immrbar_base(struct pci_controller *hose);