Merge branch 'pci/controller/dwc-rcar-gen4'

- When MSI is enabled but iMSI-RX is not used, configure AXIINTC to allow
  GIT ITS to handle MSI (Marek Vasut)

- Refactor GIC600 implementation to make it easier to add platforms that
  only support 32-bit addressing (Marek Vasut)

- Add Renesas R-Car Gen4 S4/V4H/V4M to the list of GIC600 integrations that
  only support 32-bit addressing (Marek Vasut)

* pci/controller/dwc-rcar-gen4:
  irqchip/gic-v3: Add Renesas R-Car Gen4 erratum workaround
  irqchip/gic-v3: Refactor GIC600 limited to 32bit PA erratum handling
  PCI: rcar-gen4: Configure AXIINTC if iMSI-RX is not used
  PCI: dwc: Move iMSI-RX check before calling 'pp->ops->init()'

3 files changed, 121 insertions, 11 deletions

diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
index 49a7a2c50ca1..3260d916110b 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -346,7 +346,7 @@ config PCIE_RCAR_GEN4
 
 config PCIE_RCAR_GEN4_HOST
 	tristate "Renesas R-Car Gen4 PCIe controller (host mode)"
-	depends on ARCH_RENESAS || COMPILE_TEST
+	depends on ARM64 && (ARCH_RENESAS || COMPILE_TEST)
 	depends on PCI_MSI
 	select PCIE_DW_HOST
 	select PCIE_RCAR_GEN4
@@ -357,7 +357,7 @@ config PCIE_RCAR_GEN4_HOST
 
 config PCIE_RCAR_GEN4_EP
 	tristate "Renesas R-Car Gen4 PCIe controller (endpoint mode)"
-	depends on ARCH_RENESAS || COMPILE_TEST
+	depends on ARM64 && (ARCH_RENESAS || COMPILE_TEST)
 	depends on PCI_ENDPOINT
 	select PCIE_DW_EP
 	select PCIE_RCAR_GEN4
diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index 06722259d2e3..f5a38e6fd8d7 100644
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -587,6 +587,12 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
 	if (ret)
 		return ret;
 
+	if (pci_msi_enabled()) {
+		pp->use_imsi_rx = !(pp->ops->msi_init ||
+				    of_property_present(np, "msi-parent") ||
+				    of_property_present(np, "msi-map"));
+	}
+
 	if (pp->ops->init) {
 		ret = pp->ops->init(pp);
 		if (ret)
@@ -594,10 +600,6 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
 	}
 
 	if (pci_msi_enabled()) {
-		pp->use_imsi_rx = !(pp->ops->msi_init ||
-				     of_property_present(np, "msi-parent") ||
-				     of_property_present(np, "msi-map"));
-
 		/*
 		 * For the use_imsi_rx case the default assignment is handled
 		 * in the dw_pcie_msi_host_init().
diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
index 8b03c42f8c84..5f7211b91ee5 100644
--- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
+++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
@@ -13,8 +13,11 @@
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
+#include <linux/irqchip/arm-gic-v3.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
@@ -31,6 +34,10 @@
 #define DEVICE_TYPE_RC		BIT(4)
 #define BIFUR_MOD_SET_ON	BIT(0)
 
+/* MSI Capability */
+#define MSICAP0			0x0050
+#define MSICAP0_MSIE		BIT(16)
+
 /* PCIe Interrupt Status 0 */
 #define PCIEINTSTS0		0x0084
 
@@ -55,6 +62,14 @@
 #define APP_HOLD_PHY_RST	BIT(16)
 #define APP_LTSSM_ENABLE	BIT(0)
 
+/* INTC address */
+#define AXIINTCADDR		0x0a00
+
+/* INTC control & mask */
+#define AXIINTCCONT		0x0a04
+#define INTC_EN			BIT(31)
+#define INTC_MASK		GENMASK(11, 3)
+
 /* PCIe Power Management Control */
 #define PCIEPWRMNGCTRL		0x0070
 #define APP_CLK_REQ_N		BIT(11)
@@ -305,13 +320,103 @@ static struct rcar_gen4_pcie *rcar_gen4_pcie_alloc(struct platform_device *pdev)
 	return rcar;
 }
 
+static int rcar_gen4_pcie_host_msi_addr(struct dw_pcie_rp *pp, u32 *msi_addr)
+{
+	struct dw_pcie *dw = to_dw_pcie_from_pp(pp);
+	struct device_node *msi_node = NULL;
+	struct device *dev = dw->dev;
+	struct resource res;
+	u64 addr;
+	int ret;
+
+	/*
+	 * Either the "msi-parent" or the "msi-map" phandle needs to exist
+	 * to obtain the MSI node.
+	 */
+	of_msi_xlate(dev, &msi_node, 0);
+	if (!msi_node)
+		return -ENODEV;
+
+	/* Check if "msi-parent" or the "msi-map" points to ARM GICv3 ITS. */
+	if (!of_device_is_compatible(msi_node, "arm,gic-v3-its"))
+		return dev_err_probe(dev, -ENODEV, "Compatible MSI controller not found\n");
+
+	/* Derive GITS_TRANSLATER address from GICv3 */
+	ret = of_address_to_resource(msi_node, 0, &res);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "MSI controller resources not obtained\n");
+
+	addr = res.start + GITS_TRANSLATER;
+	if (addr >= SZ_4G)
+		return dev_err_probe(dev, -EINVAL, "MSI controller address above 32bit range\n");
+
+	*msi_addr = addr;
+	return 0;
+}
+
+static int rcar_gen4_pcie_host_msi_init(struct dw_pcie_rp *pp)
+{
+	struct dw_pcie *dw = to_dw_pcie_from_pp(pp);
+	struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw);
+	u32 val;
+	int ret;
+
+	/* Make sure MSICAP0 MSIE is configured. */
+	val = dw_pcie_readl_dbi(dw, MSICAP0);
+	if (pci_msi_enabled())
+		val |= MSICAP0_MSIE;
+	else
+		val &= ~MSICAP0_MSIE;
+	dw_pcie_writel_dbi(dw, MSICAP0, val);
+
+	if (!pci_msi_enabled() || pp->use_imsi_rx) {
+		/* Clear AXIINTC mapping. */
+		writel(0, rcar->base + AXIINTCADDR);
+		writel(0, rcar->base + AXIINTCCONT);
+	} else {
+		ret = rcar_gen4_pcie_host_msi_addr(pp, &val);
+		if (ret)
+			goto err;
+
+		/* Point AXIINTC to GIC ITS and enable. */
+		writel(val, rcar->base + AXIINTCADDR);
+		writel(INTC_EN | INTC_MASK, rcar->base + AXIINTCCONT);
+	}
+
+	/* Configure MSI interrupt signal */
+	val = readl(rcar->base + PCIEINTSTS0EN);
+	if (pci_msi_enabled())
+		val |= MSI_CTRL_INT;
+	else
+		val &= ~MSI_CTRL_INT;
+	writel(val, rcar->base + PCIEINTSTS0EN);
+
+	return 0;
+
+err:
+	/* Deconfigure MSICAP0 MSIE. */
+	val = dw_pcie_readl_dbi(dw, MSICAP0);
+	val &= ~MSICAP0_MSIE;
+	dw_pcie_writel_dbi(dw, MSICAP0, val);
+
+	/* Clear AXIINTC mapping. */
+	writel(0, rcar->base + AXIINTCADDR);
+	writel(0, rcar->base + AXIINTCCONT);
+
+	/* Deconfigure MSI interrupt signal */
+	val = readl(rcar->base + PCIEINTSTS0EN);
+	val &= ~MSI_CTRL_INT;
+	writel(val, rcar->base + PCIEINTSTS0EN);
+
+	return ret;
+}
+
 /* Host mode */
 static int rcar_gen4_pcie_host_init(struct dw_pcie_rp *pp)
 {
 	struct dw_pcie *dw = to_dw_pcie_from_pp(pp);
 	struct rcar_gen4_pcie *rcar = to_rcar_gen4_pcie(dw);
 	int ret;
-	u32 val;
 
 	gpiod_set_value_cansleep(dw->pe_rst, 1);
 
@@ -328,16 +433,19 @@ static int rcar_gen4_pcie_host_init(struct dw_pcie_rp *pp)
 	dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_0, 0x0);
 	dw_pcie_writel_dbi2(dw, PCI_BASE_ADDRESS_1, 0x0);
 
-	/* Enable MSI interrupt signal */
-	val = readl(rcar->base + PCIEINTSTS0EN);
-	val |= MSI_CTRL_INT;
-	writel(val, rcar->base + PCIEINTSTS0EN);
+	ret = rcar_gen4_pcie_host_msi_init(pp);
+	if (ret)
+		goto err;
 
 	msleep(PCIE_T_PVPERL_MS);	/* pe_rst requires 100msec delay */
 
 	gpiod_set_value_cansleep(dw->pe_rst, 0);
 
 	return 0;
+
+err:
+	rcar_gen4_pcie_common_deinit(rcar);
+	return ret;
 }
 
 static void rcar_gen4_pcie_host_deinit(struct dw_pcie_rp *pp)