[PATCH v3 12/13] PCI: apple: Abstract register offsets via a SoC-specific structure

[Marc Zyngier <maz@kernel.org>]

From: Hector Martin <marcan@marcan.st>

Newer versions of the Apple PCIe block have a bunch of small, but
annoying differences.

In order to embrace this diversity of implementations, move the
currently hardcoded offsets into a hw_info structure. Future SoCs
will provide their own structure describing the applicable offsets.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Acked-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Tested-by: Janne Grunau <j@jannau.net>
Signed-off-by: Hector Martin <marcan@marcan.st>
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
[maz: split from original patch to only address T8103]
Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 drivers/pci/controller/pcie-apple.c | 89 +++++++++++++++++++++++------
 1 file changed, 72 insertions(+), 17 deletions(-)

diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c
index 505adf64bd66d..847cba753d28d 100644
--- a/drivers/pci/controller/pcie-apple.c
+++ b/drivers/pci/controller/pcie-apple.c
@@ -18,6 +18,7 @@
  * Author: Marc Zyngier <maz@kernel.org>
  */
 
+#include <linux/bitfield.h>
 #include <linux/gpio/consumer.h>
 #include <linux/kernel.h>
 #include <linux/iopoll.h>
@@ -29,6 +30,7 @@
 #include <linux/of_irq.h>
 #include <linux/pci-ecam.h>
 
+/* T8103 (original M1) and related SoCs */
 #define CORE_RC_PHYIF_CTL		0x00024
 #define   CORE_RC_PHYIF_CTL_RUN		BIT(0)
 #define CORE_RC_PHYIF_STAT		0x00028
@@ -104,7 +106,7 @@
 #define   PORT_REFCLK_CGDIS		BIT(8)
 #define PORT_PERST			0x00814
 #define   PORT_PERST_OFF		BIT(0)
-#define PORT_RID2SID(i16)		(0x00828 + 4 * (i16))
+#define PORT_RID2SID			0x00828
 #define   PORT_RID2SID_VALID		BIT(31)
 #define   PORT_RID2SID_SID_SHIFT	16
 #define   PORT_RID2SID_BUS_SHIFT	8
@@ -122,7 +124,8 @@
 #define   PORT_TUNSTAT_PERST_ACK_PEND	BIT(1)
 #define PORT_PREFMEM_ENABLE		0x00994
 
-#define MAX_RID2SID			64
+#define PORT_MSIMAP_ENABLE	BIT(31)
+#define PORT_MSIMAP_TARGET	GENMASK(7, 0)
 
 /*
  * The doorbell address is set to 0xfffff000, which by convention
@@ -133,10 +136,33 @@
  */
 #define DOORBELL_ADDR		CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR
 
+struct hw_info {
+	u32 phy_lane_ctl;
+	u32 port_msiaddr;
+	u32 port_msiaddr_hi;
+	u32 port_refclk;
+	u32 port_perst;
+	u32 port_rid2sid;
+	u32 port_msimap;
+	u32 max_rid2sid;
+};
+
+static const struct hw_info t8103_hw = {
+	.phy_lane_ctl		= PHY_LANE_CTL,
+	.port_msiaddr		= PORT_MSIADDR,
+	.port_msiaddr_hi	= 0,
+	.port_refclk		= PORT_REFCLK,
+	.port_perst		= PORT_PERST,
+	.port_rid2sid		= PORT_RID2SID,
+	.port_msimap		= 0,
+	.max_rid2sid		= 64,
+};
+
 struct apple_pcie {
 	struct mutex		lock;
 	struct device		*dev;
 	void __iomem            *base;
+	const struct hw_info	*hw;
 	struct irq_domain	*domain;
 	unsigned long		*bitmap;
 	struct list_head	ports;
@@ -380,7 +406,9 @@ static void apple_port_irq_handler(struct irq_desc *desc)
 static int apple_pcie_port_setup_irq(struct apple_pcie_port *port)
 {
 	struct fwnode_handle *fwnode = &port->np->fwnode;
+	struct apple_pcie *pcie = port->pcie;
 	unsigned int irq;
+	u32 val = 0;
 
 	/* FIXME: consider moving each interrupt under each port */
 	irq = irq_of_parse_and_map(to_of_node(dev_fwnode(port->pcie->dev)),
@@ -402,13 +430,23 @@ static int apple_pcie_port_setup_irq(struct apple_pcie_port *port)
 
 	/* Configure MSI base address */
 	BUILD_BUG_ON(upper_32_bits(DOORBELL_ADDR));
-	writel_relaxed(lower_32_bits(DOORBELL_ADDR), port->base + PORT_MSIADDR);
+	writel_relaxed(lower_32_bits(DOORBELL_ADDR),
+		       port->base + pcie->hw->port_msiaddr);
+	if (pcie->hw->port_msiaddr_hi)
+		writel_relaxed(0, port->base + pcie->hw->port_msiaddr_hi);
 
 	/* Enable MSIs, shared between all ports */
-	writel_relaxed(0, port->base + PORT_MSIBASE);
-	writel_relaxed((ilog2(port->pcie->nvecs) << PORT_MSICFG_L2MSINUM_SHIFT) |
-		       PORT_MSICFG_EN, port->base + PORT_MSICFG);
+	if (pcie->hw->port_msimap) {
+		for (int i = 0; i < pcie->nvecs; i++)
+			writel_relaxed(FIELD_PREP(PORT_MSIMAP_TARGET, i) |
+				       PORT_MSIMAP_ENABLE,
+				       port->base + pcie->hw->port_msimap + 4 * i);
+	} else {
+		writel_relaxed(0, port->base + PORT_MSIBASE);
+		val = ilog2(pcie->nvecs) << PORT_MSICFG_L2MSINUM_SHIFT;
+	}
 
+	writel_relaxed(val | PORT_MSICFG_EN, port->base + PORT_MSICFG);
 	return 0;
 }
 
@@ -475,7 +513,9 @@ static int apple_pcie_setup_refclk(struct apple_pcie *pcie,
 	u32 stat;
 	int res;
 
-	rmw_set(PHY_LANE_CTL_CFGACC, port->phy + PHY_LANE_CTL);
+	if (pcie->hw->phy_lane_ctl)
+		rmw_set(PHY_LANE_CTL_CFGACC, port->phy + pcie->hw->phy_lane_ctl);
+
 	rmw_set(PHY_LANE_CFG_REFCLK0REQ, port->phy + PHY_LANE_CFG);
 
 	res = readl_relaxed_poll_timeout(port->phy + PHY_LANE_CFG,
@@ -492,20 +532,28 @@ static int apple_pcie_setup_refclk(struct apple_pcie *pcie,
 	if (res < 0)
 		return res;
 
-	rmw_clear(PHY_LANE_CTL_CFGACC, port->phy + PHY_LANE_CTL);
+	if (pcie->hw->phy_lane_ctl)
+		rmw_clear(PHY_LANE_CTL_CFGACC, port->phy + pcie->hw->phy_lane_ctl);
 
 	rmw_set(PHY_LANE_CFG_REFCLKEN, port->phy + PHY_LANE_CFG);
-	rmw_set(PORT_REFCLK_EN, port->base + PORT_REFCLK);
+
+	if (pcie->hw->port_refclk)
+		rmw_set(PORT_REFCLK_EN, port->base + pcie->hw->port_refclk);
 
 	return 0;
 }
 
+static void __iomem *port_rid2sid_addr(struct apple_pcie_port *port, int idx)
+{
+	return port->base + port->pcie->hw->port_rid2sid + 4 * idx;
+}
+
 static u32 apple_pcie_rid2sid_write(struct apple_pcie_port *port,
 				    int idx, u32 val)
 {
-	writel_relaxed(val, port->base + PORT_RID2SID(idx));
+	writel_relaxed(val, port_rid2sid_addr(port, idx));
 	/* Read back to ensure completion of the write */
-	return readl_relaxed(port->base + PORT_RID2SID(idx));
+	return readl_relaxed(port_rid2sid_addr(port, idx));
 }
 
 static int apple_pcie_setup_port(struct apple_pcie *pcie,
@@ -528,7 +576,7 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie,
 	if (!port)
 		return -ENOMEM;
 
-	port->sid_map = devm_bitmap_zalloc(pcie->dev, MAX_RID2SID, GFP_KERNEL);
+	port->sid_map = devm_bitmap_zalloc(pcie->dev, pcie->hw->max_rid2sid, GFP_KERNEL);
 	if (!port->sid_map)
 		return -ENOMEM;
 
@@ -572,7 +620,7 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie,
 	usleep_range(100, 200);
 
 	/* Deassert PERST# */
-	rmw_set(PORT_PERST_OFF, port->base + PORT_PERST);
+	rmw_set(PORT_PERST_OFF, port->base + pcie->hw->port_perst);
 	gpiod_set_value_cansleep(reset, 0);
 
 	/* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
@@ -585,7 +633,11 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie,
 		return ret;
 	}
 
-	rmw_clear(PORT_REFCLK_CGDIS, port->base + PORT_REFCLK);
+	if (pcie->hw->port_refclk)
+		rmw_clear(PORT_REFCLK_CGDIS, port->base + pcie->hw->port_refclk);
+	else
+		rmw_set(PHY_LANE_CFG_REFCLKCGEN, port->phy + PHY_LANE_CFG);
+
 	rmw_clear(PORT_APPCLK_CGDIS, port->base + PORT_APPCLK);
 
 	ret = apple_pcie_port_setup_irq(port);
@@ -593,7 +645,7 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie,
 		return ret;
 
 	/* Reset all RID/SID mappings, and check for RAZ/WI registers */
-	for (i = 0; i < MAX_RID2SID; i++) {
+	for (i = 0; i < pcie->hw->max_rid2sid; i++) {
 		if (apple_pcie_rid2sid_write(port, i, 0xbad1d) != 0xbad1d)
 			break;
 		apple_pcie_rid2sid_write(port, i, 0);
@@ -741,7 +793,7 @@ static void apple_pcie_disable_device(struct pci_host_bridge *bridge, struct pci
 	for_each_set_bit(idx, port->sid_map, port->sid_map_sz) {
 		u32 val;
 
-		val = readl_relaxed(port->base + PORT_RID2SID(idx));
+		val = readl_relaxed(port_rid2sid_addr(port, idx));
 		if ((val & 0xffff) == rid) {
 			apple_pcie_rid2sid_write(port, idx, 0);
 			bitmap_release_region(port->sid_map, idx, 0);
@@ -794,6 +846,9 @@ static int apple_pcie_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	pcie->dev = dev;
+	pcie->hw = of_device_get_match_data(dev);
+	if (!pcie->hw)
+		return -ENODEV;
 	pcie->base = devm_platform_ioremap_resource(pdev, 1);
 	if (IS_ERR(pcie->base))
 		return PTR_ERR(pcie->base);
@@ -810,7 +865,7 @@ static int apple_pcie_probe(struct platform_device *pdev)
 }
 
 static const struct of_device_id apple_pcie_of_match[] = {
-	{ .compatible = "apple,pcie" },
+	{ .compatible = "apple,pcie",		.data = &t8103_hw },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, apple_pcie_of_match);
-- 
2.39.2