[PATCH 3/3] pci: add BCM6328 PCIe controller support

Álvaro Fernández Rojas
2020-06-17T10:26:27Z

BCM6328 PCIe host controller is found on BCM6328, BCM6362 and BCM63268 SoCs.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---
drivers/pci/controller/Kconfig | 8 +
drivers/pci/controller/Makefile | 1 +
drivers/pci/controller/pcie-bcm6328.c | 346 ++++++++++++++++++++++++++
3 files changed, 355 insertions(+)
create mode 100644 drivers/pci/controller/pcie-bcm6328.c

diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index adddf21fa381..7e238c04764e 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -3,6 +3,14 @@
menu "PCI controller drivers"
depends on PCI

+config PCIE_BCM6328
+ bool "BCM6328 PCIe controller"
+ depends on BMIPS_GENERIC || COMPILE_TEST
+ depends on OF
+ help
+ Say Y here if you want support for the PCIe host controller found
+ on BCM6328, BCM6362 and BCM63268 SoCs.
+
config PCI_MVEBU
bool "Marvell EBU PCIe controller"
depends on ARCH_MVEBU || ARCH_DOVE || COMPILE_TEST
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index efd9733ead26..1c3e82575845 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -1,4 +1,5 @@
# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_PCIE_BCM6328) += pcie-bcm6328.o
obj-$(CONFIG_PCIE_CADENCE) += cadence/
obj-$(CONFIG_PCI_FTPCI100) += pci-ftpci100.o
obj-$(CONFIG_PCI_HYPERV) += pci-hyperv.o
diff --git a/drivers/pci/controller/pcie-bcm6328.c b/drivers/pci/controller/pcie-bcm6328.c
new file mode 100644
index 000000000000..5bd86b166336
--- /dev/null
+++ b/drivers/pci/controller/pcie-bcm6328.c
@@ -0,0 +1,346 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * BCM6328 PCIe Controller Driver
+ *
+ * Copyright (C) 2020 Álvaro Fernández Rojas <noltari@gmail.com>
+ * Copyright (C) 2015 Jonas Gorski <jonas.gorski@gmail.com>
+ * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_pci.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+#include "../pci.h"
+
+#define SERDES_PCIE_EN BIT(0)
+#define SERDES_PCIE_EXD_EN BIT(15)
+
+#define PCIE_BUS_BRIDGE 0
+#define PCIE_BUS_DEVICE 1
+
+#define PCIE_CONFIG2_REG 0x408
+#define CONFIG2_BAR1_SIZE_EN 1
+#define CONFIG2_BAR1_SIZE_MASK 0xf
+
+#define PCIE_IDVAL3_REG 0x43c
+#define IDVAL3_CLASS_CODE_MASK 0xffffff
+#define IDVAL3_SUBCLASS_SHIFT 8
+#define IDVAL3_CLASS_SHIFT 16
+
+#define PCIE_DLSTATUS_REG 0x1048
+#define DLSTATUS_PHYLINKUP BIT(13)
+
+#define PCIE_BRIDGE_OPT1_REG 0x2820
+#define OPT1_RD_BE_OPT_EN BIT(7)
+#define OPT1_RD_REPLY_BE_FIX_EN BIT(9)
+#define OPT1_PCIE_BRIDGE_HOLE_DET_EN BIT(11)
+#define OPT1_L1_INT_STATUS_MASK_POL BIT(12)
+
+#define PCIE_BRIDGE_OPT2_REG 0x2824
+#define OPT2_UBUS_UR_DECODE_DIS BIT(2)
+#define OPT2_TX_CREDIT_CHK_EN BIT(4)
+#define OPT2_CFG_TYPE1_BD_SEL BIT(7)
+#define OPT2_CFG_TYPE1_BUS_NO_SHIFT 16
+#define OPT2_CFG_TYPE1_BUS_NO_MASK (0xff << OPT2_CFG_TYPE1_BUS_NO_SHIFT)
+
+#define PCIE_BRIDGE_BAR0_BASEMASK_REG 0x2828
+#define BASEMASK_REMAP_EN BIT(0)
+#define BASEMASK_SWAP_EN BIT(1)
+#define BASEMASK_MASK_SHIFT 4
+#define BASEMASK_MASK_MASK (0xfff << BASEMASK_MASK_SHIFT)
+#define BASEMASK_BASE_SHIFT 20
+#define BASEMASK_BASE_MASK (0xfff << BASEMASK_BASE_SHIFT)
+
+#define PCIE_BRIDGE_BAR0_REBASE_ADDR_REG 0x282c
+#define REBASE_ADDR_BASE_SHIFT 20
+#define REBASE_ADDR_BASE_MASK (0xfff << REBASE_ADDR_BASE_SHIFT)
+
+#define PCIE_BRIDGE_RC_INT_MASK_REG 0x2854
+#define PCIE_RC_INT_A BIT(0)
+#define PCIE_RC_INT_B BIT(1)
+#define PCIE_RC_INT_C BIT(2)
+#define PCIE_RC_INT_D BIT(3)
+
+#define PCIE_DEVICE_OFFSET 0x8000
+
+struct bcm6328_pcie {
+ void __iomem *base;
+ struct regmap *serdes;
+ struct clk *clk;
+ struct reset_control *reset;
+ struct reset_control *reset_ext;
+ struct reset_control *reset_core;
+ struct reset_control *reset_hard;
+};
+
+static struct bcm6328_pcie bcm6328_pcie;
+
+/*
+ * swizzle 32bits data to return only the needed part
+ */
+static int postprocess_read(u32 data, int where, unsigned int size)
+{
+ u32 ret = 0;
+
+ switch (size) {
+ case 1:
+ ret = (data >> ((where & 3) << 3)) & 0xff;
+ break;
+ case 2:
+ ret = (data >> ((where & 3) << 3)) & 0xffff;
+ break;
+ case 4:
+ ret = data;
+ break;
+ }
+
+ return ret;
+}
+
+static int preprocess_write(u32 orig_data, u32 val, int where,
+ unsigned int size)
+{
+ u32 ret = 0;
+
+ switch (size) {
+ case 1:
+ ret = (orig_data & ~(0xff << ((where & 3) << 3))) |
+ (val << ((where & 3) << 3));
+ break;
+ case 2:
+ ret = (orig_data & ~(0xffff << ((where & 3) << 3))) |
+ (val << ((where & 3) << 3));
+ break;
+ case 4:
+ ret = val;
+ break;
+ }
+
+ return ret;
+}
+
+static int bcm6328_pcie_can_access(struct pci_bus *bus, int devfn)
+{
+ struct bcm6328_pcie *priv = &bcm6328_pcie;
+
+ switch (bus->number) {
+ case PCIE_BUS_BRIDGE:
+ return PCI_SLOT(devfn) == 0;
+ case PCIE_BUS_DEVICE:
+ if (PCI_SLOT(devfn) == 0)
+ return __raw_readl(priv->base + PCIE_DLSTATUS_REG)
+ & DLSTATUS_PHYLINKUP;
+ /* fall through */
+ default:
+ return false;
+ }
+}
+
+static int bcm6328_pcie_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *val)
+{
+ struct bcm6328_pcie *priv = &bcm6328_pcie;
+ u32 data;
+ u32 reg = where & ~3;
+
+ if (!bcm6328_pcie_can_access(bus, devfn))
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ if (bus->number == PCIE_BUS_DEVICE)
+ reg += PCIE_DEVICE_OFFSET;
+
+ data = __raw_readl(priv->base + reg);
+ *val = postprocess_read(data, where, size);
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int bcm6328_pcie_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 val)
+{
+ struct bcm6328_pcie *priv = &bcm6328_pcie;
+ u32 data;
+ u32 reg = where & ~3;
+
+ if (!bcm6328_pcie_can_access(bus, devfn))
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ if (bus->number == PCIE_BUS_DEVICE)
+ reg += PCIE_DEVICE_OFFSET;
+
+ data = __raw_readl(priv->base + reg);
+ data = preprocess_write(data, val, where, size);
+ __raw_writel(data, priv->base + reg);
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static struct pci_ops bcm6328_pcie_ops = {
+ .read = bcm6328_pcie_read,
+ .write = bcm6328_pcie_write,
+};
+
+static struct resource bcm6328_pcie_io_resource;
+static struct resource bcm6328_pcie_mem_resource;
+static struct resource bcm6328_pcie_busn_resource;
+
+static struct pci_controller bcm6328_pcie_controller = {
+ .pci_ops = &bcm6328_pcie_ops,
+ .io_resource = &bcm6328_pcie_io_resource,
+ .mem_resource = &bcm6328_pcie_mem_resource,
+ .busn_resource = &bcm6328_pcie_busn_resource,
+};
+
+static void bcm6328_pcie_reset(struct bcm6328_pcie *priv)
+{
+ regmap_write_bits(priv->serdes, 0,
+ SERDES_PCIE_EN | SERDES_PCIE_EXD_EN,
+ SERDES_PCIE_EN | SERDES_PCIE_EXD_EN);
+
+ reset_control_assert(priv->reset);
+ reset_control_assert(priv->reset_core);
+ reset_control_assert(priv->reset_ext);
+ if (priv->reset_hard) {
+ reset_control_assert(priv->reset_hard);
+ mdelay(10);
+ reset_control_deassert(priv->reset_hard);
+ }
+ mdelay(10);
+
+ reset_control_deassert(priv->reset_core);
+ reset_control_deassert(priv->reset);
+ mdelay(10);
+
+ reset_control_deassert(priv->reset_ext);
+ mdelay(200);
+}
+
+static void bcm6328_pcie_setup(struct bcm6328_pcie *priv)
+{
+ u32 val;
+
+ val = __raw_readl(priv->base + PCIE_BRIDGE_OPT1_REG);
+ val |= OPT1_RD_BE_OPT_EN;
+ val |= OPT1_RD_REPLY_BE_FIX_EN;
+ val |= OPT1_PCIE_BRIDGE_HOLE_DET_EN;
+ val |= OPT1_L1_INT_STATUS_MASK_POL;
+ __raw_writel(val, priv->base + PCIE_BRIDGE_OPT1_REG);
+
+ val = __raw_readl(priv->base + PCIE_BRIDGE_RC_INT_MASK_REG);
+ val |= PCIE_RC_INT_A;
+ val |= PCIE_RC_INT_B;
+ val |= PCIE_RC_INT_C;
+ val |= PCIE_RC_INT_D;
+ __raw_writel(val, priv->base + PCIE_BRIDGE_RC_INT_MASK_REG);
+
+ val = __raw_readl(priv->base + PCIE_BRIDGE_OPT2_REG);
+ /* enable credit checking and error checking */
+ val |= OPT2_TX_CREDIT_CHK_EN;
+ val |= OPT2_UBUS_UR_DECODE_DIS;
+ /* set device bus/func for the pcie device */
+ val |= (PCIE_BUS_DEVICE << OPT2_CFG_TYPE1_BUS_NO_SHIFT);
+ val |= OPT2_CFG_TYPE1_BD_SEL;
+ __raw_writel(val, priv->base + PCIE_BRIDGE_OPT2_REG);
+
+ /* setup class code as bridge */
+ val = __raw_readl(priv->base + PCIE_IDVAL3_REG);
+ val &= ~IDVAL3_CLASS_CODE_MASK;
+ val |= (PCI_CLASS_BRIDGE_PCI << IDVAL3_SUBCLASS_SHIFT);
+ __raw_writel(val, priv->base + PCIE_IDVAL3_REG);
+
+ /* disable bar1 size */
+ val = __raw_readl(priv->base + PCIE_CONFIG2_REG);
+ val &= ~CONFIG2_BAR1_SIZE_MASK;
+ __raw_writel(val, priv->base + PCIE_CONFIG2_REG);
+
+ /* set bar0 to little endian */
+ val = (bcm6328_pcie_mem_resource.start >> 20)
+ << BASEMASK_BASE_SHIFT;
+ val |= (bcm6328_pcie_mem_resource.end >> 20) << BASEMASK_MASK_SHIFT;
+ val |= BASEMASK_REMAP_EN;
+ __raw_writel(val, priv->base + PCIE_BRIDGE_BAR0_BASEMASK_REG);
+
+ val = (bcm6328_pcie_mem_resource.start >> 20)
+ << REBASE_ADDR_BASE_SHIFT;
+ __raw_writel(val, priv->base + PCIE_BRIDGE_BAR0_REBASE_ADDR_REG);
+}
+
+static int bcm6328_pcie_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct bcm6328_pcie *priv = &bcm6328_pcie;
+ int ret;
+
+ of_pci_check_probe_only();
+
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->base))
+ return PTR_ERR(priv->base);
+
+ priv->serdes = syscon_regmap_lookup_by_phandle(np, "brcm,serdes");
+ if (IS_ERR(priv->serdes))
+ return PTR_ERR(priv->serdes);
+
+ priv->reset = devm_reset_control_get_exclusive(dev, "pcie");
+ if (IS_ERR(priv->reset))
+ return PTR_ERR(priv->reset);
+
+ priv->reset_ext = devm_reset_control_get_exclusive(dev, "pcie-ext");
+ if (IS_ERR(priv->reset_ext))
+ return PTR_ERR(priv->reset_ext);
+
+ priv->reset_core = devm_reset_control_get_exclusive(dev, "pcie-core");
+ if (IS_ERR(priv->reset_core))
+ return PTR_ERR(priv->reset_core);
+
+ priv->reset_hard = devm_reset_control_get_optional_exclusive(dev,
+ "pcie-hard");
+ if (IS_ERR(priv->reset_hard))
+ return PTR_ERR(priv->reset_hard);
+
+ priv->clk = devm_clk_get(dev, "pcie");
+ if (IS_ERR(priv->clk))
+ return PTR_ERR(priv->clk);
+
+ ret = clk_prepare_enable(priv->clk);
+ if (ret) {
+ dev_err(dev, "could not enable clock: %d\n", ret);
+ return ret;
+ }
+
+ pci_load_of_ranges(&bcm6328_pcie_controller, np);
+ if (!bcm6328_pcie_mem_resource.start)
+ return -EINVAL;
+
+ of_pci_parse_bus_range(np, &bcm6328_pcie_busn_resource);
+
+ bcm6328_pcie_reset(priv);
+ bcm6328_pcie_setup(priv);
+
+ register_pci_controller(&bcm6328_pcie_controller);
+
+ return 0;
+}
+
+static const struct of_device_id bcm6328_pcie_of_match[] = {
+ { .compatible = "brcm,bcm6328-pcie", },
+ { .compatible = "brcm,bcm6362-pcie", },
+ { .compatible = "brcm,bcm63268-pcie", },
+ { /* sentinel */ },
+};
+
+static struct platform_driver bcm6328_pcie_driver = {
+ .driver = {
+ .name = "bcm6328-pcie",
+ .of_match_table = bcm6328_pcie_of_match,
+ },
+ .probe = bcm6328_pcie_probe,
+};
+builtin_platform_driver(bcm6328_pcie_driver);
--
2.27.0