From: Jim Quinlan <james.quinlan@broadcom.com>
Date: Mon, 16 Dec 2019 12:01:09 +0100
Subject: PCI: brcmstb: Add Broadcom STB PCIe host controller driver
Git-commit: c0452137034bda8f686dd9a2e167949bfffd6776
Patch-mainline: v5.6-rc1
References: jsc#SLE-7772
This adds a basic driver for Broadcom's STB PCIe controller, for now
aimed at Raspberry Pi 4's SoC, bcm2711.
Signed-off-by: Jim Quinlan <james.quinlan@broadcom.com>
Co-developed-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
[lorenzo.pieralisi@arm.com: updated brcm_pcie_get_rc_bar2_size_and_offset()according to https://lore.kernel.org/linux-pci/be8ddb33a7360af1815cf686f77f3f0913d02be3.camel@suse.de]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Andrew Murray <andrew.murray@arm.com>
Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
---
drivers/pci/controller/Kconfig | 8 +
drivers/pci/controller/Makefile | 1 +
drivers/pci/controller/pcie-brcmstb.c | 755 ++++++++++++++++++++++++++++++++++
3 files changed, 764 insertions(+)
diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index c77069c8ee5d..27504f108ee5 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -253,6 +253,14 @@ config VMD
To compile this driver as a module, choose M here: the
module will be called vmd.
+config PCIE_BRCMSTB
+ tristate "Broadcom Brcmstb PCIe host controller"
+ depends on ARCH_BCM2835 || COMPILE_TEST
+ depends on OF
+ help
+ Say Y here to enable PCIe host controller support for
+ Broadcom STB based SoCs, like the Raspberry Pi 4.
+
config PCI_HYPERV_INTERFACE
tristate "Hyper-V PCI Interface"
depends on X86 && HYPERV && PCI_MSI && PCI_MSI_IRQ_DOMAIN && X86_64
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index 3d4f597f15ce..01b2502a5323 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_PCIE_MEDIATEK) += pcie-mediatek.o
obj-$(CONFIG_PCIE_MOBIVEIL) += pcie-mobiveil.o
obj-$(CONFIG_PCIE_TANGO_SMP8759) += pcie-tango.o
obj-$(CONFIG_VMD) += vmd.o
+obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcmstb.o
# pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW
obj-y += dwc/
diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
new file mode 100644
index 000000000000..3250a2e6b1b4
--- /dev/null
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -0,0 +1,755 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Copyright (C) 2009 - 2019 Broadcom */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/compiler.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/log2.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/pci.h>
+#include <linux/printk.h>
+#include <linux/sizes.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include "../pci.h"
+
+/* BRCM_PCIE_CAP_REGS - Offset for the mandatory capability config regs */
+#define BRCM_PCIE_CAP_REGS 0x00ac
+
+/* Broadcom STB PCIe Register Offsets */
+#define PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1 0x0188
+#define PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1_ENDIAN_MODE_BAR2_MASK 0xc
+#define PCIE_RC_CFG_VENDOR_SPCIFIC_REG1_LITTLE_ENDIAN 0x0
+
+#define PCIE_RC_CFG_PRIV1_ID_VAL3 0x043c
+#define PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK 0xffffff
+
+#define PCIE_RC_DL_MDIO_ADDR 0x1100
+#define PCIE_RC_DL_MDIO_WR_DATA 0x1104
+#define PCIE_RC_DL_MDIO_RD_DATA 0x1108
+
+#define PCIE_MISC_MISC_CTRL 0x4008
+#define PCIE_MISC_MISC_CTRL_SCB_ACCESS_EN_MASK 0x1000
+#define PCIE_MISC_MISC_CTRL_CFG_READ_UR_MODE_MASK 0x2000
+#define PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_MASK 0x300000
+#define PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_128 0x0
+#define PCIE_MISC_MISC_CTRL_SCB0_SIZE_MASK 0xf8000000
+
+#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LO 0x400c
+#define PCIE_MEM_WIN0_LO(win) \
+ PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LO + ((win) * 4)
+
+#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_HI 0x4010
+#define PCIE_MEM_WIN0_HI(win) \
+ PCIE_MISC_CPU_2_PCIE_MEM_WIN0_HI + ((win) * 4)
+
+#define PCIE_MISC_RC_BAR1_CONFIG_LO 0x402c
+#define PCIE_MISC_RC_BAR1_CONFIG_LO_SIZE_MASK 0x1f
+
+#define PCIE_MISC_RC_BAR2_CONFIG_LO 0x4034
+#define PCIE_MISC_RC_BAR2_CONFIG_LO_SIZE_MASK 0x1f
+#define PCIE_MISC_RC_BAR2_CONFIG_HI 0x4038
+
+#define PCIE_MISC_RC_BAR3_CONFIG_LO 0x403c
+#define PCIE_MISC_RC_BAR3_CONFIG_LO_SIZE_MASK 0x1f
+
+#define PCIE_MISC_PCIE_CTRL 0x4064
+#define PCIE_MISC_PCIE_CTRL_PCIE_L23_REQUEST_MASK 0x1
+
+#define PCIE_MISC_PCIE_STATUS 0x4068
+#define PCIE_MISC_PCIE_STATUS_PCIE_PORT_MASK 0x80
+#define PCIE_MISC_PCIE_STATUS_PCIE_DL_ACTIVE_MASK 0x20
+#define PCIE_MISC_PCIE_STATUS_PCIE_PHYLINKUP_MASK 0x10
+#define PCIE_MISC_PCIE_STATUS_PCIE_LINK_IN_L23_MASK 0x40
+
+#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT 0x4070
+#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_LIMIT_MASK 0xfff00000
+#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_MASK 0xfff0
+#define PCIE_MEM_WIN0_BASE_LIMIT(win) \
+ PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT + ((win) * 4)
+
+#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI 0x4080
+#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI_BASE_MASK 0xff
+#define PCIE_MEM_WIN0_BASE_HI(win) \
+ PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI + ((win) * 8)
+
+#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI 0x4084
+#define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI_LIMIT_MASK 0xff
+#define PCIE_MEM_WIN0_LIMIT_HI(win) \
+ PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI + ((win) * 8)
+
+#define PCIE_MISC_HARD_PCIE_HARD_DEBUG 0x4204
+#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK 0x2
+#define PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK 0x08000000
+
+#define PCIE_MSI_INTR2_STATUS 0x4500
+#define PCIE_MSI_INTR2_CLR 0x4508
+#define PCIE_MSI_INTR2_MASK_SET 0x4510
+#define PCIE_MSI_INTR2_MASK_CLR 0x4514
+
+#define PCIE_EXT_CFG_DATA 0x8000
+
+#define PCIE_EXT_CFG_INDEX 0x9000
+#define PCIE_EXT_BUSNUM_SHIFT 20
+#define PCIE_EXT_SLOT_SHIFT 15
+#define PCIE_EXT_FUNC_SHIFT 12
+
+#define PCIE_RGR1_SW_INIT_1 0x9210
+#define PCIE_RGR1_SW_INIT_1_PERST_MASK 0x1
+#define PCIE_RGR1_SW_INIT_1_INIT_MASK 0x2
+
+/* PCIe parameters */
+#define BRCM_NUM_PCIE_OUT_WINS 0x4
+
+/* MDIO registers */
+#define MDIO_PORT0 0x0
+#define MDIO_DATA_MASK 0x7fffffff
+#define MDIO_PORT_MASK 0xf0000
+#define MDIO_REGAD_MASK 0xffff
+#define MDIO_CMD_MASK 0xfff00000
+#define MDIO_CMD_READ 0x1
+#define MDIO_CMD_WRITE 0x0
+#define MDIO_DATA_DONE_MASK 0x80000000
+#define MDIO_RD_DONE(x) (((x) & MDIO_DATA_DONE_MASK) ? 1 : 0)
+#define MDIO_WT_DONE(x) (((x) & MDIO_DATA_DONE_MASK) ? 0 : 1)
+#define SSC_REGS_ADDR 0x1100
+#define SET_ADDR_OFFSET 0x1f
+#define SSC_CNTL_OFFSET 0x2
+#define SSC_CNTL_OVRD_EN_MASK 0x8000
+#define SSC_CNTL_OVRD_VAL_MASK 0x4000
+#define SSC_STATUS_OFFSET 0x1
+#define SSC_STATUS_SSC_MASK 0x400
+#define SSC_STATUS_PLL_LOCK_MASK 0x800
+
+/* Internal PCIe Host Controller Information.*/
+struct brcm_pcie {
+ struct device *dev;
+ void __iomem *base;
+ struct clk *clk;
+ struct pci_bus *root_bus;
+ struct device_node *np;
+ bool ssc;
+ int gen;
+};
+
+/*
+ * This is to convert the size of the inbound "BAR" region to the
+ * non-linear values of PCIE_X_MISC_RC_BAR[123]_CONFIG_LO.SIZE
+ */
+static int brcm_pcie_encode_ibar_size(u64 size)
+{
+ int log2_in = ilog2(size);
+
+ if (log2_in >= 12 && log2_in <= 15)
+ /* Covers 4KB to 32KB (inclusive) */
+ return (log2_in - 12) + 0x1c;
+ else if (log2_in >= 16 && log2_in <= 35)
+ /* Covers 64KB to 32GB, (inclusive) */
+ return log2_in - 15;
+ /* Something is awry so disable */
+ return 0;
+}
+
+static u32 brcm_pcie_mdio_form_pkt(int port, int regad, int cmd)
+{
+ u32 pkt = 0;
+
+ pkt |= FIELD_PREP(MDIO_PORT_MASK, port);
+ pkt |= FIELD_PREP(MDIO_REGAD_MASK, regad);
+ pkt |= FIELD_PREP(MDIO_CMD_MASK, cmd);
+
+ return pkt;
+}
+
+/* negative return value indicates error */
+static int brcm_pcie_mdio_read(void __iomem *base, u8 port, u8 regad, u32 *val)
+{
+ int tries;
+ u32 data;
+
+ writel(brcm_pcie_mdio_form_pkt(port, regad, MDIO_CMD_READ),
+ base + PCIE_RC_DL_MDIO_ADDR);
+ readl(base + PCIE_RC_DL_MDIO_ADDR);
+
+ data = readl(base + PCIE_RC_DL_MDIO_RD_DATA);
+ for (tries = 0; !MDIO_RD_DONE(data) && tries < 10; tries++) {
+ udelay(10);
+ data = readl(base + PCIE_RC_DL_MDIO_RD_DATA);
+ }
+
+ *val = FIELD_GET(MDIO_DATA_MASK, data);
+ return MDIO_RD_DONE(data) ? 0 : -EIO;
+}
+
+/* negative return value indicates error */
+static int brcm_pcie_mdio_write(void __iomem *base, u8 port,
+ u8 regad, u16 wrdata)
+{
+ int tries;
+ u32 data;
+
+ writel(brcm_pcie_mdio_form_pkt(port, regad, MDIO_CMD_WRITE),
+ base + PCIE_RC_DL_MDIO_ADDR);
+ readl(base + PCIE_RC_DL_MDIO_ADDR);
+ writel(MDIO_DATA_DONE_MASK | wrdata, base + PCIE_RC_DL_MDIO_WR_DATA);
+
+ data = readl(base + PCIE_RC_DL_MDIO_WR_DATA);
+ for (tries = 0; !MDIO_WT_DONE(data) && tries < 10; tries++) {
+ udelay(10);
+ data = readl(base + PCIE_RC_DL_MDIO_WR_DATA);
+ }
+
+ return MDIO_WT_DONE(data) ? 0 : -EIO;
+}
+
+/*
+ * Configures device for Spread Spectrum Clocking (SSC) mode; a negative
+ * return value indicates error.
+ */
+static int brcm_pcie_set_ssc(struct brcm_pcie *pcie)
+{
+ int pll, ssc;
+ int ret;
+ u32 tmp;
+
+ ret = brcm_pcie_mdio_write(pcie->base, MDIO_PORT0, SET_ADDR_OFFSET,
+ SSC_REGS_ADDR);
+ if (ret < 0)
+ return ret;
+
+ ret = brcm_pcie_mdio_read(pcie->base, MDIO_PORT0,
+ SSC_CNTL_OFFSET, &tmp);
+ if (ret < 0)
+ return ret;
+
+ u32p_replace_bits(&tmp, 1, SSC_CNTL_OVRD_EN_MASK);
+ u32p_replace_bits(&tmp, 1, SSC_CNTL_OVRD_VAL_MASK);
+ ret = brcm_pcie_mdio_write(pcie->base, MDIO_PORT0,
+ SSC_CNTL_OFFSET, tmp);
+ if (ret < 0)
+ return ret;
+
+ usleep_range(1000, 2000);
+ ret = brcm_pcie_mdio_read(pcie->base, MDIO_PORT0,
+ SSC_STATUS_OFFSET, &tmp);
+ if (ret < 0)
+ return ret;
+
+ ssc = FIELD_GET(SSC_STATUS_SSC_MASK, tmp);
+ pll = FIELD_GET(SSC_STATUS_PLL_LOCK_MASK, tmp);
+
+ return ssc && pll ? 0 : -EIO;
+}
+
+/* Limits operation to a specific generation (1, 2, or 3) */
+static void brcm_pcie_set_gen(struct brcm_pcie *pcie, int gen)
+{
+ u16 lnkctl2 = readw(pcie->base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCTL2);
+ u32 lnkcap = readl(pcie->base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCAP);
+
+ lnkcap = (lnkcap & ~PCI_EXP_LNKCAP_SLS) | gen;
+ writel(lnkcap, pcie->base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCAP);
+
+ lnkctl2 = (lnkctl2 & ~0xf) | gen;
+ writew(lnkctl2, pcie->base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKCTL2);
+}
+
+static void brcm_pcie_set_outbound_win(struct brcm_pcie *pcie,
+ unsigned int win, u64 cpu_addr,
+ u64 pcie_addr, u64 size)
+{
+ u32 cpu_addr_mb_high, limit_addr_mb_high;
+ phys_addr_t cpu_addr_mb, limit_addr_mb;
+ int high_addr_shift;
+ u32 tmp;
+
+ /* Set the base of the pcie_addr window */
+ writel(lower_32_bits(pcie_addr), pcie->base + PCIE_MEM_WIN0_LO(win));
+ writel(upper_32_bits(pcie_addr), pcie->base + PCIE_MEM_WIN0_HI(win));
+
+ /* Write the addr base & limit lower bits (in MBs) */
+ cpu_addr_mb = cpu_addr / SZ_1M;
+ limit_addr_mb = (cpu_addr + size - 1) / SZ_1M;
+
+ tmp = readl(pcie->base + PCIE_MEM_WIN0_BASE_LIMIT(win));
+ u32p_replace_bits(&tmp, cpu_addr_mb,
+ PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_MASK);
+ u32p_replace_bits(&tmp, limit_addr_mb,
+ PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_LIMIT_MASK);
+ writel(tmp, pcie->base + PCIE_MEM_WIN0_BASE_LIMIT(win));
+
+ /* Write the cpu & limit addr upper bits */
+ high_addr_shift =
+ HWEIGHT32(PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_LIMIT_BASE_MASK);
+
+ cpu_addr_mb_high = cpu_addr_mb >> high_addr_shift;
+ tmp = readl(pcie->base + PCIE_MEM_WIN0_BASE_HI(win));
+ u32p_replace_bits(&tmp, cpu_addr_mb_high,
+ PCIE_MISC_CPU_2_PCIE_MEM_WIN0_BASE_HI_BASE_MASK);
+ writel(tmp, pcie->base + PCIE_MEM_WIN0_BASE_HI(win));
+
+ limit_addr_mb_high = limit_addr_mb >> high_addr_shift;
+ tmp = readl(pcie->base + PCIE_MEM_WIN0_LIMIT_HI(win));
+ u32p_replace_bits(&tmp, limit_addr_mb_high,
+ PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI_LIMIT_MASK);
+ writel(tmp, pcie->base + PCIE_MEM_WIN0_LIMIT_HI(win));
+}
+
+/* The controller is capable of serving in both RC and EP roles */
+static bool brcm_pcie_rc_mode(struct brcm_pcie *pcie)
+{
+ void __iomem *base = pcie->base;
+ u32 val = readl(base + PCIE_MISC_PCIE_STATUS);
+
+ return !!FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_PORT_MASK, val);
+}
+
+static bool brcm_pcie_link_up(struct brcm_pcie *pcie)
+{
+ u32 val = readl(pcie->base + PCIE_MISC_PCIE_STATUS);
+ u32 dla = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_DL_ACTIVE_MASK, val);
+ u32 plu = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_PHYLINKUP_MASK, val);
+
+ return dla && plu;
+}
+
+/* Configuration space read/write support */
+static inline int brcm_pcie_cfg_index(int busnr, int devfn, int reg)
+{
+ return ((PCI_SLOT(devfn) & 0x1f) << PCIE_EXT_SLOT_SHIFT)
+ | ((PCI_FUNC(devfn) & 0x07) << PCIE_EXT_FUNC_SHIFT)
+ | (busnr << PCIE_EXT_BUSNUM_SHIFT)
+ | (reg & ~3);
+}
+
+static void __iomem *brcm_pcie_map_conf(struct pci_bus *bus, unsigned int devfn,
+ int where)
+{
+ struct brcm_pcie *pcie = bus->sysdata;
+ void __iomem *base = pcie->base;
+ int idx;
+
+ /* Accesses to the RC go right to the RC registers if slot==0 */
+ if (pci_is_root_bus(bus))
+ return PCI_SLOT(devfn) ? NULL : base + where;
+
+ /* For devices, write to the config space index register */
+ idx = brcm_pcie_cfg_index(bus->number, devfn, 0);
+ writel(idx, pcie->base + PCIE_EXT_CFG_INDEX);
+ return base + PCIE_EXT_CFG_DATA + where;
+}
+
+static struct pci_ops brcm_pcie_ops = {
+ .map_bus = brcm_pcie_map_conf,
+ .read = pci_generic_config_read,
+ .write = pci_generic_config_write,
+};
+
+static inline void brcm_pcie_bridge_sw_init_set(struct brcm_pcie *pcie, u32 val)
+{
+ u32 tmp;
+
+ tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1);
+ u32p_replace_bits(&tmp, val, PCIE_RGR1_SW_INIT_1_INIT_MASK);
+ writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1);
+}
+
+static inline void brcm_pcie_perst_set(struct brcm_pcie *pcie, u32 val)
+{
+ u32 tmp;
+
+ tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1);
+ u32p_replace_bits(&tmp, val, PCIE_RGR1_SW_INIT_1_PERST_MASK);
+ writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1);
+}
+
+static inline int brcm_pcie_get_rc_bar2_size_and_offset(struct brcm_pcie *pcie,
+ u64 *rc_bar2_size,
+ u64 *rc_bar2_offset)
+{
+ struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
+ struct device *dev = pcie->dev;
+ struct resource_entry *entry;
+
+ entry = resource_list_first_type(&bridge->dma_ranges, IORESOURCE_MEM);
+ if (!entry)
+ return -ENODEV;
+
+
+ /*
+ * The controller expects the inbound window offset to be calculated as
+ * the difference between PCIe's address space and CPU's. The offset
+ * provided by the firmware is calculated the opposite way, so we
+ * negate it.
+ */
+ *rc_bar2_offset = -entry->offset;
+ *rc_bar2_size = 1ULL << fls64(entry->res->end - entry->res->start);
+
+ /*
+ * We validate the inbound memory view even though we should trust
+ * whatever the device-tree provides. This is because of an HW issue on
+ * early Raspberry Pi 4's revisions (bcm2711). It turns out its
+ * firmware has to dynamically edit dma-ranges due to a bug on the
+ * PCIe controller integration, which prohibits any access above the
+ * lower 3GB of memory. Given this, we decided to keep the dma-ranges
+ * in check, avoiding hard to debug device-tree related issues in the
+ * future:
+ *
+ * The PCIe host controller by design must set the inbound viewport to
+ * be a contiguous arrangement of all of the system's memory. In
+ * addition, its size mut be a power of two. To further complicate
+ * matters, the viewport must start on a pcie-address that is aligned
+ * on a multiple of its size. If a portion of the viewport does not
+ * represent system memory -- e.g. 3GB of memory requires a 4GB
+ * viewport -- we can map the outbound memory in or after 3GB and even
+ * though the viewport will overlap the outbound memory the controller
+ * will know to send outbound memory downstream and everything else
+ * upstream.
+ *
+ * For example:
+ *
+ * - The best-case scenario, memory up to 3GB, is to place the inbound
+ * region in the first 4GB of pcie-space, as some legacy devices can
+ * only address 32bits. We would also like to put the MSI under 4GB
+ * as well, since some devices require a 32bit MSI target address.
+ *
+ * - If the system memory is 4GB or larger we cannot start the inbound
+ * region at location 0 (since we have to allow some space for
+ * outbound memory @ 3GB). So instead it will start at the 1x
+ * multiple of its size
+ */
+ if (!*rc_bar2_size || *rc_bar2_offset % *rc_bar2_size ||
+ (*rc_bar2_offset < SZ_4G && *rc_bar2_offset > SZ_2G)) {
+ dev_err(dev, "Invalid rc_bar2_offset/size: size 0x%llx, off 0x%llx\n",
+ *rc_bar2_size, *rc_bar2_offset);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int brcm_pcie_setup(struct brcm_pcie *pcie)
+{
+ struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
+ u64 rc_bar2_offset, rc_bar2_size;
+ void __iomem *base = pcie->base;
+ struct device *dev = pcie->dev;
+ struct resource_entry *entry;
+ unsigned int scb_size_val;
+ bool ssc_good = false;
+ struct resource *res;
+ int num_out_wins = 0;
+ u16 nlw, cls, lnksta;
+ int i, ret;
+ u32 tmp;
+
+ /* Reset the bridge */
+ brcm_pcie_bridge_sw_init_set(pcie, 1);
+
+ usleep_range(100, 200);
+
+ /* Take the bridge out of reset */
+ brcm_pcie_bridge_sw_init_set(pcie, 0);
+
+ tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+ tmp &= ~PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK;
+ writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+ /* Wait for SerDes to be stable */
+ usleep_range(100, 200);
+
+ /* Set SCB_MAX_BURST_SIZE, CFG_READ_UR_MODE, SCB_ACCESS_EN */
+ u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_SCB_ACCESS_EN_MASK);
+ u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_CFG_READ_UR_MODE_MASK);
+ u32p_replace_bits(&tmp, PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_128,
+ PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_MASK);
+ writel(tmp, base + PCIE_MISC_MISC_CTRL);
+
+ ret = brcm_pcie_get_rc_bar2_size_and_offset(pcie, &rc_bar2_size,
+ &rc_bar2_offset);
+ if (ret)
+ return ret;
+
+ tmp = lower_32_bits(rc_bar2_offset);
+ u32p_replace_bits(&tmp, brcm_pcie_encode_ibar_size(rc_bar2_size),
+ PCIE_MISC_RC_BAR2_CONFIG_LO_SIZE_MASK);
+ writel(tmp, base + PCIE_MISC_RC_BAR2_CONFIG_LO);
+ writel(upper_32_bits(rc_bar2_offset),
+ base + PCIE_MISC_RC_BAR2_CONFIG_HI);
+
+ scb_size_val = rc_bar2_size ?
+ ilog2(rc_bar2_size) - 15 : 0xf; /* 0xf is 1GB */
+ tmp = readl(base + PCIE_MISC_MISC_CTRL);
+ u32p_replace_bits(&tmp, scb_size_val,
+ PCIE_MISC_MISC_CTRL_SCB0_SIZE_MASK);
+ writel(tmp, base + PCIE_MISC_MISC_CTRL);
+
+ /* disable the PCIe->GISB memory window (RC_BAR1) */
+ tmp = readl(base + PCIE_MISC_RC_BAR1_CONFIG_LO);
+ tmp &= ~PCIE_MISC_RC_BAR1_CONFIG_LO_SIZE_MASK;
+ writel(tmp, base + PCIE_MISC_RC_BAR1_CONFIG_LO);
+
+ /* disable the PCIe->SCB memory window (RC_BAR3) */
+ tmp = readl(base + PCIE_MISC_RC_BAR3_CONFIG_LO);
+ tmp &= ~PCIE_MISC_RC_BAR3_CONFIG_LO_SIZE_MASK;
+ writel(tmp, base + PCIE_MISC_RC_BAR3_CONFIG_LO);
+
+ /* Mask all interrupts since we are not handling any yet */
+ writel(0xffffffff, pcie->base + PCIE_MSI_INTR2_MASK_SET);
+
+ /* clear any interrupts we find on boot */
+ writel(0xffffffff, pcie->base + PCIE_MSI_INTR2_CLR);
+
+ if (pcie->gen)
+ brcm_pcie_set_gen(pcie, pcie->gen);
+
+ /* Unassert the fundamental reset */
+ brcm_pcie_perst_set(pcie, 0);
+
+ /*
+ * Give the RC/EP time to wake up, before trying to configure RC.
+ * Intermittently check status for link-up, up to a total of 100ms.
+ */
+ for (i = 0; i < 100 && !brcm_pcie_link_up(pcie); i += 5)
+ msleep(5);
+
+ if (!brcm_pcie_link_up(pcie)) {
+ dev_err(dev, "link down\n");
+ return -ENODEV;
+ }
+
+ if (!brcm_pcie_rc_mode(pcie)) {
+ dev_err(dev, "PCIe misconfigured; is in EP mode\n");
+ return -EINVAL;
+ }
+
+ resource_list_for_each_entry(entry, &bridge->windows) {
+ res = entry->res;
+
+ if (resource_type(res) != IORESOURCE_MEM)
+ continue;
+
+ if (num_out_wins >= BRCM_NUM_PCIE_OUT_WINS) {
+ dev_err(pcie->dev, "too many outbound wins\n");
+ return -EINVAL;
+ }
+
+ brcm_pcie_set_outbound_win(pcie, num_out_wins, res->start,
+ res->start - entry->offset,
+ resource_size(res));
+ num_out_wins++;
+ }
+
+ /*
+ * For config space accesses on the RC, show the right class for
+ * a PCIe-PCIe bridge (the default setting is to be EP mode).
+ */
+ tmp = readl(base + PCIE_RC_CFG_PRIV1_ID_VAL3);
+ u32p_replace_bits(&tmp, 0x060400,
+ PCIE_RC_CFG_PRIV1_ID_VAL3_CLASS_CODE_MASK);
+ writel(tmp, base + PCIE_RC_CFG_PRIV1_ID_VAL3);
+
+ if (pcie->ssc) {
+ ret = brcm_pcie_set_ssc(pcie);
+ if (ret == 0)
+ ssc_good = true;
+ else
+ dev_err(dev, "failed attempt to enter ssc mode\n");
+ }
+
+ lnksta = readw(base + BRCM_PCIE_CAP_REGS + PCI_EXP_LNKSTA);
+ cls = FIELD_GET(PCI_EXP_LNKSTA_CLS, lnksta);
+ nlw = FIELD_GET(PCI_EXP_LNKSTA_NLW, lnksta);
+ dev_info(dev, "link up, %s x%u %s\n",
+ PCIE_SPEED2STR(cls + PCI_SPEED_133MHz_PCIX_533),
+ nlw, ssc_good ? "(SSC)" : "(!SSC)");
+
+ /* PCIe->SCB endian mode for BAR */
+ tmp = readl(base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1);
+ u32p_replace_bits(&tmp, PCIE_RC_CFG_VENDOR_SPCIFIC_REG1_LITTLE_ENDIAN,
+ PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1_ENDIAN_MODE_BAR2_MASK);
+ writel(tmp, base + PCIE_RC_CFG_VENDOR_VENDOR_SPECIFIC_REG1);
+
+ /*
+ * Refclk from RC should be gated with CLKREQ# input when ASPM L0s,L1
+ * is enabled => setting the CLKREQ_DEBUG_ENABLE field to 1.
+ */
+ tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+ tmp |= PCIE_MISC_HARD_PCIE_HARD_DEBUG_CLKREQ_DEBUG_ENABLE_MASK;
+ writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+
+ return 0;
+}
+
+/* L23 is a low-power PCIe link state */
+static void brcm_pcie_enter_l23(struct brcm_pcie *pcie)
+{
+ void __iomem *base = pcie->base;
+ int l23, i;
+ u32 tmp;
+
+ /* Assert request for L23 */
+ tmp = readl(base + PCIE_MISC_PCIE_CTRL);
+ u32p_replace_bits(&tmp, 1, PCIE_MISC_PCIE_CTRL_PCIE_L23_REQUEST_MASK);
+ writel(tmp, base + PCIE_MISC_PCIE_CTRL);
+
+ /* Wait up to 36 msec for L23 */
+ tmp = readl(base + PCIE_MISC_PCIE_STATUS);
+ l23 = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_LINK_IN_L23_MASK, tmp);
+ for (i = 0; i < 15 && !l23; i++) {
+ usleep_range(2000, 2400);
+ tmp = readl(base + PCIE_MISC_PCIE_STATUS);
+ l23 = FIELD_GET(PCIE_MISC_PCIE_STATUS_PCIE_LINK_IN_L23_MASK,
+ tmp);
+ }
+
+ if (!l23)
+ dev_err(pcie->dev, "failed to enter low-power link state\n");
+}
+
+static void brcm_pcie_turn_off(struct brcm_pcie *pcie)
+{
+ void __iomem *base = pcie->base;
+ int tmp;
+
+ if (brcm_pcie_link_up(pcie))
+ brcm_pcie_enter_l23(pcie);
+ /* Assert fundamental reset */
+ brcm_pcie_perst_set(pcie, 1);
+
+ /* Deassert request for L23 in case it was asserted */
+ tmp = readl(base + PCIE_MISC_PCIE_CTRL);
+ u32p_replace_bits(&tmp, 0, PCIE_MISC_PCIE_CTRL_PCIE_L23_REQUEST_MASK);
+ writel(tmp, base + PCIE_MISC_PCIE_CTRL);
+
+ /* Turn off SerDes */
+ tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+ u32p_replace_bits(&tmp, 1, PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK);
+ writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
+
+ /* Shutdown PCIe bridge */
+ brcm_pcie_bridge_sw_init_set(pcie, 1);
+}
+
+static void __brcm_pcie_remove(struct brcm_pcie *pcie)
+{
+ brcm_pcie_turn_off(pcie);
+ clk_disable_unprepare(pcie->clk);
+ clk_put(pcie->clk);
+}
+
+static int brcm_pcie_remove(struct platform_device *pdev)
+{
+ struct brcm_pcie *pcie = platform_get_drvdata(pdev);
+
+ pci_stop_root_bus(pcie->root_bus);
+ pci_remove_root_bus(pcie->root_bus);
+ __brcm_pcie_remove(pcie);
+
+ return 0;
+}
+
+static int brcm_pcie_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct pci_host_bridge *bridge;
+ struct brcm_pcie *pcie;
+ struct pci_bus *child;
+ struct resource *res;
+ int ret;
+
+ bridge = devm_pci_alloc_host_bridge(&pdev->dev, sizeof(*pcie));
+ if (!bridge)
+ return -ENOMEM;
+
+ pcie = pci_host_bridge_priv(bridge);
+ pcie->dev = &pdev->dev;
+ pcie->np = np;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pcie->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(pcie->base))
+ return PTR_ERR(pcie->base);
+
+ pcie->clk = devm_clk_get_optional(&pdev->dev, "sw_pcie");
+ if (IS_ERR(pcie->clk))
+ return PTR_ERR(pcie->clk);
+
+ ret = of_pci_get_max_link_speed(np);
+ pcie->gen = (ret < 0) ? 0 : ret;
+
+ pcie->ssc = of_property_read_bool(np, "brcm,enable-ssc");
+
+ ret = pci_parse_request_of_pci_ranges(pcie->dev, &bridge->windows,
+ &bridge->dma_ranges, NULL);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(pcie->clk);
+ if (ret) {
+ dev_err(&pdev->dev, "could not enable clock\n");
+ return ret;
+ }
+
+ ret = brcm_pcie_setup(pcie);
+ if (ret)
+ goto fail;
+
+ bridge->dev.parent = &pdev->dev;
+ bridge->busnr = 0;
+ bridge->ops = &brcm_pcie_ops;
+ bridge->sysdata = pcie;
+ bridge->map_irq = of_irq_parse_and_map_pci;
+ bridge->swizzle_irq = pci_common_swizzle;
+
+ ret = pci_scan_root_bus_bridge(bridge);
+ if (ret < 0) {
+ dev_err(pcie->dev, "Scanning root bridge failed\n");
+ goto fail;
+ }
+
+ pci_assign_unassigned_bus_resources(bridge->bus);
+ list_for_each_entry(child, &bridge->bus->children, node)
+ pcie_bus_configure_settings(child);
+ pci_bus_add_devices(bridge->bus);
+ platform_set_drvdata(pdev, pcie);
+ pcie->root_bus = bridge->bus;
+
+ return 0;
+fail:
+ __brcm_pcie_remove(pcie);
+ return ret;
+}
+
+static const struct of_device_id brcm_pcie_match[] = {
+ { .compatible = "brcm,bcm2711-pcie" },
+ { .compatible = "brcm,bcm7445-pcie" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, brcm_pcie_match);
+
+static struct platform_driver brcm_pcie_driver = {
+ .probe = brcm_pcie_probe,
+ .remove = brcm_pcie_remove,
+ .driver = {
+ .name = "brcm-pcie",
+ .of_match_table = brcm_pcie_match,
+ },
+};
+module_platform_driver(brcm_pcie_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Broadcom STB PCIe RC driver");
+MODULE_AUTHOR("Broadcom");