linux/drivers/pci/controller/pcie-brcmstb.c
Jim Quinlan 67211aadcb PCI: brcmstb: Add mechanism to turn on subdev regulators
Add a mechanism to identify standard PCIe regulators in the DT, allocate
them, and turn them on before the rest of the bus is scanned during
pci_host_probe().

The allocated structure that contains the regulators is stored in the port
driver dev.driver_data field.  Here is a point-by-point of how and when
this mechanism is activated:

If:
    -- PCIe RC driver sets pci_ops {add,remove)_bus to
       pci_subdev_regulators_{add,remove}_bus during its probe.
    -- There is a DT node "RB" under the host bridge DT node.
    -- During the RC driver's pci_host_probe() the add_bus callback
       is invoked where (bus->parent && pci_is_root_bus(bus->parent)
       is true

Then:
    -- A struct subdev_regulators structure will be allocated and
       assigned to bus->dev.driver_data.
    -- regulator_bulk_{get,enable} will be invoked on &bus->dev
       and the former will search for and process any
       vpcie{12v,3v3,3v3aux}-supply properties that reside in node "RB".
    -- The regulators will be turned off/on for any unbind/bind operations.
    -- The regulators will be turned off/on for any suspend/resumes, but
       only if the RC driver handles this on its own.  This will appear
       in a later commit for the pcie-brcmstb.c driver.

The unabridged reason for doing this is as follows.  We would like the
Broadcom STB PCIe root complex driver (and others) to be able to turn
off/on regulators[1] that provide power to endpoint[2] devices.  Typically,
the drivers of these endpoint devices are stock Linux drivers that are not
aware that these regulator(s) exist and must be turned on for the driver to
be probed.  The simple solution of course is to turn these regulators on at
boot and keep them on.  However, this solution does not satisfy at least
three of our usage modes:

  1. For example, one customer uses multiple PCIe controllers, but wants
     the ability to, by script invoking and unbind, turn any or all of them
     and their subdevices off to save power, e.g. when in battery mode.

  2. Another example is when a watchdog script discovers that an endpoint
     device is in an unresponsive state and would like to unbind, power
     toggle, and re-bind just the PCIe endpoint and controller.

  3. Of course we also want power turned off during suspend mode.  However,
     some endpoint devices may be able to "wake" during suspend and we need
     to recognise this case and veto the nominal act of turning off its
     regulator.  Such is the case with Wake-on-LAN and Wake-on-WLAN support
     where the PCIe endpoint device needs to be kept powered on in order to
     receive network packets and wake the system.

In all of these cases it is advantageous for the PCIe controller to govern
the turning off/on the regulators needed by the endpoint device.  The first
two cases can be done by simply unbinding and binding the PCIe controller,
if the controller has control of these regulators.

[1] These regulators typically govern the actual power supply to the
    endpoint chip.  Sometimes they may be the official PCIe socket
    power -- such as 3.3v or aux-3.3v.  Sometimes they are truly
    the regulator(s) that supply power to the EP chip.

[2] The 99% configuration of our boards is a single endpoint device
    attached to the PCIe controller.  I use the term endpoint but it could
    possibly mean a switch as well.

Link: https://lore.kernel.org/r/20220106160332.2143-6-jim2101024@gmail.com
Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2022-01-12 13:45:50 -06:00

1464 lines
42 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/* Copyright (C) 2009 - 2019 Broadcom */
#include <linux/bitfield.h>
#include <linux/bitops.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/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/msi.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/pci-ecam.h>
#include <linux/printk.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.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_CFG_PRIV1_LINK_CAPABILITY 0x04dc
#define PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK 0xc00
#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_SCB0_SIZE_MASK 0xf8000000
#define PCIE_MISC_MISC_CTRL_SCB1_SIZE_MASK 0x07c00000
#define PCIE_MISC_MISC_CTRL_SCB2_SIZE_MASK 0x0000001f
#define SCB_SIZE_MASK(x) PCIE_MISC_MISC_CTRL_SCB ## x ## _SIZE_MASK
#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) * 8)
#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) * 8)
#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_MSI_BAR_CONFIG_LO 0x4044
#define PCIE_MISC_MSI_BAR_CONFIG_HI 0x4048
#define PCIE_MISC_MSI_DATA_CONFIG 0x404c
#define PCIE_MISC_MSI_DATA_CONFIG_VAL_32 0xffe06540
#define PCIE_MISC_MSI_DATA_CONFIG_VAL_8 0xfff86540
#define PCIE_MISC_PCIE_CTRL 0x4064
#define PCIE_MISC_PCIE_CTRL_PCIE_L23_REQUEST_MASK 0x1
#define PCIE_MISC_PCIE_CTRL_PCIE_PERSTB_MASK 0x4
#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_REVISION 0x406c
#define BRCM_PCIE_HW_REV_33 0x0303
#define BRCM_PCIE_HW_REV_3_20 0x0320
#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_INTR2_CPU_BASE 0x4300
#define PCIE_MSI_INTR2_BASE 0x4500
/* Offsets from PCIE_INTR2_CPU_BASE and PCIE_MSI_INTR2_BASE */
#define MSI_INT_STATUS 0x0
#define MSI_INT_CLR 0x8
#define MSI_INT_MASK_SET 0x10
#define MSI_INT_MASK_CLR 0x14
#define PCIE_EXT_CFG_DATA 0x8000
#define PCIE_EXT_CFG_INDEX 0x9000
#define PCIE_RGR1_SW_INIT_1_PERST_MASK 0x1
#define PCIE_RGR1_SW_INIT_1_PERST_SHIFT 0x0
#define RGR1_SW_INIT_1_INIT_GENERIC_MASK 0x2
#define RGR1_SW_INIT_1_INIT_GENERIC_SHIFT 0x1
#define RGR1_SW_INIT_1_INIT_7278_MASK 0x1
#define RGR1_SW_INIT_1_INIT_7278_SHIFT 0x0
/* PCIe parameters */
#define BRCM_NUM_PCIE_OUT_WINS 0x4
#define BRCM_INT_PCI_MSI_NR 32
#define BRCM_INT_PCI_MSI_LEGACY_NR 8
#define BRCM_INT_PCI_MSI_SHIFT 0
#define BRCM_INT_PCI_MSI_MASK GENMASK(BRCM_INT_PCI_MSI_NR - 1, 0)
#define BRCM_INT_PCI_MSI_LEGACY_MASK GENMASK(31, \
32 - BRCM_INT_PCI_MSI_LEGACY_NR)
/* MSI target addresses */
#define BRCM_MSI_TARGET_ADDR_LT_4GB 0x0fffffffcULL
#define BRCM_MSI_TARGET_ADDR_GT_4GB 0xffffffffcULL
/* 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
#define PCIE_BRCM_MAX_MEMC 3
#define IDX_ADDR(pcie) (pcie->reg_offsets[EXT_CFG_INDEX])
#define DATA_ADDR(pcie) (pcie->reg_offsets[EXT_CFG_DATA])
#define PCIE_RGR1_SW_INIT_1(pcie) (pcie->reg_offsets[RGR1_SW_INIT_1])
/* Rescal registers */
#define PCIE_DVT_PMU_PCIE_PHY_CTRL 0xc700
#define PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_NFLDS 0x3
#define PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_DIG_RESET_MASK 0x4
#define PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_DIG_RESET_SHIFT 0x2
#define PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_RESET_MASK 0x2
#define PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_RESET_SHIFT 0x1
#define PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_PWRDN_MASK 0x1
#define PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_PWRDN_SHIFT 0x0
/* Forward declarations */
struct brcm_pcie;
static inline void brcm_pcie_bridge_sw_init_set_7278(struct brcm_pcie *pcie, u32 val);
static inline void brcm_pcie_bridge_sw_init_set_generic(struct brcm_pcie *pcie, u32 val);
static inline void brcm_pcie_perst_set_4908(struct brcm_pcie *pcie, u32 val);
static inline void brcm_pcie_perst_set_7278(struct brcm_pcie *pcie, u32 val);
static inline void brcm_pcie_perst_set_generic(struct brcm_pcie *pcie, u32 val);
enum {
RGR1_SW_INIT_1,
EXT_CFG_INDEX,
EXT_CFG_DATA,
};
enum {
RGR1_SW_INIT_1_INIT_MASK,
RGR1_SW_INIT_1_INIT_SHIFT,
};
enum pcie_type {
GENERIC,
BCM4908,
BCM7278,
BCM2711,
};
struct pcie_cfg_data {
const int *offsets;
const enum pcie_type type;
void (*perst_set)(struct brcm_pcie *pcie, u32 val);
void (*bridge_sw_init_set)(struct brcm_pcie *pcie, u32 val);
};
static const int pcie_offsets[] = {
[RGR1_SW_INIT_1] = 0x9210,
[EXT_CFG_INDEX] = 0x9000,
[EXT_CFG_DATA] = 0x9004,
};
static const struct pcie_cfg_data generic_cfg = {
.offsets = pcie_offsets,
.type = GENERIC,
.perst_set = brcm_pcie_perst_set_generic,
.bridge_sw_init_set = brcm_pcie_bridge_sw_init_set_generic,
};
static const struct pcie_cfg_data bcm4908_cfg = {
.offsets = pcie_offsets,
.type = BCM4908,
.perst_set = brcm_pcie_perst_set_4908,
.bridge_sw_init_set = brcm_pcie_bridge_sw_init_set_generic,
};
static const int pcie_offset_bcm7278[] = {
[RGR1_SW_INIT_1] = 0xc010,
[EXT_CFG_INDEX] = 0x9000,
[EXT_CFG_DATA] = 0x9004,
};
static const struct pcie_cfg_data bcm7278_cfg = {
.offsets = pcie_offset_bcm7278,
.type = BCM7278,
.perst_set = brcm_pcie_perst_set_7278,
.bridge_sw_init_set = brcm_pcie_bridge_sw_init_set_7278,
};
static const struct pcie_cfg_data bcm2711_cfg = {
.offsets = pcie_offsets,
.type = BCM2711,
.perst_set = brcm_pcie_perst_set_generic,
.bridge_sw_init_set = brcm_pcie_bridge_sw_init_set_generic,
};
struct subdev_regulators {
unsigned int num_supplies;
struct regulator_bulk_data supplies[];
};
static int pci_subdev_regulators_add_bus(struct pci_bus *bus);
static void pci_subdev_regulators_remove_bus(struct pci_bus *bus);
struct brcm_msi {
struct device *dev;
void __iomem *base;
struct device_node *np;
struct irq_domain *msi_domain;
struct irq_domain *inner_domain;
struct mutex lock; /* guards the alloc/free operations */
u64 target_addr;
int irq;
DECLARE_BITMAP(used, BRCM_INT_PCI_MSI_NR);
bool legacy;
/* Some chips have MSIs in bits [31..24] of a shared register. */
int legacy_shift;
int nr; /* No. of MSI available, depends on chip */
/* This is the base pointer for interrupt status/set/clr regs */
void __iomem *intr_base;
};
/* Internal PCIe Host Controller Information.*/
struct brcm_pcie {
struct device *dev;
void __iomem *base;
struct clk *clk;
struct device_node *np;
bool ssc;
int gen;
u64 msi_target_addr;
struct brcm_msi *msi;
const int *reg_offsets;
enum pcie_type type;
struct reset_control *rescal;
struct reset_control *perst_reset;
int num_memc;
u64 memc_size[PCIE_BRCM_MAX_MEMC];
u32 hw_rev;
void (*perst_set)(struct brcm_pcie *pcie, u32 val);
void (*bridge_sw_init_set)(struct brcm_pcie *pcie, u32 val);
};
/*
* 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;
}
static void *alloc_subdev_regulators(struct device *dev)
{
static const char * const supplies[] = {
"vpcie3v3",
"vpcie3v3aux",
"vpcie12v",
};
const size_t size = sizeof(struct subdev_regulators)
+ sizeof(struct regulator_bulk_data) * ARRAY_SIZE(supplies);
struct subdev_regulators *sr;
int i;
sr = devm_kzalloc(dev, size, GFP_KERNEL);
if (sr) {
sr->num_supplies = ARRAY_SIZE(supplies);
for (i = 0; i < ARRAY_SIZE(supplies); i++)
sr->supplies[i].supply = supplies[i];
}
return sr;
}
static int pci_subdev_regulators_add_bus(struct pci_bus *bus)
{
struct device *dev = &bus->dev;
struct subdev_regulators *sr;
int ret;
if (!dev->of_node || !bus->parent || !pci_is_root_bus(bus->parent))
return 0;
if (dev->driver_data)
dev_err(dev, "dev.driver_data unexpectedly non-NULL\n");
sr = alloc_subdev_regulators(dev);
if (!sr)
return -ENOMEM;
dev->driver_data = sr;
ret = regulator_bulk_get(dev, sr->num_supplies, sr->supplies);
if (ret)
return ret;
ret = regulator_bulk_enable(sr->num_supplies, sr->supplies);
if (ret) {
dev_err(dev, "failed to enable regulators for downstream device\n");
return ret;
}
return 0;
}
static void pci_subdev_regulators_remove_bus(struct pci_bus *bus)
{
struct device *dev = &bus->dev;
struct subdev_regulators *sr = dev->driver_data;
if (!sr || !bus->parent || !pci_is_root_bus(bus->parent))
return;
if (regulator_bulk_disable(sr->num_supplies, sr->supplies))
dev_err(dev, "failed to disable regulators for downstream device\n");
dev->driver_data = NULL;
}
/* 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));
}
static struct irq_chip brcm_msi_irq_chip = {
.name = "BRCM STB PCIe MSI",
.irq_ack = irq_chip_ack_parent,
.irq_mask = pci_msi_mask_irq,
.irq_unmask = pci_msi_unmask_irq,
};
static struct msi_domain_info brcm_msi_domain_info = {
/* Multi MSI is supported by the controller, but not by this driver */
.flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS),
.chip = &brcm_msi_irq_chip,
};
static void brcm_pcie_msi_isr(struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
unsigned long status;
struct brcm_msi *msi;
struct device *dev;
u32 bit;
chained_irq_enter(chip, desc);
msi = irq_desc_get_handler_data(desc);
dev = msi->dev;
status = readl(msi->intr_base + MSI_INT_STATUS);
status >>= msi->legacy_shift;
for_each_set_bit(bit, &status, msi->nr) {
int ret;
ret = generic_handle_domain_irq(msi->inner_domain, bit);
if (ret)
dev_dbg(dev, "unexpected MSI\n");
}
chained_irq_exit(chip, desc);
}
static void brcm_msi_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
{
struct brcm_msi *msi = irq_data_get_irq_chip_data(data);
msg->address_lo = lower_32_bits(msi->target_addr);
msg->address_hi = upper_32_bits(msi->target_addr);
msg->data = (0xffff & PCIE_MISC_MSI_DATA_CONFIG_VAL_32) | data->hwirq;
}
static int brcm_msi_set_affinity(struct irq_data *irq_data,
const struct cpumask *mask, bool force)
{
return -EINVAL;
}
static void brcm_msi_ack_irq(struct irq_data *data)
{
struct brcm_msi *msi = irq_data_get_irq_chip_data(data);
const int shift_amt = data->hwirq + msi->legacy_shift;
writel(1 << shift_amt, msi->intr_base + MSI_INT_CLR);
}
static struct irq_chip brcm_msi_bottom_irq_chip = {
.name = "BRCM STB MSI",
.irq_compose_msi_msg = brcm_msi_compose_msi_msg,
.irq_set_affinity = brcm_msi_set_affinity,
.irq_ack = brcm_msi_ack_irq,
};
static int brcm_msi_alloc(struct brcm_msi *msi)
{
int hwirq;
mutex_lock(&msi->lock);
hwirq = bitmap_find_free_region(msi->used, msi->nr, 0);
mutex_unlock(&msi->lock);
return hwirq;
}
static void brcm_msi_free(struct brcm_msi *msi, unsigned long hwirq)
{
mutex_lock(&msi->lock);
bitmap_release_region(msi->used, hwirq, 0);
mutex_unlock(&msi->lock);
}
static int brcm_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *args)
{
struct brcm_msi *msi = domain->host_data;
int hwirq;
hwirq = brcm_msi_alloc(msi);
if (hwirq < 0)
return hwirq;
irq_domain_set_info(domain, virq, (irq_hw_number_t)hwirq,
&brcm_msi_bottom_irq_chip, domain->host_data,
handle_edge_irq, NULL, NULL);
return 0;
}
static void brcm_irq_domain_free(struct irq_domain *domain,
unsigned int virq, unsigned int nr_irqs)
{
struct irq_data *d = irq_domain_get_irq_data(domain, virq);
struct brcm_msi *msi = irq_data_get_irq_chip_data(d);
brcm_msi_free(msi, d->hwirq);
}
static const struct irq_domain_ops msi_domain_ops = {
.alloc = brcm_irq_domain_alloc,
.free = brcm_irq_domain_free,
};
static int brcm_allocate_domains(struct brcm_msi *msi)
{
struct fwnode_handle *fwnode = of_node_to_fwnode(msi->np);
struct device *dev = msi->dev;
msi->inner_domain = irq_domain_add_linear(NULL, msi->nr, &msi_domain_ops, msi);
if (!msi->inner_domain) {
dev_err(dev, "failed to create IRQ domain\n");
return -ENOMEM;
}
msi->msi_domain = pci_msi_create_irq_domain(fwnode,
&brcm_msi_domain_info,
msi->inner_domain);
if (!msi->msi_domain) {
dev_err(dev, "failed to create MSI domain\n");
irq_domain_remove(msi->inner_domain);
return -ENOMEM;
}
return 0;
}
static void brcm_free_domains(struct brcm_msi *msi)
{
irq_domain_remove(msi->msi_domain);
irq_domain_remove(msi->inner_domain);
}
static void brcm_msi_remove(struct brcm_pcie *pcie)
{
struct brcm_msi *msi = pcie->msi;
if (!msi)
return;
irq_set_chained_handler_and_data(msi->irq, NULL, NULL);
brcm_free_domains(msi);
}
static void brcm_msi_set_regs(struct brcm_msi *msi)
{
u32 val = msi->legacy ? BRCM_INT_PCI_MSI_LEGACY_MASK :
BRCM_INT_PCI_MSI_MASK;
writel(val, msi->intr_base + MSI_INT_MASK_CLR);
writel(val, msi->intr_base + MSI_INT_CLR);
/*
* The 0 bit of PCIE_MISC_MSI_BAR_CONFIG_LO is repurposed to MSI
* enable, which we set to 1.
*/
writel(lower_32_bits(msi->target_addr) | 0x1,
msi->base + PCIE_MISC_MSI_BAR_CONFIG_LO);
writel(upper_32_bits(msi->target_addr),
msi->base + PCIE_MISC_MSI_BAR_CONFIG_HI);
val = msi->legacy ? PCIE_MISC_MSI_DATA_CONFIG_VAL_8 : PCIE_MISC_MSI_DATA_CONFIG_VAL_32;
writel(val, msi->base + PCIE_MISC_MSI_DATA_CONFIG);
}
static int brcm_pcie_enable_msi(struct brcm_pcie *pcie)
{
struct brcm_msi *msi;
int irq, ret;
struct device *dev = pcie->dev;
irq = irq_of_parse_and_map(dev->of_node, 1);
if (irq <= 0) {
dev_err(dev, "cannot map MSI interrupt\n");
return -ENODEV;
}
msi = devm_kzalloc(dev, sizeof(struct brcm_msi), GFP_KERNEL);
if (!msi)
return -ENOMEM;
mutex_init(&msi->lock);
msi->dev = dev;
msi->base = pcie->base;
msi->np = pcie->np;
msi->target_addr = pcie->msi_target_addr;
msi->irq = irq;
msi->legacy = pcie->hw_rev < BRCM_PCIE_HW_REV_33;
/*
* Sanity check to make sure that the 'used' bitmap in struct brcm_msi
* is large enough.
*/
BUILD_BUG_ON(BRCM_INT_PCI_MSI_LEGACY_NR > BRCM_INT_PCI_MSI_NR);
if (msi->legacy) {
msi->intr_base = msi->base + PCIE_INTR2_CPU_BASE;
msi->nr = BRCM_INT_PCI_MSI_LEGACY_NR;
msi->legacy_shift = 24;
} else {
msi->intr_base = msi->base + PCIE_MSI_INTR2_BASE;
msi->nr = BRCM_INT_PCI_MSI_NR;
msi->legacy_shift = 0;
}
ret = brcm_allocate_domains(msi);
if (ret)
return ret;
irq_set_chained_handler_and_data(msi->irq, brcm_pcie_msi_isr, msi);
brcm_msi_set_regs(msi);
pcie->msi = msi;
return 0;
}
/* 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;
}
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 = PCIE_ECAM_OFFSET(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,
.add_bus = pci_subdev_regulators_add_bus,
.remove_bus = pci_subdev_regulators_remove_bus,
};
static inline void brcm_pcie_bridge_sw_init_set_generic(struct brcm_pcie *pcie, u32 val)
{
u32 tmp, mask = RGR1_SW_INIT_1_INIT_GENERIC_MASK;
u32 shift = RGR1_SW_INIT_1_INIT_GENERIC_SHIFT;
tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
tmp = (tmp & ~mask) | ((val << shift) & mask);
writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
}
static inline void brcm_pcie_bridge_sw_init_set_7278(struct brcm_pcie *pcie, u32 val)
{
u32 tmp, mask = RGR1_SW_INIT_1_INIT_7278_MASK;
u32 shift = RGR1_SW_INIT_1_INIT_7278_SHIFT;
tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
tmp = (tmp & ~mask) | ((val << shift) & mask);
writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
}
static inline void brcm_pcie_perst_set_4908(struct brcm_pcie *pcie, u32 val)
{
if (WARN_ONCE(!pcie->perst_reset, "missing PERST# reset controller\n"))
return;
if (val)
reset_control_assert(pcie->perst_reset);
else
reset_control_deassert(pcie->perst_reset);
}
static inline void brcm_pcie_perst_set_7278(struct brcm_pcie *pcie, u32 val)
{
u32 tmp;
/* Perst bit has moved and assert value is 0 */
tmp = readl(pcie->base + PCIE_MISC_PCIE_CTRL);
u32p_replace_bits(&tmp, !val, PCIE_MISC_PCIE_CTRL_PCIE_PERSTB_MASK);
writel(tmp, pcie->base + PCIE_MISC_PCIE_CTRL);
}
static inline void brcm_pcie_perst_set_generic(struct brcm_pcie *pcie, u32 val)
{
u32 tmp;
tmp = readl(pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
u32p_replace_bits(&tmp, val, PCIE_RGR1_SW_INIT_1_PERST_MASK);
writel(tmp, pcie->base + PCIE_RGR1_SW_INIT_1(pcie));
}
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 resource_entry *entry;
struct device *dev = pcie->dev;
u64 lowest_pcie_addr = ~(u64)0;
int ret, i = 0;
u64 size = 0;
resource_list_for_each_entry(entry, &bridge->dma_ranges) {
u64 pcie_beg = entry->res->start - entry->offset;
size += entry->res->end - entry->res->start + 1;
if (pcie_beg < lowest_pcie_addr)
lowest_pcie_addr = pcie_beg;
}
if (lowest_pcie_addr == ~(u64)0) {
dev_err(dev, "DT node has no dma-ranges\n");
return -EINVAL;
}
ret = of_property_read_variable_u64_array(pcie->np, "brcm,scb-sizes", pcie->memc_size, 1,
PCIE_BRCM_MAX_MEMC);
if (ret <= 0) {
/* Make an educated guess */
pcie->num_memc = 1;
pcie->memc_size[0] = 1ULL << fls64(size - 1);
} else {
pcie->num_memc = ret;
}
/* Each memc is viewed through a "port" that is a power of 2 */
for (i = 0, size = 0; i < pcie->num_memc; i++)
size += pcie->memc_size[i];
/* System memory starts at this address in PCIe-space */
*rc_bar2_offset = lowest_pcie_addr;
/* The sum of all memc views must also be a power of 2 */
*rc_bar2_size = 1ULL << fls64(size - 1);
/*
* 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 - 1)) ||
(*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)
{
u64 rc_bar2_offset, rc_bar2_size;
void __iomem *base = pcie->base;
int ret, memc;
u32 tmp, burst, aspm_support;
/* Reset the bridge */
pcie->bridge_sw_init_set(pcie, 1);
usleep_range(100, 200);
/* Take the bridge out of reset */
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);
/*
* SCB_MAX_BURST_SIZE is a two bit field. For GENERIC chips it
* is encoded as 0=128, 1=256, 2=512, 3=Rsvd, for BCM7278 it
* is encoded as 0=Rsvd, 1=128, 2=256, 3=512.
*/
if (pcie->type == BCM2711)
burst = 0x0; /* 128B */
else if (pcie->type == BCM7278)
burst = 0x3; /* 512 bytes */
else
burst = 0x2; /* 512 bytes */
/* Set SCB_MAX_BURST_SIZE, CFG_READ_UR_MODE, SCB_ACCESS_EN */
tmp = readl(base + PCIE_MISC_MISC_CTRL);
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, burst, 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);
tmp = readl(base + PCIE_MISC_MISC_CTRL);
for (memc = 0; memc < pcie->num_memc; memc++) {
u32 scb_size_val = ilog2(pcie->memc_size[memc]) - 15;
if (memc == 0)
u32p_replace_bits(&tmp, scb_size_val, SCB_SIZE_MASK(0));
else if (memc == 1)
u32p_replace_bits(&tmp, scb_size_val, SCB_SIZE_MASK(1));
else if (memc == 2)
u32p_replace_bits(&tmp, scb_size_val, SCB_SIZE_MASK(2));
}
writel(tmp, base + PCIE_MISC_MISC_CTRL);
/*
* We ideally want the MSI target address to be located in the 32bit
* addressable memory area. Some devices might depend on it. This is
* possible either when the inbound window is located above the lower
* 4GB or when the inbound area is smaller than 4GB (taking into
* account the rounding-up we're forced to perform).
*/
if (rc_bar2_offset >= SZ_4G || (rc_bar2_size + rc_bar2_offset) < SZ_4G)
pcie->msi_target_addr = BRCM_MSI_TARGET_ADDR_LT_4GB;
else
pcie->msi_target_addr = BRCM_MSI_TARGET_ADDR_GT_4GB;
/* 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);
if (pcie->gen)
brcm_pcie_set_gen(pcie, pcie->gen);
/* Don't advertise L0s capability if 'aspm-no-l0s' */
aspm_support = PCIE_LINK_STATE_L1;
if (!of_property_read_bool(pcie->np, "aspm-no-l0s"))
aspm_support |= PCIE_LINK_STATE_L0S;
tmp = readl(base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
u32p_replace_bits(&tmp, aspm_support,
PCIE_RC_CFG_PRIV1_LINK_CAPABILITY_ASPM_SUPPORT_MASK);
writel(tmp, base + PCIE_RC_CFG_PRIV1_LINK_CAPABILITY);
/*
* 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);
return 0;
}
static int brcm_pcie_linkup(struct brcm_pcie *pcie)
{
struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
struct device *dev = pcie->dev;
void __iomem *base = pcie->base;
struct resource_entry *entry;
struct resource *res;
int num_out_wins = 0;
u16 nlw, cls, lnksta;
bool ssc_good = false;
u32 tmp;
int ret, i;
/* Unassert the fundamental reset */
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++;
}
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",
pci_speed_string(pcie_link_speed[cls]), 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 int brcm_phy_cntl(struct brcm_pcie *pcie, const int start)
{
static const u32 shifts[PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_NFLDS] = {
PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_PWRDN_SHIFT,
PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_RESET_SHIFT,
PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_DIG_RESET_SHIFT,};
static const u32 masks[PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_NFLDS] = {
PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_PWRDN_MASK,
PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_RESET_MASK,
PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_DIG_RESET_MASK,};
const int beg = start ? 0 : PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_NFLDS - 1;
const int end = start ? PCIE_DVT_PMU_PCIE_PHY_CTRL_DAST_NFLDS : -1;
u32 tmp, combined_mask = 0;
u32 val;
void __iomem *base = pcie->base;
int i, ret;
for (i = beg; i != end; start ? i++ : i--) {
val = start ? BIT_MASK(shifts[i]) : 0;
tmp = readl(base + PCIE_DVT_PMU_PCIE_PHY_CTRL);
tmp = (tmp & ~masks[i]) | (val & masks[i]);
writel(tmp, base + PCIE_DVT_PMU_PCIE_PHY_CTRL);
usleep_range(50, 200);
combined_mask |= masks[i];
}
tmp = readl(base + PCIE_DVT_PMU_PCIE_PHY_CTRL);
val = start ? combined_mask : 0;
ret = (tmp & combined_mask) == val ? 0 : -EIO;
if (ret)
dev_err(pcie->dev, "failed to %s phy\n", (start ? "start" : "stop"));
return ret;
}
static inline int brcm_phy_start(struct brcm_pcie *pcie)
{
return pcie->rescal ? brcm_phy_cntl(pcie, 1) : 0;
}
static inline int brcm_phy_stop(struct brcm_pcie *pcie)
{
return pcie->rescal ? brcm_phy_cntl(pcie, 0) : 0;
}
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 */
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 */
pcie->bridge_sw_init_set(pcie, 1);
}
static int brcm_pcie_suspend(struct device *dev)
{
struct brcm_pcie *pcie = dev_get_drvdata(dev);
int ret;
brcm_pcie_turn_off(pcie);
/*
* If brcm_phy_stop() returns an error, just dev_err(). If we
* return the error it will cause the suspend to fail and this is a
* forgivable offense that will probably be erased on resume.
*/
if (brcm_phy_stop(pcie))
dev_err(dev, "Could not stop phy for suspend\n");
ret = reset_control_rearm(pcie->rescal);
if (ret) {
dev_err(dev, "Could not rearm rescal reset\n");
return ret;
}
clk_disable_unprepare(pcie->clk);
return 0;
}
static int brcm_pcie_resume(struct device *dev)
{
struct brcm_pcie *pcie = dev_get_drvdata(dev);
void __iomem *base;
u32 tmp;
int ret;
base = pcie->base;
ret = clk_prepare_enable(pcie->clk);
if (ret)
return ret;
ret = reset_control_reset(pcie->rescal);
if (ret)
goto err_disable_clk;
ret = brcm_phy_start(pcie);
if (ret)
goto err_reset;
/* Take bridge out of reset so we can access the SERDES reg */
pcie->bridge_sw_init_set(pcie, 0);
/* SERDES_IDDQ = 0 */
tmp = readl(base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
u32p_replace_bits(&tmp, 0, PCIE_MISC_HARD_PCIE_HARD_DEBUG_SERDES_IDDQ_MASK);
writel(tmp, base + PCIE_MISC_HARD_PCIE_HARD_DEBUG);
/* wait for serdes to be stable */
udelay(100);
ret = brcm_pcie_setup(pcie);
if (ret)
goto err_reset;
ret = brcm_pcie_linkup(pcie);
if (ret)
goto err_reset;
if (pcie->msi)
brcm_msi_set_regs(pcie->msi);
return 0;
err_reset:
reset_control_rearm(pcie->rescal);
err_disable_clk:
clk_disable_unprepare(pcie->clk);
return ret;
}
static void __brcm_pcie_remove(struct brcm_pcie *pcie)
{
brcm_msi_remove(pcie);
brcm_pcie_turn_off(pcie);
if (brcm_phy_stop(pcie))
dev_err(pcie->dev, "Could not stop phy\n");
if (reset_control_rearm(pcie->rescal))
dev_err(pcie->dev, "Could not rearm rescal reset\n");
clk_disable_unprepare(pcie->clk);
}
static int brcm_pcie_remove(struct platform_device *pdev)
{
struct brcm_pcie *pcie = platform_get_drvdata(pdev);
struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
pci_stop_root_bus(bridge->bus);
pci_remove_root_bus(bridge->bus);
__brcm_pcie_remove(pcie);
return 0;
}
static const struct of_device_id brcm_pcie_match[] = {
{ .compatible = "brcm,bcm2711-pcie", .data = &bcm2711_cfg },
{ .compatible = "brcm,bcm4908-pcie", .data = &bcm4908_cfg },
{ .compatible = "brcm,bcm7211-pcie", .data = &generic_cfg },
{ .compatible = "brcm,bcm7278-pcie", .data = &bcm7278_cfg },
{ .compatible = "brcm,bcm7216-pcie", .data = &bcm7278_cfg },
{ .compatible = "brcm,bcm7445-pcie", .data = &generic_cfg },
{},
};
static int brcm_pcie_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node, *msi_np;
struct pci_host_bridge *bridge;
const struct pcie_cfg_data *data;
struct brcm_pcie *pcie;
int ret;
bridge = devm_pci_alloc_host_bridge(&pdev->dev, sizeof(*pcie));
if (!bridge)
return -ENOMEM;
data = of_device_get_match_data(&pdev->dev);
if (!data) {
pr_err("failed to look up compatible string\n");
return -EINVAL;
}
pcie = pci_host_bridge_priv(bridge);
pcie->dev = &pdev->dev;
pcie->np = np;
pcie->reg_offsets = data->offsets;
pcie->type = data->type;
pcie->perst_set = data->perst_set;
pcie->bridge_sw_init_set = data->bridge_sw_init_set;
pcie->base = devm_platform_ioremap_resource(pdev, 0);
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 = clk_prepare_enable(pcie->clk);
if (ret) {
dev_err(&pdev->dev, "could not enable clock\n");
return ret;
}
pcie->rescal = devm_reset_control_get_optional_shared(&pdev->dev, "rescal");
if (IS_ERR(pcie->rescal)) {
clk_disable_unprepare(pcie->clk);
return PTR_ERR(pcie->rescal);
}
pcie->perst_reset = devm_reset_control_get_optional_exclusive(&pdev->dev, "perst");
if (IS_ERR(pcie->perst_reset)) {
clk_disable_unprepare(pcie->clk);
return PTR_ERR(pcie->perst_reset);
}
ret = reset_control_reset(pcie->rescal);
if (ret)
dev_err(&pdev->dev, "failed to deassert 'rescal'\n");
ret = brcm_phy_start(pcie);
if (ret) {
reset_control_rearm(pcie->rescal);
clk_disable_unprepare(pcie->clk);
return ret;
}
ret = brcm_pcie_setup(pcie);
if (ret)
goto fail;
pcie->hw_rev = readl(pcie->base + PCIE_MISC_REVISION);
if (pcie->type == BCM4908 && pcie->hw_rev >= BRCM_PCIE_HW_REV_3_20) {
dev_err(pcie->dev, "hardware revision with unsupported PERST# setup\n");
ret = -ENODEV;
goto fail;
}
msi_np = of_parse_phandle(pcie->np, "msi-parent", 0);
if (pci_msi_enabled() && msi_np == pcie->np) {
ret = brcm_pcie_enable_msi(pcie);
if (ret) {
dev_err(pcie->dev, "probe of internal MSI failed");
goto fail;
}
}
bridge->ops = &brcm_pcie_ops;
bridge->sysdata = pcie;
platform_set_drvdata(pdev, pcie);
return pci_host_probe(bridge);
fail:
__brcm_pcie_remove(pcie);
return ret;
}
MODULE_DEVICE_TABLE(of, brcm_pcie_match);
static const struct dev_pm_ops brcm_pcie_pm_ops = {
.suspend = brcm_pcie_suspend,
.resume = brcm_pcie_resume,
};
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,
.pm = &brcm_pcie_pm_ops,
},
};
module_platform_driver(brcm_pcie_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Broadcom STB PCIe RC driver");
MODULE_AUTHOR("Broadcom");