blob: b934fdbc35c2814d098784c28246bf3364e90e01 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* PCIe host bridge driver for Apple system-on-chips.
*
* The HW is ECAM compliant.
*
* Initialization requires enabling power and clocks, along with a
* number of register pokes.
*
* Copyright (C) 2021 Alyssa Rosenzweig <alyssa@rosenzweig.io>
* Copyright (C) 2021 Google LLC
* Copyright (C) 2021 Corellium LLC
* Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
*
* Author: Alyssa Rosenzweig <alyssa@rosenzweig.io>
* Author: Marc Zyngier <maz@kernel.org>
*/
#include <common.h>
#include <dm.h>
#include <dm/device_compat.h>
#include <dm/devres.h>
#include <mapmem.h>
#include <pci.h>
#include <asm/io.h>
#include <asm-generic/gpio.h>
#include <linux/delay.h>
#include <linux/iopoll.h>
#define CORE_RC_PHYIF_CTL 0x00024
#define CORE_RC_PHYIF_CTL_RUN BIT(0)
#define CORE_RC_PHYIF_STAT 0x00028
#define CORE_RC_PHYIF_STAT_REFCLK BIT(4)
#define CORE_RC_CTL 0x00050
#define CORE_RC_CTL_RUN BIT(0)
#define CORE_RC_STAT 0x00058
#define CORE_RC_STAT_READY BIT(0)
#define CORE_FABRIC_STAT 0x04000
#define CORE_FABRIC_STAT_MASK 0x001F001F
#define CORE_LANE_CFG(port) (0x84000 + 0x4000 * (port))
#define CORE_LANE_CFG_REFCLK0REQ BIT(0)
#define CORE_LANE_CFG_REFCLK1REQ BIT(1)
#define CORE_LANE_CFG_REFCLK0ACK BIT(2)
#define CORE_LANE_CFG_REFCLK1ACK BIT(3)
#define CORE_LANE_CFG_REFCLKEN (BIT(9) | BIT(10))
#define CORE_LANE_CTL(port) (0x84004 + 0x4000 * (port))
#define CORE_LANE_CTL_CFGACC BIT(15)
#define PORT_LTSSMCTL 0x00080
#define PORT_LTSSMCTL_START BIT(0)
#define PORT_INTSTAT 0x00100
#define PORT_INT_TUNNEL_ERR 31
#define PORT_INT_CPL_TIMEOUT 23
#define PORT_INT_RID2SID_MAPERR 22
#define PORT_INT_CPL_ABORT 21
#define PORT_INT_MSI_BAD_DATA 19
#define PORT_INT_MSI_ERR 18
#define PORT_INT_REQADDR_GT32 17
#define PORT_INT_AF_TIMEOUT 15
#define PORT_INT_LINK_DOWN 14
#define PORT_INT_LINK_UP 12
#define PORT_INT_LINK_BWMGMT 11
#define PORT_INT_AER_MASK (15 << 4)
#define PORT_INT_PORT_ERR 4
#define PORT_INT_INTx(i) i
#define PORT_INT_INTx_MASK 15
#define PORT_INTMSK 0x00104
#define PORT_INTMSKSET 0x00108
#define PORT_INTMSKCLR 0x0010c
#define PORT_MSICFG 0x00124
#define PORT_MSICFG_EN BIT(0)
#define PORT_MSICFG_L2MSINUM_SHIFT 4
#define PORT_MSIBASE 0x00128
#define PORT_MSIBASE_1_SHIFT 16
#define PORT_MSIADDR 0x00168
#define PORT_LINKSTS 0x00208
#define PORT_LINKSTS_UP BIT(0)
#define PORT_LINKSTS_BUSY BIT(2)
#define PORT_LINKCMDSTS 0x00210
#define PORT_OUTS_NPREQS 0x00284
#define PORT_OUTS_NPREQS_REQ BIT(24)
#define PORT_OUTS_NPREQS_CPL BIT(16)
#define PORT_RXWR_FIFO 0x00288
#define PORT_RXWR_FIFO_HDR GENMASK(15, 10)
#define PORT_RXWR_FIFO_DATA GENMASK(9, 0)
#define PORT_RXRD_FIFO 0x0028C
#define PORT_RXRD_FIFO_REQ GENMASK(6, 0)
#define PORT_OUTS_CPLS 0x00290
#define PORT_OUTS_CPLS_SHRD GENMASK(14, 8)
#define PORT_OUTS_CPLS_WAIT GENMASK(6, 0)
#define PORT_APPCLK 0x00800
#define PORT_APPCLK_EN BIT(0)
#define PORT_APPCLK_CGDIS BIT(8)
#define PORT_STATUS 0x00804
#define PORT_STATUS_READY BIT(0)
#define PORT_REFCLK 0x00810
#define PORT_REFCLK_EN BIT(0)
#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_VALID BIT(31)
#define PORT_RID2SID_SID_SHIFT 16
#define PORT_RID2SID_BUS_SHIFT 8
#define PORT_RID2SID_DEV_SHIFT 3
#define PORT_RID2SID_FUNC_SHIFT 0
#define PORT_OUTS_PREQS_HDR 0x00980
#define PORT_OUTS_PREQS_HDR_MASK GENMASK(9, 0)
#define PORT_OUTS_PREQS_DATA 0x00984
#define PORT_OUTS_PREQS_DATA_MASK GENMASK(15, 0)
#define PORT_TUNCTRL 0x00988
#define PORT_TUNCTRL_PERST_ON BIT(0)
#define PORT_TUNCTRL_PERST_ACK_REQ BIT(1)
#define PORT_TUNSTAT 0x0098c
#define PORT_TUNSTAT_PERST_ON BIT(0)
#define PORT_TUNSTAT_PERST_ACK_PEND BIT(1)
#define PORT_PREFMEM_ENABLE 0x00994
struct apple_pcie_priv {
struct udevice *dev;
void __iomem *base;
void __iomem *cfg_base;
struct list_head ports;
};
struct apple_pcie_port {
struct apple_pcie_priv *pcie;
struct gpio_desc reset;
ofnode np;
void __iomem *base;
struct list_head entry;
int idx;
};
static void rmw_set(u32 set, void __iomem *addr)
{
writel_relaxed(readl_relaxed(addr) | set, addr);
}
static void rmw_clear(u32 clr, void __iomem *addr)
{
writel_relaxed(readl_relaxed(addr) & ~clr, addr);
}
static int apple_pcie_config_address(const struct udevice *bus,
pci_dev_t bdf, uint offset,
void **paddress)
{
struct apple_pcie_priv *pcie = dev_get_priv(bus);
void *addr;
addr = pcie->cfg_base;
addr += PCIE_ECAM_OFFSET(PCI_BUS(bdf), PCI_DEV(bdf),
PCI_FUNC(bdf), offset);
*paddress = addr;
return 0;
}
static int apple_pcie_read_config(const struct udevice *bus, pci_dev_t bdf,
uint offset, ulong *valuep,
enum pci_size_t size)
{
int ret;
ret = pci_generic_mmap_read_config(bus, apple_pcie_config_address,
bdf, offset, valuep, size);
return ret;
}
static int apple_pcie_write_config(struct udevice *bus, pci_dev_t bdf,
uint offset, ulong value,
enum pci_size_t size)
{
return pci_generic_mmap_write_config(bus, apple_pcie_config_address,
bdf, offset, value, size);
}
static const struct dm_pci_ops apple_pcie_ops = {
.read_config = apple_pcie_read_config,
.write_config = apple_pcie_write_config,
};
static int apple_pcie_setup_refclk(struct apple_pcie_priv *pcie,
struct apple_pcie_port *port)
{
u32 stat;
int res;
res = readl_poll_sleep_timeout(pcie->base + CORE_RC_PHYIF_STAT, stat,
stat & CORE_RC_PHYIF_STAT_REFCLK,
100, 50000);
if (res < 0)
return res;
rmw_set(CORE_LANE_CTL_CFGACC, pcie->base + CORE_LANE_CTL(port->idx));
rmw_set(CORE_LANE_CFG_REFCLK0REQ, pcie->base + CORE_LANE_CFG(port->idx));
res = readl_poll_sleep_timeout(pcie->base + CORE_LANE_CFG(port->idx),
stat, stat & CORE_LANE_CFG_REFCLK0ACK,
100, 50000);
if (res < 0)
return res;
rmw_set(CORE_LANE_CFG_REFCLK1REQ, pcie->base + CORE_LANE_CFG(port->idx));
res = readl_poll_sleep_timeout(pcie->base + CORE_LANE_CFG(port->idx),
stat, stat & CORE_LANE_CFG_REFCLK1ACK,
100, 50000);
if (res < 0)
return res;
rmw_clear(CORE_LANE_CTL_CFGACC, pcie->base + CORE_LANE_CTL(port->idx));
rmw_set(CORE_LANE_CFG_REFCLKEN, pcie->base + CORE_LANE_CFG(port->idx));
rmw_set(PORT_REFCLK_EN, port->base + PORT_REFCLK);
return 0;
}
static int apple_pcie_setup_port(struct apple_pcie_priv *pcie, ofnode np)
{
struct apple_pcie_port *port;
struct gpio_desc reset;
fdt_addr_t addr;
u32 stat, idx;
int ret;
ret = gpio_request_by_name_nodev(np, "reset-gpios", 0, &reset, 0);
if (ret)
return ret;
port = devm_kzalloc(pcie->dev, sizeof(*port), GFP_KERNEL);
if (!port)
return -ENOMEM;
ret = ofnode_read_u32_index(np, "reg", 0, &idx);
if (ret)
return ret;
/* Use the first reg entry to work out the port index */
port->idx = idx >> 11;
port->pcie = pcie;
port->reset = reset;
port->np = np;
addr = dev_read_addr_index(pcie->dev, port->idx + 2);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
port->base = map_sysmem(addr, 0);
rmw_set(PORT_APPCLK_EN, port->base + PORT_APPCLK);
/* Assert PERST# before setting up the clock */
dm_gpio_set_value(&reset, 1);
ret = apple_pcie_setup_refclk(pcie, port);
if (ret < 0)
return ret;
/* The minimal Tperst-clk value is 100us (PCIe CEM r5.0, 2.9.2) */
udelay(100);
/* Deassert PERST# */
rmw_set(PORT_PERST_OFF, port->base + PORT_PERST);
dm_gpio_set_value(&reset, 0);
/* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
udelay(100 * 1000);
ret = readl_poll_sleep_timeout(port->base + PORT_STATUS, stat,
stat & PORT_STATUS_READY, 100, 250000);
if (ret < 0) {
dev_err(pcie->dev, "port %d ready wait timeout\n", port->idx);
return ret;
}
rmw_clear(PORT_REFCLK_CGDIS, port->base + PORT_REFCLK);
rmw_clear(PORT_APPCLK_CGDIS, port->base + PORT_APPCLK);
list_add_tail(&port->entry, &pcie->ports);
writel_relaxed(PORT_LTSSMCTL_START, port->base + PORT_LTSSMCTL);
/*
* Deliberately ignore the link not coming up as connected
* devices (e.g. the WiFi controller) may not be powerd up.
*/
readl_poll_sleep_timeout(port->base + PORT_LINKSTS, stat,
(stat & PORT_LINKSTS_UP), 100, 100000);
return 0;
}
static int apple_pcie_probe(struct udevice *dev)
{
struct apple_pcie_priv *pcie = dev_get_priv(dev);
fdt_addr_t addr;
ofnode of_port;
int i, ret;
pcie->dev = dev;
addr = dev_read_addr_index(dev, 0);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
pcie->cfg_base = map_sysmem(addr, 0);
addr = dev_read_addr_index(dev, 1);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
pcie->base = map_sysmem(addr, 0);
INIT_LIST_HEAD(&pcie->ports);
for (of_port = ofnode_first_subnode(dev_ofnode(dev));
ofnode_valid(of_port);
of_port = ofnode_next_subnode(of_port)) {
if (!ofnode_is_enabled(of_port))
continue;
ret = apple_pcie_setup_port(pcie, of_port);
if (ret) {
dev_err(pcie->dev, "Port %d setup fail: %d\n", i, ret);
return ret;
}
}
return 0;
}
static int apple_pcie_remove(struct udevice *dev)
{
struct apple_pcie_priv *pcie = dev_get_priv(dev);
struct apple_pcie_port *port, *tmp;
list_for_each_entry_safe(port, tmp, &pcie->ports, entry) {
gpio_free_list_nodev(&port->reset, 1);
free(port);
}
return 0;
}
static const struct udevice_id apple_pcie_of_match[] = {
{ .compatible = "apple,pcie" },
{ /* sentinel */ }
};
U_BOOT_DRIVER(apple_pcie) = {
.name = "apple_pcie",
.id = UCLASS_PCI,
.of_match = apple_pcie_of_match,
.probe = apple_pcie_probe,
.remove = apple_pcie_remove,
.priv_auto = sizeof(struct apple_pcie_priv),
.ops = &apple_pcie_ops,
};