kernel_samsung_a34x-permissive/drivers/pci/controller/pcie-cadence-host.c
2024-04-28 15:51:13 +02:00

375 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2017 Cadence
// Cadence PCIe host controller driver.
// Author: Cyrille Pitchen <cyrille.pitchen@free-electrons.com>
#include <linux/kernel.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include "pcie-cadence.h"
/**
* struct cdns_pcie_rc - private data for this PCIe Root Complex driver
* @pcie: Cadence PCIe controller
* @dev: pointer to PCIe device
* @cfg_res: start/end offsets in the physical system memory to map PCI
* configuration space accesses
* @bus_range: first/last buses behind the PCIe host controller
* @cfg_base: IO mapped window to access the PCI configuration space of a
* single function at a time
* @max_regions: maximum number of regions supported by the hardware
* @no_bar_nbits: Number of bits to keep for inbound (PCIe -> CPU) address
* translation (nbits sets into the "no BAR match" register)
* @vendor_id: PCI vendor ID
* @device_id: PCI device ID
*/
struct cdns_pcie_rc {
struct cdns_pcie pcie;
struct device *dev;
struct resource *cfg_res;
struct resource *bus_range;
void __iomem *cfg_base;
u32 max_regions;
u32 no_bar_nbits;
u16 vendor_id;
u16 device_id;
};
static void __iomem *cdns_pci_map_bus(struct pci_bus *bus, unsigned int devfn,
int where)
{
struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
struct cdns_pcie_rc *rc = pci_host_bridge_priv(bridge);
struct cdns_pcie *pcie = &rc->pcie;
unsigned int busn = bus->number;
u32 addr0, desc0;
if (busn == rc->bus_range->start) {
/*
* Only the root port (devfn == 0) is connected to this bus.
* All other PCI devices are behind some bridge hence on another
* bus.
*/
if (devfn)
return NULL;
return pcie->reg_base + (where & 0xfff);
}
/* Check that the link is up */
if (!(cdns_pcie_readl(pcie, CDNS_PCIE_LM_BASE) & 0x1))
return NULL;
/* Clear AXI link-down status */
cdns_pcie_writel(pcie, CDNS_PCIE_AT_LINKDOWN, 0x0);
/* Update Output registers for AXI region 0. */
addr0 = CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_NBITS(12) |
CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_DEVFN(devfn) |
CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_BUS(busn);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR0(0), addr0);
/* Configuration Type 0 or Type 1 access. */
desc0 = CDNS_PCIE_AT_OB_REGION_DESC0_HARDCODED_RID |
CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(0);
/*
* The bus number was already set once for all in desc1 by
* cdns_pcie_host_init_address_translation().
*/
if (busn == rc->bus_range->start + 1)
desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_CONF_TYPE0;
else
desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_CONF_TYPE1;
cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC0(0), desc0);
return rc->cfg_base + (where & 0xfff);
}
static struct pci_ops cdns_pcie_host_ops = {
.map_bus = cdns_pci_map_bus,
.read = pci_generic_config_read,
.write = pci_generic_config_write,
};
static const struct of_device_id cdns_pcie_host_of_match[] = {
{ .compatible = "cdns,cdns-pcie-host" },
{ },
};
static int cdns_pcie_host_init_root_port(struct cdns_pcie_rc *rc)
{
struct cdns_pcie *pcie = &rc->pcie;
u32 value, ctrl;
u32 id;
/*
* Set the root complex BAR configuration register:
* - disable both BAR0 and BAR1.
* - enable Prefetchable Memory Base and Limit registers in type 1
* config space (64 bits).
* - enable IO Base and Limit registers in type 1 config
* space (32 bits).
*/
ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_DISABLED;
value = CDNS_PCIE_LM_RC_BAR_CFG_BAR0_CTRL(ctrl) |
CDNS_PCIE_LM_RC_BAR_CFG_BAR1_CTRL(ctrl) |
CDNS_PCIE_LM_RC_BAR_CFG_PREFETCH_MEM_ENABLE |
CDNS_PCIE_LM_RC_BAR_CFG_PREFETCH_MEM_64BITS |
CDNS_PCIE_LM_RC_BAR_CFG_IO_ENABLE |
CDNS_PCIE_LM_RC_BAR_CFG_IO_32BITS;
cdns_pcie_writel(pcie, CDNS_PCIE_LM_RC_BAR_CFG, value);
/* Set root port configuration space */
if (rc->vendor_id != 0xffff) {
id = CDNS_PCIE_LM_ID_VENDOR(rc->vendor_id) |
CDNS_PCIE_LM_ID_SUBSYS(rc->vendor_id);
cdns_pcie_writel(pcie, CDNS_PCIE_LM_ID, id);
}
if (rc->device_id != 0xffff)
cdns_pcie_rp_writew(pcie, PCI_DEVICE_ID, rc->device_id);
cdns_pcie_rp_writeb(pcie, PCI_CLASS_REVISION, 0);
cdns_pcie_rp_writeb(pcie, PCI_CLASS_PROG, 0);
cdns_pcie_rp_writew(pcie, PCI_CLASS_DEVICE, PCI_CLASS_BRIDGE_PCI);
return 0;
}
static int cdns_pcie_host_init_address_translation(struct cdns_pcie_rc *rc)
{
struct cdns_pcie *pcie = &rc->pcie;
struct resource *cfg_res = rc->cfg_res;
struct resource *mem_res = pcie->mem_res;
struct resource *bus_range = rc->bus_range;
struct device *dev = rc->dev;
struct device_node *np = dev->of_node;
struct of_pci_range_parser parser;
struct of_pci_range range;
u32 addr0, addr1, desc1;
u64 cpu_addr;
int r, err;
/*
* Reserve region 0 for PCI configure space accesses:
* OB_REGION_PCI_ADDR0 and OB_REGION_DESC0 are updated dynamically by
* cdns_pci_map_bus(), other region registers are set here once for all.
*/
addr1 = 0; /* Should be programmed to zero. */
desc1 = CDNS_PCIE_AT_OB_REGION_DESC1_BUS(bus_range->start);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR1(0), addr1);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC1(0), desc1);
cpu_addr = cfg_res->start - mem_res->start;
addr0 = CDNS_PCIE_AT_OB_REGION_CPU_ADDR0_NBITS(12) |
(lower_32_bits(cpu_addr) & GENMASK(31, 8));
addr1 = upper_32_bits(cpu_addr);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(0), addr0);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(0), addr1);
err = of_pci_range_parser_init(&parser, np);
if (err)
return err;
r = 1;
for_each_of_pci_range(&parser, &range) {
bool is_io;
if (r >= rc->max_regions)
break;
if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_MEM)
is_io = false;
else if ((range.flags & IORESOURCE_TYPE_BITS) == IORESOURCE_IO)
is_io = true;
else
continue;
cdns_pcie_set_outbound_region(pcie, 0, r, is_io,
range.cpu_addr,
range.pci_addr,
range.size);
r++;
}
/*
* Set Root Port no BAR match Inbound Translation registers:
* needed for MSI and DMA.
* Root Port BAR0 and BAR1 are disabled, hence no need to set their
* inbound translation registers.
*/
addr0 = CDNS_PCIE_AT_IB_RP_BAR_ADDR0_NBITS(rc->no_bar_nbits);
addr1 = 0;
cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_RP_BAR_ADDR0(RP_NO_BAR), addr0);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_RP_BAR_ADDR1(RP_NO_BAR), addr1);
return 0;
}
static int cdns_pcie_host_init(struct device *dev,
struct list_head *resources,
struct cdns_pcie_rc *rc)
{
struct resource *bus_range = NULL;
int err;
/* Parse our PCI ranges and request their resources */
err = pci_parse_request_of_pci_ranges(dev, resources, &bus_range);
if (err)
return err;
rc->bus_range = bus_range;
rc->pcie.bus = bus_range->start;
err = cdns_pcie_host_init_root_port(rc);
if (err)
goto err_out;
err = cdns_pcie_host_init_address_translation(rc);
if (err)
goto err_out;
return 0;
err_out:
pci_free_resource_list(resources);
return err;
}
static int cdns_pcie_host_probe(struct platform_device *pdev)
{
const char *type;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct pci_host_bridge *bridge;
struct list_head resources;
struct cdns_pcie_rc *rc;
struct cdns_pcie *pcie;
struct resource *res;
int ret;
int phy_count;
bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
if (!bridge)
return -ENOMEM;
rc = pci_host_bridge_priv(bridge);
rc->dev = dev;
pcie = &rc->pcie;
pcie->is_rc = true;
rc->max_regions = 32;
of_property_read_u32(np, "cdns,max-outbound-regions", &rc->max_regions);
rc->no_bar_nbits = 32;
of_property_read_u32(np, "cdns,no-bar-match-nbits", &rc->no_bar_nbits);
rc->vendor_id = 0xffff;
of_property_read_u16(np, "vendor-id", &rc->vendor_id);
rc->device_id = 0xffff;
of_property_read_u16(np, "device-id", &rc->device_id);
type = of_get_property(np, "device_type", NULL);
if (!type || strcmp(type, "pci")) {
dev_err(dev, "invalid \"device_type\" %s\n", type);
return -EINVAL;
}
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "reg");
pcie->reg_base = devm_ioremap_resource(dev, res);
if (IS_ERR(pcie->reg_base)) {
dev_err(dev, "missing \"reg\"\n");
return PTR_ERR(pcie->reg_base);
}
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
rc->cfg_base = devm_pci_remap_cfg_resource(dev, res);
if (IS_ERR(rc->cfg_base)) {
dev_err(dev, "missing \"cfg\"\n");
return PTR_ERR(rc->cfg_base);
}
rc->cfg_res = res;
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem");
if (!res) {
dev_err(dev, "missing \"mem\"\n");
return -EINVAL;
}
pcie->mem_res = res;
ret = cdns_pcie_init_phy(dev, pcie);
if (ret) {
dev_err(dev, "failed to init phy\n");
return ret;
}
platform_set_drvdata(pdev, pcie);
pm_runtime_enable(dev);
ret = pm_runtime_get_sync(dev);
if (ret < 0) {
dev_err(dev, "pm_runtime_get_sync() failed\n");
goto err_get_sync;
}
ret = cdns_pcie_host_init(dev, &resources, rc);
if (ret)
goto err_init;
list_splice_init(&resources, &bridge->windows);
bridge->dev.parent = dev;
bridge->busnr = pcie->bus;
bridge->ops = &cdns_pcie_host_ops;
bridge->map_irq = of_irq_parse_and_map_pci;
bridge->swizzle_irq = pci_common_swizzle;
ret = pci_host_probe(bridge);
if (ret < 0)
goto err_host_probe;
return 0;
err_host_probe:
pci_free_resource_list(&resources);
err_init:
pm_runtime_put_sync(dev);
err_get_sync:
pm_runtime_disable(dev);
cdns_pcie_disable_phy(pcie);
phy_count = pcie->phy_count;
while (phy_count--)
device_link_del(pcie->link[phy_count]);
return ret;
}
static void cdns_pcie_shutdown(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct cdns_pcie *pcie = dev_get_drvdata(dev);
int ret;
ret = pm_runtime_put_sync(dev);
if (ret < 0)
dev_dbg(dev, "pm_runtime_put_sync failed\n");
pm_runtime_disable(dev);
cdns_pcie_disable_phy(pcie);
}
static struct platform_driver cdns_pcie_host_driver = {
.driver = {
.name = "cdns-pcie-host",
.of_match_table = cdns_pcie_host_of_match,
.pm = &cdns_pcie_pm_ops,
},
.probe = cdns_pcie_host_probe,
.shutdown = cdns_pcie_shutdown,
};
builtin_platform_driver(cdns_pcie_host_driver);