Commit 37dddf14 authored by Cyrille Pitchen's avatar Cyrille Pitchen Committed by Lorenzo Pieralisi
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PCI: cadence: Add EndPoint Controller driver for Cadence PCIe controller



This patch adds support to the Cadence PCIe controller in endpoint mode.

Since pieces of source code are shared with the host driver (Root
Complex mode), we create a new directory under drivers/pci dedicated to
the Cadence PCIe controller. The common code is placed into
drivers/pci/cadence/pcie-cadence.c and used by both the host and
endpoint controller drivers.
Signed-off-by: default avatarCyrille Pitchen <cyrille.pitchen@free-electrons.com>
Signed-off-by: Lorenzo Pieralisi's avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
parent 6618f4d3
......@@ -10407,7 +10407,7 @@ M: Alan Douglas <adouglas@cadence.com>
L: linux-pci@vger.kernel.org
S: Maintained
F: Documentation/devicetree/bindings/pci/cdns,*.txt
F: drivers/pci/host/pcie-cadence*
F: drivers/pci/cadence/pcie-cadence*
PCI DRIVER FOR FREESCALE LAYERSCAPE
M: Minghuan Lian <minghuan.Lian@freescale.com>
......
......@@ -136,6 +136,7 @@ config PCI_HYPERV
PCI devices from a PCI backend to support PCI driver domains.
source "drivers/pci/hotplug/Kconfig"
source "drivers/pci/cadence/Kconfig"
source "drivers/pci/dwc/Kconfig"
source "drivers/pci/host/Kconfig"
source "drivers/pci/endpoint/Kconfig"
......
......@@ -56,5 +56,6 @@ obj-y += switch/
obj-$(CONFIG_PCI_ENDPOINT) += endpoint/
# Endpoint library must be initialized before its users
obj-$(CONFIG_PCIE_CADENCE) += cadence/
# pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW
obj-y += dwc/
menu "Cadence PCIe controllers support"
config PCIE_CADENCE
bool
config PCIE_CADENCE_HOST
bool "Cadence PCIe host controller"
depends on OF
depends on PCI
select IRQ_DOMAIN
select PCIE_CADENCE
help
Say Y here if you want to support the Cadence PCIe controller in host
mode. This PCIe controller may be embedded into many different vendors
SoCs.
config PCIE_CADENCE_EP
bool "Cadence PCIe endpoint controller"
depends on OF
depends on PCI_ENDPOINT
select PCIE_CADENCE
help
Say Y here if you want to support the Cadence PCIe controller in
endpoint mode. This PCIe controller may be embedded into many
different vendors SoCs.
endmenu
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_PCIE_CADENCE) += pcie-cadence.o
obj-$(CONFIG_PCIE_CADENCE_HOST) += pcie-cadence-host.o
obj-$(CONFIG_PCIE_CADENCE_EP) += pcie-cadence-ep.o
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2017 Cadence
// Cadence PCIe endpoint controller driver.
// Author: Cyrille Pitchen <cyrille.pitchen@free-electrons.com>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/pci-epc.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/sizes.h>
#include "pcie-cadence.h"
#define CDNS_PCIE_EP_MIN_APERTURE 128 /* 128 bytes */
#define CDNS_PCIE_EP_IRQ_PCI_ADDR_NONE 0x1
#define CDNS_PCIE_EP_IRQ_PCI_ADDR_LEGACY 0x3
/**
* struct cdns_pcie_ep - private data for this PCIe endpoint controller driver
* @pcie: Cadence PCIe controller
* @max_regions: maximum number of regions supported by hardware
* @ob_region_map: bitmask of mapped outbound regions
* @ob_addr: base addresses in the AXI bus where the outbound regions start
* @irq_phys_addr: base address on the AXI bus where the MSI/legacy IRQ
* dedicated outbound regions is mapped.
* @irq_cpu_addr: base address in the CPU space where a write access triggers
* the sending of a memory write (MSI) / normal message (legacy
* IRQ) TLP through the PCIe bus.
* @irq_pci_addr: used to save the current mapping of the MSI/legacy IRQ
* dedicated outbound region.
* @irq_pci_fn: the latest PCI function that has updated the mapping of
* the MSI/legacy IRQ dedicated outbound region.
* @irq_pending: bitmask of asserted legacy IRQs.
*/
struct cdns_pcie_ep {
struct cdns_pcie pcie;
u32 max_regions;
unsigned long ob_region_map;
phys_addr_t *ob_addr;
phys_addr_t irq_phys_addr;
void __iomem *irq_cpu_addr;
u64 irq_pci_addr;
u8 irq_pci_fn;
u8 irq_pending;
};
static int cdns_pcie_ep_write_header(struct pci_epc *epc, u8 fn,
struct pci_epf_header *hdr)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
cdns_pcie_ep_fn_writew(pcie, fn, PCI_DEVICE_ID, hdr->deviceid);
cdns_pcie_ep_fn_writeb(pcie, fn, PCI_REVISION_ID, hdr->revid);
cdns_pcie_ep_fn_writeb(pcie, fn, PCI_CLASS_PROG, hdr->progif_code);
cdns_pcie_ep_fn_writew(pcie, fn, PCI_CLASS_DEVICE,
hdr->subclass_code | hdr->baseclass_code << 8);
cdns_pcie_ep_fn_writeb(pcie, fn, PCI_CACHE_LINE_SIZE,
hdr->cache_line_size);
cdns_pcie_ep_fn_writew(pcie, fn, PCI_SUBSYSTEM_ID, hdr->subsys_id);
cdns_pcie_ep_fn_writeb(pcie, fn, PCI_INTERRUPT_PIN, hdr->interrupt_pin);
/*
* Vendor ID can only be modified from function 0, all other functions
* use the same vendor ID as function 0.
*/
if (fn == 0) {
/* Update the vendor IDs. */
u32 id = CDNS_PCIE_LM_ID_VENDOR(hdr->vendorid) |
CDNS_PCIE_LM_ID_SUBSYS(hdr->subsys_vendor_id);
cdns_pcie_writel(pcie, CDNS_PCIE_LM_ID, id);
}
return 0;
}
static int cdns_pcie_ep_set_bar(struct pci_epc *epc, u8 fn, enum pci_barno bar,
dma_addr_t bar_phys, size_t size, int flags)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
u32 addr0, addr1, reg, cfg, b, aperture, ctrl;
u64 sz;
/* BAR size is 2^(aperture + 7) */
sz = max_t(size_t, size, CDNS_PCIE_EP_MIN_APERTURE);
/*
* roundup_pow_of_two() returns an unsigned long, which is not suited
* for 64bit values.
*/
sz = 1ULL << fls64(sz - 1);
aperture = ilog2(sz) - 7; /* 128B -> 0, 256B -> 1, 512B -> 2, ... */
if ((flags & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_IO_32BITS;
} else {
bool is_prefetch = !!(flags & PCI_BASE_ADDRESS_MEM_PREFETCH);
bool is_64bits = sz > SZ_2G;
if (is_64bits && (bar & 1))
return -EINVAL;
if (is_64bits && is_prefetch)
ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_PREFETCH_MEM_64BITS;
else if (is_prefetch)
ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_PREFETCH_MEM_32BITS;
else if (is_64bits)
ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_MEM_64BITS;
else
ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_MEM_32BITS;
}
addr0 = lower_32_bits(bar_phys);
addr1 = upper_32_bits(bar_phys);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR0(fn, bar),
addr0);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR1(fn, bar),
addr1);
if (bar < BAR_4) {
reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn);
b = bar;
} else {
reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn);
b = bar - BAR_4;
}
cfg = cdns_pcie_readl(pcie, reg);
cfg &= ~(CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) |
CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL_MASK(b));
cfg |= (CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE(b, aperture) |
CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL(b, ctrl));
cdns_pcie_writel(pcie, reg, cfg);
return 0;
}
static void cdns_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn,
enum pci_barno bar)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
u32 reg, cfg, b, ctrl;
if (bar < BAR_4) {
reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG0(fn);
b = bar;
} else {
reg = CDNS_PCIE_LM_EP_FUNC_BAR_CFG1(fn);
b = bar - BAR_4;
}
ctrl = CDNS_PCIE_LM_BAR_CFG_CTRL_DISABLED;
cfg = cdns_pcie_readl(pcie, reg);
cfg &= ~(CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) |
CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL_MASK(b));
cfg |= CDNS_PCIE_LM_EP_FUNC_BAR_CFG_BAR_CTRL(b, ctrl);
cdns_pcie_writel(pcie, reg, cfg);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR0(fn, bar), 0);
cdns_pcie_writel(pcie, CDNS_PCIE_AT_IB_EP_FUNC_BAR_ADDR1(fn, bar), 0);
}
static int cdns_pcie_ep_map_addr(struct pci_epc *epc, u8 fn, phys_addr_t addr,
u64 pci_addr, size_t size)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
u32 r;
r = find_first_zero_bit(&ep->ob_region_map,
sizeof(ep->ob_region_map) * BITS_PER_LONG);
if (r >= ep->max_regions - 1) {
dev_err(&epc->dev, "no free outbound region\n");
return -EINVAL;
}
cdns_pcie_set_outbound_region(pcie, fn, r, false, addr, pci_addr, size);
set_bit(r, &ep->ob_region_map);
ep->ob_addr[r] = addr;
return 0;
}
static void cdns_pcie_ep_unmap_addr(struct pci_epc *epc, u8 fn,
phys_addr_t addr)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
u32 r;
for (r = 0; r < ep->max_regions - 1; r++)
if (ep->ob_addr[r] == addr)
break;
if (r == ep->max_regions - 1)
return;
cdns_pcie_reset_outbound_region(pcie, r);
ep->ob_addr[r] = 0;
clear_bit(r, &ep->ob_region_map);
}
static int cdns_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 mmc)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
u16 flags;
/*
* Set the Multiple Message Capable bitfield into the Message Control
* register.
*/
flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_FLAGS);
flags = (flags & ~PCI_MSI_FLAGS_QMASK) | (mmc << 1);
flags |= PCI_MSI_FLAGS_64BIT;
flags &= ~PCI_MSI_FLAGS_MASKBIT;
cdns_pcie_ep_fn_writew(pcie, fn, cap + PCI_MSI_FLAGS, flags);
return 0;
}
static int cdns_pcie_ep_get_msi(struct pci_epc *epc, u8 fn)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
u16 flags, mmc, mme;
/* Validate that the MSI feature is actually enabled. */
flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_FLAGS);
if (!(flags & PCI_MSI_FLAGS_ENABLE))
return -EINVAL;
/*
* Get the Multiple Message Enable bitfield from the Message Control
* register.
*/
mmc = (flags & PCI_MSI_FLAGS_QMASK) >> 1;
mme = (flags & PCI_MSI_FLAGS_QSIZE) >> 4;
return mme;
}
static void cdns_pcie_ep_assert_intx(struct cdns_pcie_ep *ep, u8 fn,
u8 intx, bool is_asserted)
{
struct cdns_pcie *pcie = &ep->pcie;
u32 r = ep->max_regions - 1;
u32 offset;
u16 status;
u8 msg_code;
intx &= 3;
/* Set the outbound region if needed. */
if (unlikely(ep->irq_pci_addr != CDNS_PCIE_EP_IRQ_PCI_ADDR_LEGACY ||
ep->irq_pci_fn != fn)) {
/* Last region was reserved for IRQ writes. */
cdns_pcie_set_outbound_region_for_normal_msg(pcie, fn, r,
ep->irq_phys_addr);
ep->irq_pci_addr = CDNS_PCIE_EP_IRQ_PCI_ADDR_LEGACY;
ep->irq_pci_fn = fn;
}
if (is_asserted) {
ep->irq_pending |= BIT(intx);
msg_code = MSG_CODE_ASSERT_INTA + intx;
} else {
ep->irq_pending &= ~BIT(intx);
msg_code = MSG_CODE_DEASSERT_INTA + intx;
}
status = cdns_pcie_ep_fn_readw(pcie, fn, PCI_STATUS);
if (((status & PCI_STATUS_INTERRUPT) != 0) ^ (ep->irq_pending != 0)) {
status ^= PCI_STATUS_INTERRUPT;
cdns_pcie_ep_fn_writew(pcie, fn, PCI_STATUS, status);
}
offset = CDNS_PCIE_NORMAL_MSG_ROUTING(MSG_ROUTING_LOCAL) |
CDNS_PCIE_NORMAL_MSG_CODE(msg_code) |
CDNS_PCIE_MSG_NO_DATA;
writel(0, ep->irq_cpu_addr + offset);
}
static int cdns_pcie_ep_send_legacy_irq(struct cdns_pcie_ep *ep, u8 fn, u8 intx)
{
u16 cmd;
cmd = cdns_pcie_ep_fn_readw(&ep->pcie, fn, PCI_COMMAND);
if (cmd & PCI_COMMAND_INTX_DISABLE)
return -EINVAL;
cdns_pcie_ep_assert_intx(ep, fn, intx, true);
/*
* The mdelay() value was taken from dra7xx_pcie_raise_legacy_irq()
* from drivers/pci/dwc/pci-dra7xx.c
*/
mdelay(1);
cdns_pcie_ep_assert_intx(ep, fn, intx, false);
return 0;
}
static int cdns_pcie_ep_send_msi_irq(struct cdns_pcie_ep *ep, u8 fn,
u8 interrupt_num)
{
struct cdns_pcie *pcie = &ep->pcie;
u32 cap = CDNS_PCIE_EP_FUNC_MSI_CAP_OFFSET;
u16 flags, mme, data, data_mask;
u8 msi_count;
u64 pci_addr, pci_addr_mask = 0xff;
/* Check whether the MSI feature has been enabled by the PCI host. */
flags = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_FLAGS);
if (!(flags & PCI_MSI_FLAGS_ENABLE))
return -EINVAL;
/* Get the number of enabled MSIs */
mme = (flags & PCI_MSI_FLAGS_QSIZE) >> 4;
msi_count = 1 << mme;
if (!interrupt_num || interrupt_num > msi_count)
return -EINVAL;
/* Compute the data value to be written. */
data_mask = msi_count - 1;
data = cdns_pcie_ep_fn_readw(pcie, fn, cap + PCI_MSI_DATA_64);
data = (data & ~data_mask) | ((interrupt_num - 1) & data_mask);
/* Get the PCI address where to write the data into. */
pci_addr = cdns_pcie_ep_fn_readl(pcie, fn, cap + PCI_MSI_ADDRESS_HI);
pci_addr <<= 32;
pci_addr |= cdns_pcie_ep_fn_readl(pcie, fn, cap + PCI_MSI_ADDRESS_LO);
pci_addr &= GENMASK_ULL(63, 2);
/* Set the outbound region if needed. */
if (unlikely(ep->irq_pci_addr != (pci_addr & ~pci_addr_mask) ||
ep->irq_pci_fn != fn)) {
/* Last region was reserved for IRQ writes. */
cdns_pcie_set_outbound_region(pcie, fn, ep->max_regions - 1,
false,
ep->irq_phys_addr,
pci_addr & ~pci_addr_mask,
pci_addr_mask + 1);
ep->irq_pci_addr = (pci_addr & ~pci_addr_mask);
ep->irq_pci_fn = fn;
}
writew(data, ep->irq_cpu_addr + (pci_addr & pci_addr_mask));
return 0;
}
static int cdns_pcie_ep_raise_irq(struct pci_epc *epc, u8 fn,
enum pci_epc_irq_type type, u8 interrupt_num)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
switch (type) {
case PCI_EPC_IRQ_LEGACY:
return cdns_pcie_ep_send_legacy_irq(ep, fn, 0);
case PCI_EPC_IRQ_MSI:
return cdns_pcie_ep_send_msi_irq(ep, fn, interrupt_num);
default:
break;
}
return -EINVAL;
}
static int cdns_pcie_ep_start(struct pci_epc *epc)
{
struct cdns_pcie_ep *ep = epc_get_drvdata(epc);
struct cdns_pcie *pcie = &ep->pcie;
struct pci_epf *epf;
u32 cfg;
/*
* BIT(0) is hardwired to 1, hence function 0 is always enabled
* and can't be disabled anyway.
*/
cfg = BIT(0);
list_for_each_entry(epf, &epc->pci_epf, list)
cfg |= BIT(epf->func_no);
cdns_pcie_writel(pcie, CDNS_PCIE_LM_EP_FUNC_CFG, cfg);
/*
* The PCIe links are automatically established by the controller
* once for all at powerup: the software can neither start nor stop
* those links later at runtime.
*
* Then we only have to notify the EP core that our links are already
* established. However we don't call directly pci_epc_linkup() because
* we've already locked the epc->lock.
*/
list_for_each_entry(epf, &epc->pci_epf, list)
pci_epf_linkup(epf);
return 0;
}
static const struct pci_epc_ops cdns_pcie_epc_ops = {
.write_header = cdns_pcie_ep_write_header,
.set_bar = cdns_pcie_ep_set_bar,
.clear_bar = cdns_pcie_ep_clear_bar,
.map_addr = cdns_pcie_ep_map_addr,
.unmap_addr = cdns_pcie_ep_unmap_addr,
.set_msi = cdns_pcie_ep_set_msi,
.get_msi = cdns_pcie_ep_get_msi,
.raise_irq = cdns_pcie_ep_raise_irq,
.start = cdns_pcie_ep_start,
};
static const struct of_device_id cdns_pcie_ep_of_match[] = {
{ .compatible = "cdns,cdns-pcie-ep" },
{ },
};
static int cdns_pcie_ep_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct cdns_pcie_ep *ep;
struct cdns_pcie *pcie;
struct pci_epc *epc;
struct resource *res;
int ret;
ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);
if (!ep)
return -ENOMEM;
pcie = &ep->pcie;
pcie->is_rc = false;
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, "mem");
if (!res) {
dev_err(dev, "missing \"mem\"\n");
return -EINVAL;
}
pcie->mem_res = res;
ret = of_property_read_u32(np, "cdns,max-outbound-regions",
&ep->max_regions);
if (ret < 0) {
dev_err(dev, "missing \"cdns,max-outbound-regions\"\n");
return ret;
}
ep->ob_addr = devm_kzalloc(dev, ep->max_regions * sizeof(*ep->ob_addr),
GFP_KERNEL);
if (!ep->ob_addr)
return -ENOMEM;
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;
}
/* Disable all but function 0 (anyway BIT(0) is hardwired to 1). */
cdns_pcie_writel(pcie, CDNS_PCIE_LM_EP_FUNC_CFG, BIT(0));
epc = devm_pci_epc_create(dev, &cdns_pcie_epc_ops);
if (IS_ERR(epc)) {
dev_err(dev, "failed to create epc device\n");
ret = PTR_ERR(epc);
goto err_init;
}
epc_set_drvdata(epc, ep);
if (of_property_read_u8(np, "max-functions", &epc->max_functions) < 0)
epc->max_functions = 1;
ret = pci_epc_mem_init(epc, pcie->mem_res->start,
resource_size(pcie->mem_res));
if (ret < 0) {
dev_err(dev, "failed to initialize the memory space\n");
goto err_init;
}
ep->irq_cpu_addr = pci_epc_mem_alloc_addr(epc, &ep->irq_phys_addr,
SZ_128K);
if (!ep->irq_cpu_addr) {
dev_err(dev, "failed to reserve memory space for MSI\n");
ret = -ENOMEM;
goto free_epc_mem;
}
ep->irq_pci_addr = CDNS_PCIE_EP_IRQ_PCI_ADDR_NONE;
return 0;
free_epc_mem:
pci_epc_mem_exit(epc);
err_init:
pm_runtime_put_sync(dev);
err_get_sync:
pm_runtime_disable(dev);
return ret;
}
static void cdns_pcie_ep_shutdown(struct platform_device *pdev)
{
struct device *dev = &pdev->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);
/* The PCIe controller can't be disabled. */
}
static struct platform_driver cdns_pcie_ep_driver = {
.driver = {
.name = "cdns-pcie-ep",
.of_match_table = cdns_pcie_ep_of_match,
},
.probe = cdns_pcie_ep_probe,
.shutdown = cdns_pcie_ep_shutdown,
};
builtin_platform_driver(cdns_pcie_ep_driver);