u-boot/drivers/pci/pcie_phytium.c
liu hao e3aafef4cf arm: add initial support for the Phytium Durian Board
This adds platform code and the device tree for the Phytium Durian Board.
The initial support comprises the UART and the PCIE.

Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Kever Yang <kever.yang@rock-chips.com>
Cc: Tom Rini <trini@konsulko.com>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>

Signed-off-by: Steven Hao <liuhao@phytium.com.cn>
2019-11-07 18:01:13 -05:00

200 lines
5.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Phytium PCIE host driver
*
* Heavily based on drivers/pci/pcie_xilinx.c
*
* Copyright (C) 2019
*/
#include <common.h>
#include <dm.h>
#include <pci.h>
#include <asm/io.h>
/**
* struct phytium_pcie - phytium PCIe controller state
* @cfg_base: The base address of memory mapped configuration space
*/
struct phytium_pcie {
void *cfg_base;
};
/*
* phytium_pci_skip_dev()
* @parent: Identifies the PCIe device to access
*
* Checks whether the parent of the PCIe device is bridge
*
* Return: true if it is bridge, else false.
*/
static int phytium_pci_skip_dev(pci_dev_t parent)
{
unsigned char pos, id;
unsigned long addr = 0x40000000;
unsigned short capreg;
unsigned char port_type;
addr += PCI_BUS(parent) << 20;
addr += PCI_DEV(parent) << 15;
addr += PCI_FUNC(parent) << 12;
pos = 0x34;
while (1) {
pos = readb(addr + pos);
if (pos < 0x40)
break;
pos &= ~3;
id = readb(addr + pos);
if (id == 0xff)
break;
if (id == 0x10) {
capreg = readw(addr + pos + 2);
port_type = (capreg >> 4) & 0xf;
if (port_type == 0x6 || port_type == 0x4)
return 1;
else
return 0;
}
pos += 1;
}
return 0;
}
/**
* pci_phytium_conf_address() - Calculate the address of a config access
* @bus: Pointer to the PCI bus
* @bdf: Identifies the PCIe device to access
* @offset: The offset into the device's configuration space
* @paddress: Pointer to the pointer to write the calculates address to
*
* Calculates the address that should be accessed to perform a PCIe
* configuration space access for a given device identified by the PCIe
* controller device @pcie and the bus, device & function numbers in @bdf. If
* access to the device is not valid then the function will return an error
* code. Otherwise the address to access will be written to the pointer pointed
* to by @paddress.
*/
static int pci_phytium_conf_address(struct udevice *bus, pci_dev_t bdf,
uint offset,
void **paddress)
{
struct phytium_pcie *pcie = dev_get_priv(bus);
void *addr;
pci_dev_t bdf_parent;
unsigned int bus_no = PCI_BUS(bdf);
unsigned int dev_no = PCI_DEV(bdf);
bdf_parent = PCI_BDF((bus_no - 1), 0, 0);
addr = pcie->cfg_base;
addr += PCI_BUS(bdf) << 20;
addr += PCI_DEV(bdf) << 15;
addr += PCI_FUNC(bdf) << 12;
if (bus_no > 0 && dev_no > 0) {
if ((readb(addr + PCI_HEADER_TYPE) & 0x7f) !=
PCI_HEADER_TYPE_BRIDGE)
return -ENODEV;
if (phytium_pci_skip_dev(bdf_parent))
return -ENODEV;
}
addr += offset;
*paddress = addr;
return 0;
}
/**
* pci_phytium_read_config() - Read from configuration space
* @bus: Pointer to the PCI bus
* @bdf: Identifies the PCIe device to access
* @offset: The offset into the device's configuration space
* @valuep: A pointer at which to store the read value
* @size: Indicates the size of access to perform
*
* Read a value of size @size from offset @offset within the configuration
* space of the device identified by the bus, device & function numbers in @bdf
* on the PCI bus @bus.
*/
static int pci_phytium_read_config(struct udevice *bus, pci_dev_t bdf,
uint offset, ulong *valuep,
enum pci_size_t size)
{
return pci_generic_mmap_read_config(bus, pci_phytium_conf_address,
bdf, offset, valuep, size);
}
/**
* pci_phytium_write_config() - Write to configuration space
* @bus: Pointer to the PCI bus
* @bdf: Identifies the PCIe device to access
* @offset: The offset into the device's configuration space
* @value: The value to write
* @size: Indicates the size of access to perform
*
* Write the value @value of size @size from offset @offset within the
* configuration space of the device identified by the bus, device & function
* numbers in @bdf on the PCI bus @bus.
*/
static int pci_phytium_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, pci_phytium_conf_address,
bdf, offset, value, size);
}
/**
* pci_phytium_ofdata_to_platdata() - Translate from DT to device state
* @dev: A pointer to the device being operated on
*
* Translate relevant data from the device tree pertaining to device @dev into
* state that the driver will later make use of. This state is stored in the
* device's private data structure.
*
* Return: 0 on success, else -EINVAL
*/
static int pci_phytium_ofdata_to_platdata(struct udevice *dev)
{
struct phytium_pcie *pcie = dev_get_priv(dev);
struct fdt_resource reg_res;
DECLARE_GLOBAL_DATA_PTR;
int err;
err = fdt_get_resource(gd->fdt_blob, dev_of_offset(dev), "reg",
0, &reg_res);
if (err < 0) {
pr_err("\"reg\" resource not found\n");
return err;
}
pcie->cfg_base = map_physmem(reg_res.start,
fdt_resource_size(&reg_res),
MAP_NOCACHE);
return 0;
}
static const struct dm_pci_ops pci_phytium_ops = {
.read_config = pci_phytium_read_config,
.write_config = pci_phytium_write_config,
};
static const struct udevice_id pci_phytium_ids[] = {
{ .compatible = "phytium,pcie-host-1.0" },
{ }
};
U_BOOT_DRIVER(pci_phytium) = {
.name = "pci_phytium",
.id = UCLASS_PCI,
.of_match = pci_phytium_ids,
.ops = &pci_phytium_ops,
.ofdata_to_platdata = pci_phytium_ofdata_to_platdata,
.priv_auto_alloc_size = sizeof(struct phytium_pcie),
};