u-boot/drivers/phy/phy-bcm-sr-pcie.c

178 lines
4.4 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2019 Broadcom
*/
#include <common.h>
#include <dm.h>
#include <generic-phy.h>
#include <asm/io.h>
#include <linux/bitops.h>
/* we have up to 8 PAXB based RC. The 9th one is always PAXC */
#define SR_NR_PCIE_PHYS 8
#define PCIE_PIPEMUX_CFG_OFFSET 0x10c
#define PCIE_PIPEMUX_SELECT_STRAP GENMASK(3, 0)
#define CDRU_STRAP_DATA_LSW_OFFSET 0x5c
#define PCIE_PIPEMUX_SHIFT 19
#define PCIE_PIPEMUX_MASK GENMASK(3, 0)
/**
* struct sr_pcie_phy_core - Stingray PCIe PHY core control
*
* @dev: pointer to device
* @base: base register of PCIe SS
* @cdru: CDRU base address
* @pipemux: pipemuex strap
*/
struct sr_pcie_phy_core {
struct udevice *dev;
void __iomem *base;
void __iomem *cdru;
u32 pipemux;
};
/*
* PCIe PIPEMUX lookup table
*
* Each array index represents a PIPEMUX strap setting
* The array element represents a bitmap where a set bit means the PCIe
* core and associated serdes has been enabled as RC and is available for use
*/
static const u8 pipemux_table[] = {
/* PIPEMUX = 0, EP 1x16 */
0x00,
/* PIPEMUX = 1, EP 1x8 + RC 1x8, core 7 */
0x80,
/* PIPEMUX = 2, EP 4x4 */
0x00,
/* PIPEMUX = 3, RC 2x8, cores 0, 7 */
0x81,
/* PIPEMUX = 4, RC 4x4, cores 0, 1, 6, 7 */
0xc3,
/* PIPEMUX = 5, RC 8x2, all 8 cores */
0xff,
/* PIPEMUX = 6, RC 3x4 + 2x2, cores 0, 2, 3, 6, 7 */
0xcd,
/* PIPEMUX = 7, RC 1x4 + 6x2, cores 0, 2, 3, 4, 5, 6, 7 */
0xfd,
/* PIPEMUX = 8, EP 1x8 + RC 4x2, cores 4, 5, 6, 7 */
0xf0,
/* PIPEMUX = 9, EP 1x8 + RC 2x4, cores 6, 7 */
0xc0,
/* PIPEMUX = 10, EP 2x4 + RC 2x4, cores 1, 6 */
0x42,
/* PIPEMUX = 11, EP 2x4 + RC 4x2, cores 2, 3, 4, 5 */
0x3c,
/* PIPEMUX = 12, EP 1x4 + RC 6x2, cores 2, 3, 4, 5, 6, 7 */
0xfc,
/* PIPEMUX = 13, RC 2x4 + RC 1x4 + 2x2, cores 2, 3, 6 */
0x4c,
};
/*
* Return true if the strap setting is valid
*/
static bool pipemux_strap_is_valid(u32 pipemux)
{
return !!(pipemux < ARRAY_SIZE(pipemux_table));
}
/*
* Read the PCIe PIPEMUX from strap
*/
static u32 pipemux_strap_read(struct sr_pcie_phy_core *core)
{
u32 pipemux;
/*
* Read PIPEMUX configuration register to determine the pipemux setting
*
* In the case when the value indicates using HW strap, fall back to
* use HW strap
*/
pipemux = readl(core->base + PCIE_PIPEMUX_CFG_OFFSET);
pipemux &= PCIE_PIPEMUX_MASK;
if (pipemux == PCIE_PIPEMUX_SELECT_STRAP) {
pipemux = readl(core->cdru + CDRU_STRAP_DATA_LSW_OFFSET);
pipemux >>= PCIE_PIPEMUX_SHIFT;
pipemux &= PCIE_PIPEMUX_MASK;
}
return pipemux;
}
static int sr_pcie_phy_init(struct phy *phy)
{
struct sr_pcie_phy_core *core = dev_get_priv(phy->dev);
unsigned int core_idx = phy->id;
debug("%s %lx\n", __func__, phy->id);
/*
* Check whether this PHY is for root complex or not. If yes, return
* zero so the host driver can proceed to enumeration. If not, return
* an error and that will force the host driver to bail out
*/
if (!!((pipemux_table[core->pipemux] >> core_idx) & 0x1))
return 0;
return -ENODEV;
}
static int sr_pcie_phy_xlate(struct phy *phy, struct ofnode_phandle_args *args)
{
debug("%s %d\n", __func__, args->args[0]);
if (args->args_count && args->args[0] < SR_NR_PCIE_PHYS)
phy->id = args->args[0];
else
return -ENODEV;
return 0;
}
static const struct phy_ops sr_pcie_phy_ops = {
.of_xlate = sr_pcie_phy_xlate,
.init = sr_pcie_phy_init,
};
static int sr_pcie_phy_probe(struct udevice *dev)
{
struct sr_pcie_phy_core *core = dev_get_priv(dev);
core->dev = dev;
core->base = (void __iomem *)devfdt_get_addr_name(dev, "reg_base");
core->cdru = (void __iomem *)devfdt_get_addr_name(dev, "cdru_base");
debug("ip base %p\n", core->base);
debug("cdru base %p\n", core->cdru);
/* read the PCIe PIPEMUX strap setting */
core->pipemux = pipemux_strap_read(core);
if (!pipemux_strap_is_valid(core->pipemux)) {
pr_err("invalid PCIe PIPEMUX strap %u\n", core->pipemux);
return -EIO;
}
debug("%s %#x\n", __func__, core->pipemux);
pr_info("Stingray PCIe PHY driver initialized\n");
return 0;
}
static const struct udevice_id sr_pcie_phy_match_table[] = {
{ .compatible = "brcm,sr-pcie-phy" },
{ }
};
U_BOOT_DRIVER(sr_pcie_phy) = {
.name = "sr-pcie-phy",
.id = UCLASS_PHY,
.probe = sr_pcie_phy_probe,
.of_match = sr_pcie_phy_match_table,
.ops = &sr_pcie_phy_ops,
.plat_auto = sizeof(struct sr_pcie_phy_core),
.priv_auto = sizeof(struct sr_pcie_phy_core),
};