leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

phy: amlogic: Add Amlogic AXG PCIE PHY Driver

Browse Source 
This adds support for the PCI PHY found in the Amlogic AXG SoC Family.
This will allow to mutualize code in pci-meson.c between AXG and G12A
SoC.

This PHY also uses and chains an analog PHY, which on AXG platform
is needed to have reliable PCIe communication.

Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
This commit is contained in:
Remi Pommarel 2020-01-24 00:29:42 +01:00 committed by Lorenzo Pieralisi
parent af3f5722d1
commit e2463559ff
3 changed files with 204 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
drivers/phy/amlogic/Kconfig
View File

@ -60,6 +60,17 @@ config PHY_MESON_G12A_USB3_PCIE
in Meson G12A SoCs.
If unsure, say N.
config PHY_MESON_AXG_PCIE
tristate "Meson AXG PCIE PHY driver"
default ARCH_MESON
depends on OF && (ARCH_MESON || COMPILE_TEST)
select GENERIC_PHY
select REGMAP_MMIO
help
Enable this to support the Meson MIPI + PCIE PHY found
in Meson AXG SoCs.
If unsure, say N.
config PHY_MESON_AXG_MIPI_PCIE_ANALOG
tristate "Meson AXG MIPI + PCIE analog PHY driver"
default ARCH_MESON

1
drivers/phy/amlogic/Makefile
View File

@ -4,4 +4,5 @@ obj-$(CONFIG_PHY_MESON_GXL_USB2) += phy-meson-gxl-usb2.o
obj-$(CONFIG_PHY_MESON_G12A_USB2) += phy-meson-g12a-usb2.o
obj-$(CONFIG_PHY_MESON_GXL_USB3) += phy-meson-gxl-usb3.o
obj-$(CONFIG_PHY_MESON_G12A_USB3_PCIE) += phy-meson-g12a-usb3-pcie.o
obj-$(CONFIG_PHY_MESON_AXG_PCIE) += phy-meson-axg-pcie.o
obj-$(CONFIG_PHY_MESON_AXG_MIPI_PCIE_ANALOG) += phy-meson-axg-mipi-pcie-analog.o

192
drivers/phy/amlogic/phy-meson-axg-pcie.c Normal file
View File

@ -0,0 +1,192 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Amlogic AXG PCIE PHY driver
*
* Copyright (C) 2020 Remi Pommarel <repk@triplefau.lt>
*/
#include <linux/module.h>
#include <linux/phy/phy.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/platform_device.h>
#include <linux/bitfield.h>
#include <dt-bindings/phy/phy.h>
#define MESON_PCIE_REG0 0x00
#define MESON_PCIE_COMMON_CLK BIT(4)
#define MESON_PCIE_PORT_SEL GENMASK(3, 2)
#define MESON_PCIE_CLK BIT(1)
#define MESON_PCIE_POWERDOWN BIT(0)
#define MESON_PCIE_TWO_X1 FIELD_PREP(MESON_PCIE_PORT_SEL, 0x3)
#define MESON_PCIE_COMMON_REF_CLK FIELD_PREP(MESON_PCIE_COMMON_CLK, 0x1)
#define MESON_PCIE_PHY_INIT (MESON_PCIE_TWO_X1 | \
MESON_PCIE_COMMON_REF_CLK)
#define MESON_PCIE_RESET_DELAY 500
struct phy_axg_pcie_priv {
struct phy *phy;
struct phy *analog;
struct regmap *regmap;
struct reset_control *reset;
};
static const struct regmap_config phy_axg_pcie_regmap_conf = {
.reg_bits = 8,
.val_bits = 32,
.reg_stride = 4,
.max_register = MESON_PCIE_REG0,
};
static int phy_axg_pcie_power_on(struct phy *phy)
{
struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
int ret;
ret = phy_power_on(priv->analog);
if (ret != 0)
return ret;
regmap_update_bits(priv->regmap, MESON_PCIE_REG0,
MESON_PCIE_POWERDOWN, 0);
return 0;
}
static int phy_axg_pcie_power_off(struct phy *phy)
{
struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
int ret;
ret = phy_power_off(priv->analog);
if (ret != 0)
return ret;
regmap_update_bits(priv->regmap, MESON_PCIE_REG0,
MESON_PCIE_POWERDOWN, 1);
return 0;
}
static int phy_axg_pcie_init(struct phy *phy)
{
struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
int ret;
ret = phy_init(priv->analog);
if (ret != 0)
return ret;
regmap_write(priv->regmap, MESON_PCIE_REG0, MESON_PCIE_PHY_INIT);
return reset_control_reset(priv->reset);
}
static int phy_axg_pcie_exit(struct phy *phy)
{
struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
int ret;
ret = phy_exit(priv->analog);
if (ret != 0)
return ret;
return reset_control_reset(priv->reset);
}
static int phy_axg_pcie_reset(struct phy *phy)
{
struct phy_axg_pcie_priv *priv = phy_get_drvdata(phy);
int ret = 0;
ret = phy_reset(priv->analog);
if (ret != 0)
goto out;
ret = reset_control_assert(priv->reset);
if (ret != 0)
goto out;
udelay(MESON_PCIE_RESET_DELAY);
ret = reset_control_deassert(priv->reset);
if (ret != 0)
goto out;
udelay(MESON_PCIE_RESET_DELAY);
out:
return ret;
}
static const struct phy_ops phy_axg_pcie_ops = {
.init = phy_axg_pcie_init,
.exit = phy_axg_pcie_exit,
.power_on = phy_axg_pcie_power_on,
.power_off = phy_axg_pcie_power_off,
.reset = phy_axg_pcie_reset,
.owner = THIS_MODULE,
};
static int phy_axg_pcie_probe(struct platform_device *pdev)
{
struct phy_provider *pphy;
struct device *dev = &pdev->dev;
struct phy_axg_pcie_priv *priv;
struct device_node *np = dev->of_node;
struct resource *res;
void __iomem *base;
int ret;
priv = devm_kmalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->phy = devm_phy_create(dev, np, &phy_axg_pcie_ops);
if (IS_ERR(priv->phy)) {
ret = PTR_ERR(priv->phy);
if (ret != -EPROBE_DEFER)
dev_err(dev, "failed to create PHY\n");
return ret;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(dev, res);
if (IS_ERR(base))
return PTR_ERR(base);
priv->regmap = devm_regmap_init_mmio(dev, base,
&phy_axg_pcie_regmap_conf);
if (IS_ERR(priv->regmap))
return PTR_ERR(priv->regmap);
priv->reset = devm_reset_control_array_get(dev, false, false);
if (IS_ERR(priv->reset))
return PTR_ERR(priv->reset);
priv->analog = devm_phy_get(dev, "analog");
if (IS_ERR(priv->analog))
return PTR_ERR(priv->analog);
phy_set_drvdata(priv->phy, priv);
dev_set_drvdata(dev, priv);
pphy = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
return PTR_ERR_OR_ZERO(pphy);
}
static const struct of_device_id phy_axg_pcie_of_match[] = {
{
.compatible = "amlogic,axg-pcie-phy",
},
{ },
};
MODULE_DEVICE_TABLE(of, phy_axg_pcie_of_match);
static struct platform_driver phy_axg_pcie_driver = {
.probe = phy_axg_pcie_probe,
.driver = {
.name = "phy-axg-pcie",
.of_match_table = phy_axg_pcie_of_match,
},
};
module_platform_driver(phy_axg_pcie_driver);
MODULE_AUTHOR("Remi Pommarel <repk@triplefau.lt>");
MODULE_DESCRIPTION("Amlogic AXG PCIE PHY driver");
MODULE_LICENSE("GPL v2");