linux/drivers/phy/allwinner/phy-sun6i-mipi-dphy.c
Paul Kocialkowski 74d0cd4786 phy: allwinner: phy-sun6i-mipi-dphy: Support D-PHY Rx mode for MIPI CSI-2
The Allwinner A31 D-PHY supports both Rx and Tx modes. While the latter
is already supported and used for MIPI DSI this adds support for the
former, to be used with MIPI CSI-2.

This implementation is inspired by Allwinner's V3s Linux SDK
implementation, which was used as a documentation base.

It uses the direction dt property to distinguish between tx and rx
directions.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Link: https://lore.kernel.org/r/20220415152138.635525-3-paul.kocialkowski@bootlin.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
2022-04-20 14:40:12 +05:30

475 lines
14 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2016 Allwinnertech Co., Ltd.
* Copyright (C) 2017-2018 Bootlin
*
* Maxime Ripard <maxime.ripard@free-electrons.com>
*/
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset.h>
#include <linux/phy/phy.h>
#include <linux/phy/phy-mipi-dphy.h>
#define SUN6I_DPHY_GCTL_REG 0x00
#define SUN6I_DPHY_GCTL_LANE_NUM(n) ((((n) - 1) & 3) << 4)
#define SUN6I_DPHY_GCTL_EN BIT(0)
#define SUN6I_DPHY_TX_CTL_REG 0x04
#define SUN6I_DPHY_TX_CTL_HS_TX_CLK_CONT BIT(28)
#define SUN6I_DPHY_RX_CTL_REG 0x08
#define SUN6I_DPHY_RX_CTL_EN_DBC BIT(31)
#define SUN6I_DPHY_RX_CTL_RX_CLK_FORCE BIT(24)
#define SUN6I_DPHY_RX_CTL_RX_D3_FORCE BIT(23)
#define SUN6I_DPHY_RX_CTL_RX_D2_FORCE BIT(22)
#define SUN6I_DPHY_RX_CTL_RX_D1_FORCE BIT(21)
#define SUN6I_DPHY_RX_CTL_RX_D0_FORCE BIT(20)
#define SUN6I_DPHY_TX_TIME0_REG 0x10
#define SUN6I_DPHY_TX_TIME0_HS_TRAIL(n) (((n) & 0xff) << 24)
#define SUN6I_DPHY_TX_TIME0_HS_PREPARE(n) (((n) & 0xff) << 16)
#define SUN6I_DPHY_TX_TIME0_LP_CLK_DIV(n) ((n) & 0xff)
#define SUN6I_DPHY_TX_TIME1_REG 0x14
#define SUN6I_DPHY_TX_TIME1_CLK_POST(n) (((n) & 0xff) << 24)
#define SUN6I_DPHY_TX_TIME1_CLK_PRE(n) (((n) & 0xff) << 16)
#define SUN6I_DPHY_TX_TIME1_CLK_ZERO(n) (((n) & 0xff) << 8)
#define SUN6I_DPHY_TX_TIME1_CLK_PREPARE(n) ((n) & 0xff)
#define SUN6I_DPHY_TX_TIME2_REG 0x18
#define SUN6I_DPHY_TX_TIME2_CLK_TRAIL(n) ((n) & 0xff)
#define SUN6I_DPHY_TX_TIME3_REG 0x1c
#define SUN6I_DPHY_TX_TIME4_REG 0x20
#define SUN6I_DPHY_TX_TIME4_HS_TX_ANA1(n) (((n) & 0xff) << 8)
#define SUN6I_DPHY_TX_TIME4_HS_TX_ANA0(n) ((n) & 0xff)
#define SUN6I_DPHY_RX_TIME0_REG 0x30
#define SUN6I_DPHY_RX_TIME0_HS_RX_SYNC(n) (((n) & 0xff) << 24)
#define SUN6I_DPHY_RX_TIME0_HS_RX_CLK_MISS(n) (((n) & 0xff) << 16)
#define SUN6I_DPHY_RX_TIME0_LP_RX(n) (((n) & 0xff) << 8)
#define SUN6I_DPHY_RX_TIME1_REG 0x34
#define SUN6I_DPHY_RX_TIME1_RX_DLY(n) (((n) & 0xfff) << 20)
#define SUN6I_DPHY_RX_TIME1_LP_RX_ULPS_WP(n) ((n) & 0xfffff)
#define SUN6I_DPHY_RX_TIME2_REG 0x38
#define SUN6I_DPHY_RX_TIME2_HS_RX_ANA1(n) (((n) & 0xff) << 8)
#define SUN6I_DPHY_RX_TIME2_HS_RX_ANA0(n) ((n) & 0xff)
#define SUN6I_DPHY_RX_TIME3_REG 0x40
#define SUN6I_DPHY_RX_TIME3_LPRST_DLY(n) (((n) & 0xffff) << 16)
#define SUN6I_DPHY_ANA0_REG 0x4c
#define SUN6I_DPHY_ANA0_REG_PWS BIT(31)
#define SUN6I_DPHY_ANA0_REG_DMPC BIT(28)
#define SUN6I_DPHY_ANA0_REG_DMPD(n) (((n) & 0xf) << 24)
#define SUN6I_DPHY_ANA0_REG_SLV(n) (((n) & 7) << 12)
#define SUN6I_DPHY_ANA0_REG_DEN(n) (((n) & 0xf) << 8)
#define SUN6I_DPHY_ANA0_REG_SFB(n) (((n) & 3) << 2)
#define SUN6I_DPHY_ANA1_REG 0x50
#define SUN6I_DPHY_ANA1_REG_VTTMODE BIT(31)
#define SUN6I_DPHY_ANA1_REG_CSMPS(n) (((n) & 3) << 28)
#define SUN6I_DPHY_ANA1_REG_SVTT(n) (((n) & 0xf) << 24)
#define SUN6I_DPHY_ANA2_REG 0x54
#define SUN6I_DPHY_ANA2_EN_P2S_CPU(n) (((n) & 0xf) << 24)
#define SUN6I_DPHY_ANA2_EN_P2S_CPU_MASK GENMASK(27, 24)
#define SUN6I_DPHY_ANA2_EN_CK_CPU BIT(4)
#define SUN6I_DPHY_ANA2_REG_ENIB BIT(1)
#define SUN6I_DPHY_ANA3_REG 0x58
#define SUN6I_DPHY_ANA3_EN_VTTD(n) (((n) & 0xf) << 28)
#define SUN6I_DPHY_ANA3_EN_VTTD_MASK GENMASK(31, 28)
#define SUN6I_DPHY_ANA3_EN_VTTC BIT(27)
#define SUN6I_DPHY_ANA3_EN_DIV BIT(26)
#define SUN6I_DPHY_ANA3_EN_LDOC BIT(25)
#define SUN6I_DPHY_ANA3_EN_LDOD BIT(24)
#define SUN6I_DPHY_ANA3_EN_LDOR BIT(18)
#define SUN6I_DPHY_ANA4_REG 0x5c
#define SUN6I_DPHY_ANA4_REG_DMPLVC BIT(24)
#define SUN6I_DPHY_ANA4_REG_DMPLVD(n) (((n) & 0xf) << 20)
#define SUN6I_DPHY_ANA4_REG_CKDV(n) (((n) & 0x1f) << 12)
#define SUN6I_DPHY_ANA4_REG_TMSC(n) (((n) & 3) << 10)
#define SUN6I_DPHY_ANA4_REG_TMSD(n) (((n) & 3) << 8)
#define SUN6I_DPHY_ANA4_REG_TXDNSC(n) (((n) & 3) << 6)
#define SUN6I_DPHY_ANA4_REG_TXDNSD(n) (((n) & 3) << 4)
#define SUN6I_DPHY_ANA4_REG_TXPUSC(n) (((n) & 3) << 2)
#define SUN6I_DPHY_ANA4_REG_TXPUSD(n) ((n) & 3)
#define SUN6I_DPHY_DBG5_REG 0xf4
enum sun6i_dphy_direction {
SUN6I_DPHY_DIRECTION_TX,
SUN6I_DPHY_DIRECTION_RX,
};
struct sun6i_dphy {
struct clk *bus_clk;
struct clk *mod_clk;
struct regmap *regs;
struct reset_control *reset;
struct phy *phy;
struct phy_configure_opts_mipi_dphy config;
enum sun6i_dphy_direction direction;
};
static int sun6i_dphy_init(struct phy *phy)
{
struct sun6i_dphy *dphy = phy_get_drvdata(phy);
reset_control_deassert(dphy->reset);
clk_prepare_enable(dphy->mod_clk);
clk_set_rate_exclusive(dphy->mod_clk, 150000000);
return 0;
}
static int sun6i_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
{
struct sun6i_dphy *dphy = phy_get_drvdata(phy);
int ret;
ret = phy_mipi_dphy_config_validate(&opts->mipi_dphy);
if (ret)
return ret;
memcpy(&dphy->config, opts, sizeof(dphy->config));
return 0;
}
static int sun6i_dphy_tx_power_on(struct sun6i_dphy *dphy)
{
u8 lanes_mask = GENMASK(dphy->config.lanes - 1, 0);
regmap_write(dphy->regs, SUN6I_DPHY_TX_CTL_REG,
SUN6I_DPHY_TX_CTL_HS_TX_CLK_CONT);
regmap_write(dphy->regs, SUN6I_DPHY_TX_TIME0_REG,
SUN6I_DPHY_TX_TIME0_LP_CLK_DIV(14) |
SUN6I_DPHY_TX_TIME0_HS_PREPARE(6) |
SUN6I_DPHY_TX_TIME0_HS_TRAIL(10));
regmap_write(dphy->regs, SUN6I_DPHY_TX_TIME1_REG,
SUN6I_DPHY_TX_TIME1_CLK_PREPARE(7) |
SUN6I_DPHY_TX_TIME1_CLK_ZERO(50) |
SUN6I_DPHY_TX_TIME1_CLK_PRE(3) |
SUN6I_DPHY_TX_TIME1_CLK_POST(10));
regmap_write(dphy->regs, SUN6I_DPHY_TX_TIME2_REG,
SUN6I_DPHY_TX_TIME2_CLK_TRAIL(30));
regmap_write(dphy->regs, SUN6I_DPHY_TX_TIME3_REG, 0);
regmap_write(dphy->regs, SUN6I_DPHY_TX_TIME4_REG,
SUN6I_DPHY_TX_TIME4_HS_TX_ANA0(3) |
SUN6I_DPHY_TX_TIME4_HS_TX_ANA1(3));
regmap_write(dphy->regs, SUN6I_DPHY_GCTL_REG,
SUN6I_DPHY_GCTL_LANE_NUM(dphy->config.lanes) |
SUN6I_DPHY_GCTL_EN);
regmap_write(dphy->regs, SUN6I_DPHY_ANA0_REG,
SUN6I_DPHY_ANA0_REG_PWS |
SUN6I_DPHY_ANA0_REG_DMPC |
SUN6I_DPHY_ANA0_REG_SLV(7) |
SUN6I_DPHY_ANA0_REG_DMPD(lanes_mask) |
SUN6I_DPHY_ANA0_REG_DEN(lanes_mask));
regmap_write(dphy->regs, SUN6I_DPHY_ANA1_REG,
SUN6I_DPHY_ANA1_REG_CSMPS(1) |
SUN6I_DPHY_ANA1_REG_SVTT(7));
regmap_write(dphy->regs, SUN6I_DPHY_ANA4_REG,
SUN6I_DPHY_ANA4_REG_CKDV(1) |
SUN6I_DPHY_ANA4_REG_TMSC(1) |
SUN6I_DPHY_ANA4_REG_TMSD(1) |
SUN6I_DPHY_ANA4_REG_TXDNSC(1) |
SUN6I_DPHY_ANA4_REG_TXDNSD(1) |
SUN6I_DPHY_ANA4_REG_TXPUSC(1) |
SUN6I_DPHY_ANA4_REG_TXPUSD(1) |
SUN6I_DPHY_ANA4_REG_DMPLVC |
SUN6I_DPHY_ANA4_REG_DMPLVD(lanes_mask));
regmap_write(dphy->regs, SUN6I_DPHY_ANA2_REG,
SUN6I_DPHY_ANA2_REG_ENIB);
udelay(5);
regmap_write(dphy->regs, SUN6I_DPHY_ANA3_REG,
SUN6I_DPHY_ANA3_EN_LDOR |
SUN6I_DPHY_ANA3_EN_LDOC |
SUN6I_DPHY_ANA3_EN_LDOD);
udelay(1);
regmap_update_bits(dphy->regs, SUN6I_DPHY_ANA3_REG,
SUN6I_DPHY_ANA3_EN_VTTC |
SUN6I_DPHY_ANA3_EN_VTTD_MASK,
SUN6I_DPHY_ANA3_EN_VTTC |
SUN6I_DPHY_ANA3_EN_VTTD(lanes_mask));
udelay(1);
regmap_update_bits(dphy->regs, SUN6I_DPHY_ANA3_REG,
SUN6I_DPHY_ANA3_EN_DIV,
SUN6I_DPHY_ANA3_EN_DIV);
udelay(1);
regmap_update_bits(dphy->regs, SUN6I_DPHY_ANA2_REG,
SUN6I_DPHY_ANA2_EN_CK_CPU,
SUN6I_DPHY_ANA2_EN_CK_CPU);
udelay(1);
regmap_update_bits(dphy->regs, SUN6I_DPHY_ANA1_REG,
SUN6I_DPHY_ANA1_REG_VTTMODE,
SUN6I_DPHY_ANA1_REG_VTTMODE);
regmap_update_bits(dphy->regs, SUN6I_DPHY_ANA2_REG,
SUN6I_DPHY_ANA2_EN_P2S_CPU_MASK,
SUN6I_DPHY_ANA2_EN_P2S_CPU(lanes_mask));
return 0;
}
static int sun6i_dphy_rx_power_on(struct sun6i_dphy *dphy)
{
/* Physical clock rate is actually half of symbol rate with DDR. */
unsigned long mipi_symbol_rate = dphy->config.hs_clk_rate;
unsigned long dphy_clk_rate;
unsigned int rx_dly;
unsigned int lprst_dly;
u32 value;
dphy_clk_rate = clk_get_rate(dphy->mod_clk);
if (!dphy_clk_rate)
return -EINVAL;
/* Hardcoded timing parameters from the Allwinner BSP. */
regmap_write(dphy->regs, SUN6I_DPHY_RX_TIME0_REG,
SUN6I_DPHY_RX_TIME0_HS_RX_SYNC(255) |
SUN6I_DPHY_RX_TIME0_HS_RX_CLK_MISS(255) |
SUN6I_DPHY_RX_TIME0_LP_RX(255));
/*
* Formula from the Allwinner BSP, with hardcoded coefficients
* (probably internal divider/multiplier).
*/
rx_dly = 8 * (unsigned int)(dphy_clk_rate / (mipi_symbol_rate / 8));
/*
* The Allwinner BSP has an alternative formula for LP_RX_ULPS_WP:
* lp_ulps_wp_cnt = lp_ulps_wp_ms * lp_clk / 1000
* but does not use it and hardcodes 255 instead.
*/
regmap_write(dphy->regs, SUN6I_DPHY_RX_TIME1_REG,
SUN6I_DPHY_RX_TIME1_RX_DLY(rx_dly) |
SUN6I_DPHY_RX_TIME1_LP_RX_ULPS_WP(255));
/* HS_RX_ANA0 value is hardcoded in the Allwinner BSP. */
regmap_write(dphy->regs, SUN6I_DPHY_RX_TIME2_REG,
SUN6I_DPHY_RX_TIME2_HS_RX_ANA0(4));
/*
* Formula from the Allwinner BSP, with hardcoded coefficients
* (probably internal divider/multiplier).
*/
lprst_dly = 4 * (unsigned int)(dphy_clk_rate / (mipi_symbol_rate / 2));
regmap_write(dphy->regs, SUN6I_DPHY_RX_TIME3_REG,
SUN6I_DPHY_RX_TIME3_LPRST_DLY(lprst_dly));
/* Analog parameters are hardcoded in the Allwinner BSP. */
regmap_write(dphy->regs, SUN6I_DPHY_ANA0_REG,
SUN6I_DPHY_ANA0_REG_PWS |
SUN6I_DPHY_ANA0_REG_SLV(7) |
SUN6I_DPHY_ANA0_REG_SFB(2));
regmap_write(dphy->regs, SUN6I_DPHY_ANA1_REG,
SUN6I_DPHY_ANA1_REG_SVTT(4));
regmap_write(dphy->regs, SUN6I_DPHY_ANA4_REG,
SUN6I_DPHY_ANA4_REG_DMPLVC |
SUN6I_DPHY_ANA4_REG_DMPLVD(1));
regmap_write(dphy->regs, SUN6I_DPHY_ANA2_REG,
SUN6I_DPHY_ANA2_REG_ENIB);
regmap_write(dphy->regs, SUN6I_DPHY_ANA3_REG,
SUN6I_DPHY_ANA3_EN_LDOR |
SUN6I_DPHY_ANA3_EN_LDOC |
SUN6I_DPHY_ANA3_EN_LDOD);
/*
* Delay comes from the Allwinner BSP, likely for internal regulator
* ramp-up.
*/
udelay(3);
value = SUN6I_DPHY_RX_CTL_EN_DBC | SUN6I_DPHY_RX_CTL_RX_CLK_FORCE;
/*
* Rx data lane force-enable bits are used as regular RX enable by the
* Allwinner BSP.
*/
if (dphy->config.lanes >= 1)
value |= SUN6I_DPHY_RX_CTL_RX_D0_FORCE;
if (dphy->config.lanes >= 2)
value |= SUN6I_DPHY_RX_CTL_RX_D1_FORCE;
if (dphy->config.lanes >= 3)
value |= SUN6I_DPHY_RX_CTL_RX_D2_FORCE;
if (dphy->config.lanes == 4)
value |= SUN6I_DPHY_RX_CTL_RX_D3_FORCE;
regmap_write(dphy->regs, SUN6I_DPHY_RX_CTL_REG, value);
regmap_write(dphy->regs, SUN6I_DPHY_GCTL_REG,
SUN6I_DPHY_GCTL_LANE_NUM(dphy->config.lanes) |
SUN6I_DPHY_GCTL_EN);
return 0;
}
static int sun6i_dphy_power_on(struct phy *phy)
{
struct sun6i_dphy *dphy = phy_get_drvdata(phy);
switch (dphy->direction) {
case SUN6I_DPHY_DIRECTION_TX:
return sun6i_dphy_tx_power_on(dphy);
case SUN6I_DPHY_DIRECTION_RX:
return sun6i_dphy_rx_power_on(dphy);
default:
return -EINVAL;
}
}
static int sun6i_dphy_power_off(struct phy *phy)
{
struct sun6i_dphy *dphy = phy_get_drvdata(phy);
regmap_write(dphy->regs, SUN6I_DPHY_GCTL_REG, 0);
regmap_write(dphy->regs, SUN6I_DPHY_ANA0_REG, 0);
regmap_write(dphy->regs, SUN6I_DPHY_ANA1_REG, 0);
regmap_write(dphy->regs, SUN6I_DPHY_ANA2_REG, 0);
regmap_write(dphy->regs, SUN6I_DPHY_ANA3_REG, 0);
regmap_write(dphy->regs, SUN6I_DPHY_ANA4_REG, 0);
return 0;
}
static int sun6i_dphy_exit(struct phy *phy)
{
struct sun6i_dphy *dphy = phy_get_drvdata(phy);
clk_rate_exclusive_put(dphy->mod_clk);
clk_disable_unprepare(dphy->mod_clk);
reset_control_assert(dphy->reset);
return 0;
}
static const struct phy_ops sun6i_dphy_ops = {
.configure = sun6i_dphy_configure,
.power_on = sun6i_dphy_power_on,
.power_off = sun6i_dphy_power_off,
.init = sun6i_dphy_init,
.exit = sun6i_dphy_exit,
};
static const struct regmap_config sun6i_dphy_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
.max_register = SUN6I_DPHY_DBG5_REG,
.name = "mipi-dphy",
};
static int sun6i_dphy_probe(struct platform_device *pdev)
{
struct phy_provider *phy_provider;
struct sun6i_dphy *dphy;
const char *direction;
void __iomem *regs;
int ret;
dphy = devm_kzalloc(&pdev->dev, sizeof(*dphy), GFP_KERNEL);
if (!dphy)
return -ENOMEM;
regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(regs)) {
dev_err(&pdev->dev, "Couldn't map the DPHY encoder registers\n");
return PTR_ERR(regs);
}
dphy->regs = devm_regmap_init_mmio_clk(&pdev->dev, "bus",
regs, &sun6i_dphy_regmap_config);
if (IS_ERR(dphy->regs)) {
dev_err(&pdev->dev, "Couldn't create the DPHY encoder regmap\n");
return PTR_ERR(dphy->regs);
}
dphy->reset = devm_reset_control_get_shared(&pdev->dev, NULL);
if (IS_ERR(dphy->reset)) {
dev_err(&pdev->dev, "Couldn't get our reset line\n");
return PTR_ERR(dphy->reset);
}
dphy->mod_clk = devm_clk_get(&pdev->dev, "mod");
if (IS_ERR(dphy->mod_clk)) {
dev_err(&pdev->dev, "Couldn't get the DPHY mod clock\n");
return PTR_ERR(dphy->mod_clk);
}
dphy->phy = devm_phy_create(&pdev->dev, NULL, &sun6i_dphy_ops);
if (IS_ERR(dphy->phy)) {
dev_err(&pdev->dev, "failed to create PHY\n");
return PTR_ERR(dphy->phy);
}
dphy->direction = SUN6I_DPHY_DIRECTION_TX;
ret = of_property_read_string(pdev->dev.of_node, "allwinner,direction",
&direction);
if (!ret && !strncmp(direction, "rx", 2))
dphy->direction = SUN6I_DPHY_DIRECTION_RX;
phy_set_drvdata(dphy->phy, dphy);
phy_provider = devm_of_phy_provider_register(&pdev->dev, of_phy_simple_xlate);
return PTR_ERR_OR_ZERO(phy_provider);
}
static const struct of_device_id sun6i_dphy_of_table[] = {
{ .compatible = "allwinner,sun6i-a31-mipi-dphy" },
{ }
};
MODULE_DEVICE_TABLE(of, sun6i_dphy_of_table);
static struct platform_driver sun6i_dphy_platform_driver = {
.probe = sun6i_dphy_probe,
.driver = {
.name = "sun6i-mipi-dphy",
.of_match_table = sun6i_dphy_of_table,
},
};
module_platform_driver(sun6i_dphy_platform_driver);
MODULE_AUTHOR("Maxime Ripard <maxime.ripard@bootlin>");
MODULE_DESCRIPTION("Allwinner A31 MIPI D-PHY Driver");
MODULE_LICENSE("GPL");