linux/drivers/phy/cadence/cdns-dphy.c

392 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright: 2017-2018 Cadence Design Systems, Inc.
*/
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
#include <linux/phy/phy.h>
#include <linux/phy/phy-mipi-dphy.h>
#define REG_WAKEUP_TIME_NS 800
#define DPHY_PLL_RATE_HZ 108000000
/* DPHY registers */
#define DPHY_PMA_CMN(reg) (reg)
#define DPHY_PMA_LCLK(reg) (0x100 + (reg))
#define DPHY_PMA_LDATA(lane, reg) (0x200 + ((lane) * 0x100) + (reg))
#define DPHY_PMA_RCLK(reg) (0x600 + (reg))
#define DPHY_PMA_RDATA(lane, reg) (0x700 + ((lane) * 0x100) + (reg))
#define DPHY_PCS(reg) (0xb00 + (reg))
#define DPHY_CMN_SSM DPHY_PMA_CMN(0x20)
#define DPHY_CMN_SSM_EN BIT(0)
#define DPHY_CMN_TX_MODE_EN BIT(9)
#define DPHY_CMN_PWM DPHY_PMA_CMN(0x40)
#define DPHY_CMN_PWM_DIV(x) ((x) << 20)
#define DPHY_CMN_PWM_LOW(x) ((x) << 10)
#define DPHY_CMN_PWM_HIGH(x) (x)
#define DPHY_CMN_FBDIV DPHY_PMA_CMN(0x4c)
#define DPHY_CMN_FBDIV_VAL(low, high) (((high) << 11) | ((low) << 22))
#define DPHY_CMN_FBDIV_FROM_REG (BIT(10) | BIT(21))
#define DPHY_CMN_OPIPDIV DPHY_PMA_CMN(0x50)
#define DPHY_CMN_IPDIV_FROM_REG BIT(0)
#define DPHY_CMN_IPDIV(x) ((x) << 1)
#define DPHY_CMN_OPDIV_FROM_REG BIT(6)
#define DPHY_CMN_OPDIV(x) ((x) << 7)
#define DPHY_PSM_CFG DPHY_PCS(0x4)
#define DPHY_PSM_CFG_FROM_REG BIT(0)
#define DPHY_PSM_CLK_DIV(x) ((x) << 1)
#define DSI_HBP_FRAME_OVERHEAD 12
#define DSI_HSA_FRAME_OVERHEAD 14
#define DSI_HFP_FRAME_OVERHEAD 6
#define DSI_HSS_VSS_VSE_FRAME_OVERHEAD 4
#define DSI_BLANKING_FRAME_OVERHEAD 6
#define DSI_NULL_FRAME_OVERHEAD 6
#define DSI_EOT_PKT_SIZE 4
struct cdns_dphy_cfg {
u8 pll_ipdiv;
u8 pll_opdiv;
u16 pll_fbdiv;
unsigned int nlanes;
};
enum cdns_dphy_clk_lane_cfg {
DPHY_CLK_CFG_LEFT_DRIVES_ALL = 0,
DPHY_CLK_CFG_LEFT_DRIVES_RIGHT = 1,
DPHY_CLK_CFG_LEFT_DRIVES_LEFT = 2,
DPHY_CLK_CFG_RIGHT_DRIVES_ALL = 3,
};
struct cdns_dphy;
struct cdns_dphy_ops {
int (*probe)(struct cdns_dphy *dphy);
void (*remove)(struct cdns_dphy *dphy);
void (*set_psm_div)(struct cdns_dphy *dphy, u8 div);
void (*set_clk_lane_cfg)(struct cdns_dphy *dphy,
enum cdns_dphy_clk_lane_cfg cfg);
void (*set_pll_cfg)(struct cdns_dphy *dphy,
const struct cdns_dphy_cfg *cfg);
unsigned long (*get_wakeup_time_ns)(struct cdns_dphy *dphy);
};
struct cdns_dphy {
struct cdns_dphy_cfg cfg;
void __iomem *regs;
struct clk *psm_clk;
struct clk *pll_ref_clk;
const struct cdns_dphy_ops *ops;
struct phy *phy;
};
static int cdns_dsi_get_dphy_pll_cfg(struct cdns_dphy *dphy,
struct cdns_dphy_cfg *cfg,
struct phy_configure_opts_mipi_dphy *opts,
unsigned int *dsi_hfp_ext)
{
unsigned long pll_ref_hz = clk_get_rate(dphy->pll_ref_clk);
u64 dlane_bps;
memset(cfg, 0, sizeof(*cfg));
if (pll_ref_hz < 9600000 || pll_ref_hz >= 150000000)
return -EINVAL;
else if (pll_ref_hz < 19200000)
cfg->pll_ipdiv = 1;
else if (pll_ref_hz < 38400000)
cfg->pll_ipdiv = 2;
else if (pll_ref_hz < 76800000)
cfg->pll_ipdiv = 4;
else
cfg->pll_ipdiv = 8;
dlane_bps = opts->hs_clk_rate;
if (dlane_bps > 2500000000UL || dlane_bps < 160000000UL)
return -EINVAL;
else if (dlane_bps >= 1250000000)
cfg->pll_opdiv = 1;
else if (dlane_bps >= 630000000)
cfg->pll_opdiv = 2;
else if (dlane_bps >= 320000000)
cfg->pll_opdiv = 4;
else if (dlane_bps >= 160000000)
cfg->pll_opdiv = 8;
cfg->pll_fbdiv = DIV_ROUND_UP_ULL(dlane_bps * 2 * cfg->pll_opdiv *
cfg->pll_ipdiv,
pll_ref_hz);
return 0;
}
static int cdns_dphy_setup_psm(struct cdns_dphy *dphy)
{
unsigned long psm_clk_hz = clk_get_rate(dphy->psm_clk);
unsigned long psm_div;
if (!psm_clk_hz || psm_clk_hz > 100000000)
return -EINVAL;
psm_div = DIV_ROUND_CLOSEST(psm_clk_hz, 1000000);
if (dphy->ops->set_psm_div)
dphy->ops->set_psm_div(dphy, psm_div);
return 0;
}
static void cdns_dphy_set_clk_lane_cfg(struct cdns_dphy *dphy,
enum cdns_dphy_clk_lane_cfg cfg)
{
if (dphy->ops->set_clk_lane_cfg)
dphy->ops->set_clk_lane_cfg(dphy, cfg);
}
static void cdns_dphy_set_pll_cfg(struct cdns_dphy *dphy,
const struct cdns_dphy_cfg *cfg)
{
if (dphy->ops->set_pll_cfg)
dphy->ops->set_pll_cfg(dphy, cfg);
}
static unsigned long cdns_dphy_get_wakeup_time_ns(struct cdns_dphy *dphy)
{
return dphy->ops->get_wakeup_time_ns(dphy);
}
static unsigned long cdns_dphy_ref_get_wakeup_time_ns(struct cdns_dphy *dphy)
{
/* Default wakeup time is 800 ns (in a simulated environment). */
return 800;
}
static void cdns_dphy_ref_set_pll_cfg(struct cdns_dphy *dphy,
const struct cdns_dphy_cfg *cfg)
{
u32 fbdiv_low, fbdiv_high;
fbdiv_low = (cfg->pll_fbdiv / 4) - 2;
fbdiv_high = cfg->pll_fbdiv - fbdiv_low - 2;
writel(DPHY_CMN_IPDIV_FROM_REG | DPHY_CMN_OPDIV_FROM_REG |
DPHY_CMN_IPDIV(cfg->pll_ipdiv) |
DPHY_CMN_OPDIV(cfg->pll_opdiv),
dphy->regs + DPHY_CMN_OPIPDIV);
writel(DPHY_CMN_FBDIV_FROM_REG |
DPHY_CMN_FBDIV_VAL(fbdiv_low, fbdiv_high),
dphy->regs + DPHY_CMN_FBDIV);
writel(DPHY_CMN_PWM_HIGH(6) | DPHY_CMN_PWM_LOW(0x101) |
DPHY_CMN_PWM_DIV(0x8),
dphy->regs + DPHY_CMN_PWM);
}
static void cdns_dphy_ref_set_psm_div(struct cdns_dphy *dphy, u8 div)
{
writel(DPHY_PSM_CFG_FROM_REG | DPHY_PSM_CLK_DIV(div),
dphy->regs + DPHY_PSM_CFG);
}
/*
* This is the reference implementation of DPHY hooks. Specific integration of
* this IP may have to re-implement some of them depending on how they decided
* to wire things in the SoC.
*/
static const struct cdns_dphy_ops ref_dphy_ops = {
.get_wakeup_time_ns = cdns_dphy_ref_get_wakeup_time_ns,
.set_pll_cfg = cdns_dphy_ref_set_pll_cfg,
.set_psm_div = cdns_dphy_ref_set_psm_div,
};
static int cdns_dphy_config_from_opts(struct phy *phy,
struct phy_configure_opts_mipi_dphy *opts,
struct cdns_dphy_cfg *cfg)
{
struct cdns_dphy *dphy = phy_get_drvdata(phy);
unsigned int dsi_hfp_ext = 0;
int ret;
ret = phy_mipi_dphy_config_validate(opts);
if (ret)
return ret;
ret = cdns_dsi_get_dphy_pll_cfg(dphy, cfg,
opts, &dsi_hfp_ext);
if (ret)
return ret;
opts->wakeup = cdns_dphy_get_wakeup_time_ns(dphy) / 1000;
return 0;
}
static int cdns_dphy_validate(struct phy *phy, enum phy_mode mode, int submode,
union phy_configure_opts *opts)
{
struct cdns_dphy_cfg cfg = { 0 };
if (mode != PHY_MODE_MIPI_DPHY)
return -EINVAL;
return cdns_dphy_config_from_opts(phy, &opts->mipi_dphy, &cfg);
}
static int cdns_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
{
struct cdns_dphy *dphy = phy_get_drvdata(phy);
struct cdns_dphy_cfg cfg = { 0 };
int ret;
ret = cdns_dphy_config_from_opts(phy, &opts->mipi_dphy, &cfg);
if (ret)
return ret;
/*
* Configure the internal PSM clk divider so that the DPHY has a
* 1MHz clk (or something close).
*/
ret = cdns_dphy_setup_psm(dphy);
if (ret)
return ret;
/*
* Configure attach clk lanes to data lanes: the DPHY has 2 clk lanes
* and 8 data lanes, each clk lane can be attache different set of
* data lanes. The 2 groups are named 'left' and 'right', so here we
* just say that we want the 'left' clk lane to drive the 'left' data
* lanes.
*/
cdns_dphy_set_clk_lane_cfg(dphy, DPHY_CLK_CFG_LEFT_DRIVES_LEFT);
/*
* Configure the DPHY PLL that will be used to generate the TX byte
* clk.
*/
cdns_dphy_set_pll_cfg(dphy, &cfg);
return 0;
}
static int cdns_dphy_power_on(struct phy *phy)
{
struct cdns_dphy *dphy = phy_get_drvdata(phy);
clk_prepare_enable(dphy->psm_clk);
clk_prepare_enable(dphy->pll_ref_clk);
/* Start TX state machine. */
writel(DPHY_CMN_SSM_EN | DPHY_CMN_TX_MODE_EN,
dphy->regs + DPHY_CMN_SSM);
return 0;
}
static int cdns_dphy_power_off(struct phy *phy)
{
struct cdns_dphy *dphy = phy_get_drvdata(phy);
clk_disable_unprepare(dphy->pll_ref_clk);
clk_disable_unprepare(dphy->psm_clk);
return 0;
}
static const struct phy_ops cdns_dphy_ops = {
.configure = cdns_dphy_configure,
.validate = cdns_dphy_validate,
.power_on = cdns_dphy_power_on,
.power_off = cdns_dphy_power_off,
};
static int cdns_dphy_probe(struct platform_device *pdev)
{
struct phy_provider *phy_provider;
struct cdns_dphy *dphy;
struct resource *res;
int ret;
dphy = devm_kzalloc(&pdev->dev, sizeof(*dphy), GFP_KERNEL);
if (!dphy)
return -ENOMEM;
dev_set_drvdata(&pdev->dev, dphy);
dphy->ops = of_device_get_match_data(&pdev->dev);
if (!dphy->ops)
return -EINVAL;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
dphy->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(dphy->regs))
return PTR_ERR(dphy->regs);
dphy->psm_clk = devm_clk_get(&pdev->dev, "psm");
if (IS_ERR(dphy->psm_clk))
return PTR_ERR(dphy->psm_clk);
dphy->pll_ref_clk = devm_clk_get(&pdev->dev, "pll_ref");
if (IS_ERR(dphy->pll_ref_clk))
return PTR_ERR(dphy->pll_ref_clk);
if (dphy->ops->probe) {
ret = dphy->ops->probe(dphy);
if (ret)
return ret;
}
dphy->phy = devm_phy_create(&pdev->dev, NULL, &cdns_dphy_ops);
if (IS_ERR(dphy->phy)) {
dev_err(&pdev->dev, "failed to create PHY\n");
if (dphy->ops->remove)
dphy->ops->remove(dphy);
return PTR_ERR(dphy->phy);
}
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 int cdns_dphy_remove(struct platform_device *pdev)
{
struct cdns_dphy *dphy = dev_get_drvdata(&pdev->dev);
if (dphy->ops->remove)
dphy->ops->remove(dphy);
return 0;
}
static const struct of_device_id cdns_dphy_of_match[] = {
{ .compatible = "cdns,dphy", .data = &ref_dphy_ops },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, cdns_dphy_of_match);
static struct platform_driver cdns_dphy_platform_driver = {
.probe = cdns_dphy_probe,
.remove = cdns_dphy_remove,
.driver = {
.name = "cdns-mipi-dphy",
.of_match_table = cdns_dphy_of_match,
},
};
module_platform_driver(cdns_dphy_platform_driver);
MODULE_AUTHOR("Maxime Ripard <maxime.ripard@bootlin.com>");
MODULE_DESCRIPTION("Cadence MIPI D-PHY Driver");
MODULE_LICENSE("GPL");