linux/drivers/soc/rockchip/grf.c
Douglas Anderson bbdc00a7de soc: rockchip: Set the proper PWM for rk3288
The rk3288 SoC has two PWM implementations available, the "old"
implementation and the "new" one.  You can switch between the two of
them by flipping a bit in the grf.

The "old" implementation is the default at chip power up but isn't the
one that's officially supposed to be used.  ...and, in fact, the
driver that gets selected in Linux using the rk3288 device tree only
supports the "new" implementation.

Long ago I tried to get a switch to the right IP block landed in the
PWM driver (search for "rk3288: Switch to use the proper PWM IP") but
that got rejected.  In the mean time the grf has grown a full-fledged
driver that already sets other random bits like this.  That means we
can now get the fix landed.

For those wondering how things could have possibly worked for the last
4.5 years, folks have mostly been relying on the bootloader to set
this bit.  ...but occasionally folks have pointed back to my old patch
series [1] in downstream kernels.

[1] https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1391597.html

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
2019-04-11 13:40:32 +02:00

179 lines
4.7 KiB
C

/*
* Rockchip Generic Register Files setup
*
* Copyright (c) 2016 Heiko Stuebner <heiko@sntech.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/err.h>
#include <linux/mfd/syscon.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#define HIWORD_UPDATE(val, mask, shift) \
((val) << (shift) | (mask) << ((shift) + 16))
struct rockchip_grf_value {
const char *desc;
u32 reg;
u32 val;
};
struct rockchip_grf_info {
const struct rockchip_grf_value *values;
int num_values;
};
#define RK3036_GRF_SOC_CON0 0x140
static const struct rockchip_grf_value rk3036_defaults[] __initconst = {
/*
* Disable auto jtag/sdmmc switching that causes issues with the
* clock-framework and the mmc controllers making them unreliable.
*/
{ "jtag switching", RK3036_GRF_SOC_CON0, HIWORD_UPDATE(0, 1, 11) },
};
static const struct rockchip_grf_info rk3036_grf __initconst = {
.values = rk3036_defaults,
.num_values = ARRAY_SIZE(rk3036_defaults),
};
#define RK3128_GRF_SOC_CON0 0x140
static const struct rockchip_grf_value rk3128_defaults[] __initconst = {
{ "jtag switching", RK3128_GRF_SOC_CON0, HIWORD_UPDATE(0, 1, 8) },
};
static const struct rockchip_grf_info rk3128_grf __initconst = {
.values = rk3128_defaults,
.num_values = ARRAY_SIZE(rk3128_defaults),
};
#define RK3228_GRF_SOC_CON6 0x418
static const struct rockchip_grf_value rk3228_defaults[] __initconst = {
{ "jtag switching", RK3228_GRF_SOC_CON6, HIWORD_UPDATE(0, 1, 8) },
};
static const struct rockchip_grf_info rk3228_grf __initconst = {
.values = rk3228_defaults,
.num_values = ARRAY_SIZE(rk3228_defaults),
};
#define RK3288_GRF_SOC_CON0 0x244
#define RK3288_GRF_SOC_CON2 0x24c
static const struct rockchip_grf_value rk3288_defaults[] __initconst = {
{ "jtag switching", RK3288_GRF_SOC_CON0, HIWORD_UPDATE(0, 1, 12) },
{ "pwm select", RK3288_GRF_SOC_CON2, HIWORD_UPDATE(1, 1, 0) },
};
static const struct rockchip_grf_info rk3288_grf __initconst = {
.values = rk3288_defaults,
.num_values = ARRAY_SIZE(rk3288_defaults),
};
#define RK3328_GRF_SOC_CON4 0x410
static const struct rockchip_grf_value rk3328_defaults[] __initconst = {
{ "jtag switching", RK3328_GRF_SOC_CON4, HIWORD_UPDATE(0, 1, 12) },
};
static const struct rockchip_grf_info rk3328_grf __initconst = {
.values = rk3328_defaults,
.num_values = ARRAY_SIZE(rk3328_defaults),
};
#define RK3368_GRF_SOC_CON15 0x43c
static const struct rockchip_grf_value rk3368_defaults[] __initconst = {
{ "jtag switching", RK3368_GRF_SOC_CON15, HIWORD_UPDATE(0, 1, 13) },
};
static const struct rockchip_grf_info rk3368_grf __initconst = {
.values = rk3368_defaults,
.num_values = ARRAY_SIZE(rk3368_defaults),
};
#define RK3399_GRF_SOC_CON7 0xe21c
static const struct rockchip_grf_value rk3399_defaults[] __initconst = {
{ "jtag switching", RK3399_GRF_SOC_CON7, HIWORD_UPDATE(0, 1, 12) },
};
static const struct rockchip_grf_info rk3399_grf __initconst = {
.values = rk3399_defaults,
.num_values = ARRAY_SIZE(rk3399_defaults),
};
static const struct of_device_id rockchip_grf_dt_match[] __initconst = {
{
.compatible = "rockchip,rk3036-grf",
.data = (void *)&rk3036_grf,
}, {
.compatible = "rockchip,rk3128-grf",
.data = (void *)&rk3128_grf,
}, {
.compatible = "rockchip,rk3228-grf",
.data = (void *)&rk3228_grf,
}, {
.compatible = "rockchip,rk3288-grf",
.data = (void *)&rk3288_grf,
}, {
.compatible = "rockchip,rk3328-grf",
.data = (void *)&rk3328_grf,
}, {
.compatible = "rockchip,rk3368-grf",
.data = (void *)&rk3368_grf,
}, {
.compatible = "rockchip,rk3399-grf",
.data = (void *)&rk3399_grf,
},
{ /* sentinel */ },
};
static int __init rockchip_grf_init(void)
{
const struct rockchip_grf_info *grf_info;
const struct of_device_id *match;
struct device_node *np;
struct regmap *grf;
int ret, i;
np = of_find_matching_node_and_match(NULL, rockchip_grf_dt_match,
&match);
if (!np)
return -ENODEV;
if (!match || !match->data) {
pr_err("%s: missing grf data\n", __func__);
return -EINVAL;
}
grf_info = match->data;
grf = syscon_node_to_regmap(np);
if (IS_ERR(grf)) {
pr_err("%s: could not get grf syscon\n", __func__);
return PTR_ERR(grf);
}
for (i = 0; i < grf_info->num_values; i++) {
const struct rockchip_grf_value *val = &grf_info->values[i];
pr_debug("%s: adjusting %s in %#6x to %#10x\n", __func__,
val->desc, val->reg, val->val);
ret = regmap_write(grf, val->reg, val->val);
if (ret < 0)
pr_err("%s: write to %#6x failed with %d\n",
__func__, val->reg, ret);
}
return 0;
}
postcore_initcall(rockchip_grf_init);