linux/drivers/soc/imx/gpc.c
Lucas Stach e0ea2d11f8 soc: imx: gpc: fix power up sequencing
Currently we wait only until the PGC inverts the isolation setting
before disabling the peripheral clocks. This doesn't ensure that the
reset is properly propagated through the peripheral devices in the
power domain.

Wait until the PGC signals that the power up request is done and
wait a bit for resets to propagate before disabling the clocks.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
2020-03-16 11:39:02 +08:00

555 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2015-2017 Pengutronix, Lucas Stach <kernel@pengutronix.de>
* Copyright 2011-2013 Freescale Semiconductor, Inc.
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#define GPC_CNTR 0x000
#define GPC_PGC_CTRL_OFFS 0x0
#define GPC_PGC_PUPSCR_OFFS 0x4
#define GPC_PGC_PDNSCR_OFFS 0x8
#define GPC_PGC_SW2ISO_SHIFT 0x8
#define GPC_PGC_SW_SHIFT 0x0
#define GPC_PGC_PCI_PDN 0x200
#define GPC_PGC_PCI_SR 0x20c
#define GPC_PGC_GPU_PDN 0x260
#define GPC_PGC_GPU_PUPSCR 0x264
#define GPC_PGC_GPU_PDNSCR 0x268
#define GPC_PGC_GPU_SR 0x26c
#define GPC_PGC_DISP_PDN 0x240
#define GPC_PGC_DISP_SR 0x24c
#define GPU_VPU_PUP_REQ BIT(1)
#define GPU_VPU_PDN_REQ BIT(0)
#define GPC_CLK_MAX 7
#define PGC_DOMAIN_FLAG_NO_PD BIT(0)
struct imx_pm_domain {
struct generic_pm_domain base;
struct regmap *regmap;
struct regulator *supply;
struct clk *clk[GPC_CLK_MAX];
int num_clks;
unsigned int reg_offs;
signed char cntr_pdn_bit;
unsigned int ipg_rate_mhz;
};
static inline struct imx_pm_domain *
to_imx_pm_domain(struct generic_pm_domain *genpd)
{
return container_of(genpd, struct imx_pm_domain, base);
}
static int imx6_pm_domain_power_off(struct generic_pm_domain *genpd)
{
struct imx_pm_domain *pd = to_imx_pm_domain(genpd);
int iso, iso2sw;
u32 val;
/* Read ISO and ISO2SW power down delays */
regmap_read(pd->regmap, pd->reg_offs + GPC_PGC_PDNSCR_OFFS, &val);
iso = val & 0x3f;
iso2sw = (val >> 8) & 0x3f;
/* Gate off domain when powered down */
regmap_update_bits(pd->regmap, pd->reg_offs + GPC_PGC_CTRL_OFFS,
0x1, 0x1);
/* Request GPC to power down domain */
val = BIT(pd->cntr_pdn_bit);
regmap_update_bits(pd->regmap, GPC_CNTR, val, val);
/* Wait ISO + ISO2SW IPG clock cycles */
udelay(DIV_ROUND_UP(iso + iso2sw, pd->ipg_rate_mhz));
if (pd->supply)
regulator_disable(pd->supply);
return 0;
}
static int imx6_pm_domain_power_on(struct generic_pm_domain *genpd)
{
struct imx_pm_domain *pd = to_imx_pm_domain(genpd);
int i, ret;
u32 val, req;
if (pd->supply) {
ret = regulator_enable(pd->supply);
if (ret) {
pr_err("%s: failed to enable regulator: %d\n",
__func__, ret);
return ret;
}
}
/* Enable reset clocks for all devices in the domain */
for (i = 0; i < pd->num_clks; i++)
clk_prepare_enable(pd->clk[i]);
/* Gate off domain when powered down */
regmap_update_bits(pd->regmap, pd->reg_offs + GPC_PGC_CTRL_OFFS,
0x1, 0x1);
/* Request GPC to power up domain */
req = BIT(pd->cntr_pdn_bit + 1);
regmap_update_bits(pd->regmap, GPC_CNTR, req, req);
/* Wait for the PGC to handle the request */
ret = regmap_read_poll_timeout(pd->regmap, GPC_CNTR, val, !(val & req),
1, 50);
if (ret)
pr_err("powerup request on domain %s timed out\n", genpd->name);
/* Wait for reset to propagate through peripherals */
usleep_range(5, 10);
/* Disable reset clocks for all devices in the domain */
for (i = 0; i < pd->num_clks; i++)
clk_disable_unprepare(pd->clk[i]);
return 0;
}
static int imx_pgc_get_clocks(struct device *dev, struct imx_pm_domain *domain)
{
int i, ret;
for (i = 0; ; i++) {
struct clk *clk = of_clk_get(dev->of_node, i);
if (IS_ERR(clk))
break;
if (i >= GPC_CLK_MAX) {
dev_err(dev, "more than %d clocks\n", GPC_CLK_MAX);
ret = -EINVAL;
goto clk_err;
}
domain->clk[i] = clk;
}
domain->num_clks = i;
return 0;
clk_err:
while (i--)
clk_put(domain->clk[i]);
return ret;
}
static void imx_pgc_put_clocks(struct imx_pm_domain *domain)
{
int i;
for (i = domain->num_clks - 1; i >= 0; i--)
clk_put(domain->clk[i]);
}
static int imx_pgc_parse_dt(struct device *dev, struct imx_pm_domain *domain)
{
/* try to get the domain supply regulator */
domain->supply = devm_regulator_get_optional(dev, "power");
if (IS_ERR(domain->supply)) {
if (PTR_ERR(domain->supply) == -ENODEV)
domain->supply = NULL;
else
return PTR_ERR(domain->supply);
}
/* try to get all clocks needed for reset propagation */
return imx_pgc_get_clocks(dev, domain);
}
static int imx_pgc_power_domain_probe(struct platform_device *pdev)
{
struct imx_pm_domain *domain = pdev->dev.platform_data;
struct device *dev = &pdev->dev;
int ret;
/* if this PD is associated with a DT node try to parse it */
if (dev->of_node) {
ret = imx_pgc_parse_dt(dev, domain);
if (ret)
return ret;
}
/* initially power on the domain */
if (domain->base.power_on)
domain->base.power_on(&domain->base);
if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
pm_genpd_init(&domain->base, NULL, false);
ret = of_genpd_add_provider_simple(dev->of_node, &domain->base);
if (ret)
goto genpd_err;
}
device_link_add(dev, dev->parent, DL_FLAG_AUTOREMOVE_CONSUMER);
return 0;
genpd_err:
pm_genpd_remove(&domain->base);
imx_pgc_put_clocks(domain);
return ret;
}
static int imx_pgc_power_domain_remove(struct platform_device *pdev)
{
struct imx_pm_domain *domain = pdev->dev.platform_data;
if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
of_genpd_del_provider(pdev->dev.of_node);
pm_genpd_remove(&domain->base);
imx_pgc_put_clocks(domain);
}
return 0;
}
static const struct platform_device_id imx_pgc_power_domain_id[] = {
{ "imx-pgc-power-domain"},
{ },
};
static struct platform_driver imx_pgc_power_domain_driver = {
.driver = {
.name = "imx-pgc-pd",
},
.probe = imx_pgc_power_domain_probe,
.remove = imx_pgc_power_domain_remove,
.id_table = imx_pgc_power_domain_id,
};
builtin_platform_driver(imx_pgc_power_domain_driver)
#define GPC_PGC_DOMAIN_ARM 0
#define GPC_PGC_DOMAIN_PU 1
#define GPC_PGC_DOMAIN_DISPLAY 2
#define GPC_PGC_DOMAIN_PCI 3
static struct genpd_power_state imx6_pm_domain_pu_state = {
.power_off_latency_ns = 25000,
.power_on_latency_ns = 2000000,
};
static struct imx_pm_domain imx_gpc_domains[] = {
[GPC_PGC_DOMAIN_ARM] = {
.base = {
.name = "ARM",
.flags = GENPD_FLAG_ALWAYS_ON,
},
},
[GPC_PGC_DOMAIN_PU] = {
.base = {
.name = "PU",
.power_off = imx6_pm_domain_power_off,
.power_on = imx6_pm_domain_power_on,
.states = &imx6_pm_domain_pu_state,
.state_count = 1,
},
.reg_offs = 0x260,
.cntr_pdn_bit = 0,
},
[GPC_PGC_DOMAIN_DISPLAY] = {
.base = {
.name = "DISPLAY",
.power_off = imx6_pm_domain_power_off,
.power_on = imx6_pm_domain_power_on,
},
.reg_offs = 0x240,
.cntr_pdn_bit = 4,
},
[GPC_PGC_DOMAIN_PCI] = {
.base = {
.name = "PCI",
.power_off = imx6_pm_domain_power_off,
.power_on = imx6_pm_domain_power_on,
},
.reg_offs = 0x200,
.cntr_pdn_bit = 6,
},
};
struct imx_gpc_dt_data {
int num_domains;
bool err009619_present;
bool err006287_present;
};
static const struct imx_gpc_dt_data imx6q_dt_data = {
.num_domains = 2,
.err009619_present = false,
.err006287_present = false,
};
static const struct imx_gpc_dt_data imx6qp_dt_data = {
.num_domains = 2,
.err009619_present = true,
.err006287_present = false,
};
static const struct imx_gpc_dt_data imx6sl_dt_data = {
.num_domains = 3,
.err009619_present = false,
.err006287_present = true,
};
static const struct imx_gpc_dt_data imx6sx_dt_data = {
.num_domains = 4,
.err009619_present = false,
.err006287_present = false,
};
static const struct of_device_id imx_gpc_dt_ids[] = {
{ .compatible = "fsl,imx6q-gpc", .data = &imx6q_dt_data },
{ .compatible = "fsl,imx6qp-gpc", .data = &imx6qp_dt_data },
{ .compatible = "fsl,imx6sl-gpc", .data = &imx6sl_dt_data },
{ .compatible = "fsl,imx6sx-gpc", .data = &imx6sx_dt_data },
{ }
};
static const struct regmap_range yes_ranges[] = {
regmap_reg_range(GPC_CNTR, GPC_CNTR),
regmap_reg_range(GPC_PGC_PCI_PDN, GPC_PGC_PCI_SR),
regmap_reg_range(GPC_PGC_GPU_PDN, GPC_PGC_GPU_SR),
regmap_reg_range(GPC_PGC_DISP_PDN, GPC_PGC_DISP_SR),
};
static const struct regmap_access_table access_table = {
.yes_ranges = yes_ranges,
.n_yes_ranges = ARRAY_SIZE(yes_ranges),
};
static const struct regmap_config imx_gpc_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
.rd_table = &access_table,
.wr_table = &access_table,
.max_register = 0x2ac,
.fast_io = true,
};
static struct generic_pm_domain *imx_gpc_onecell_domains[] = {
&imx_gpc_domains[GPC_PGC_DOMAIN_ARM].base,
&imx_gpc_domains[GPC_PGC_DOMAIN_PU].base,
};
static struct genpd_onecell_data imx_gpc_onecell_data = {
.domains = imx_gpc_onecell_domains,
.num_domains = 2,
};
static int imx_gpc_old_dt_init(struct device *dev, struct regmap *regmap,
unsigned int num_domains)
{
struct imx_pm_domain *domain;
int i, ret;
for (i = 0; i < num_domains; i++) {
domain = &imx_gpc_domains[i];
domain->regmap = regmap;
domain->ipg_rate_mhz = 66;
if (i == 1) {
domain->supply = devm_regulator_get(dev, "pu");
if (IS_ERR(domain->supply))
return PTR_ERR(domain->supply);
ret = imx_pgc_get_clocks(dev, domain);
if (ret)
goto clk_err;
domain->base.power_on(&domain->base);
}
}
for (i = 0; i < num_domains; i++)
pm_genpd_init(&imx_gpc_domains[i].base, NULL, false);
if (IS_ENABLED(CONFIG_PM_GENERIC_DOMAINS)) {
ret = of_genpd_add_provider_onecell(dev->of_node,
&imx_gpc_onecell_data);
if (ret)
goto genpd_err;
}
return 0;
genpd_err:
for (i = 0; i < num_domains; i++)
pm_genpd_remove(&imx_gpc_domains[i].base);
imx_pgc_put_clocks(&imx_gpc_domains[GPC_PGC_DOMAIN_PU]);
clk_err:
return ret;
}
static int imx_gpc_probe(struct platform_device *pdev)
{
const struct of_device_id *of_id =
of_match_device(imx_gpc_dt_ids, &pdev->dev);
const struct imx_gpc_dt_data *of_id_data = of_id->data;
struct device_node *pgc_node;
struct regmap *regmap;
void __iomem *base;
int ret;
pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc");
/* bail out if DT too old and doesn't provide the necessary info */
if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells") &&
!pgc_node)
return 0;
base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(base))
return PTR_ERR(base);
regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
&imx_gpc_regmap_config);
if (IS_ERR(regmap)) {
ret = PTR_ERR(regmap);
dev_err(&pdev->dev, "failed to init regmap: %d\n",
ret);
return ret;
}
/*
* Disable PU power down by runtime PM if ERR009619 is present.
*
* The PRE clock will be paused for several cycles when turning on the
* PU domain LDO from power down state. If PRE is in use at that time,
* the IPU/PRG cannot get the correct display data from the PRE.
*
* This is not a concern when the whole system enters suspend state, so
* it's safe to power down PU in this case.
*/
if (of_id_data->err009619_present)
imx_gpc_domains[GPC_PGC_DOMAIN_PU].base.flags |=
GENPD_FLAG_RPM_ALWAYS_ON;
/* Keep DISP always on if ERR006287 is present */
if (of_id_data->err006287_present)
imx_gpc_domains[GPC_PGC_DOMAIN_DISPLAY].base.flags |=
GENPD_FLAG_ALWAYS_ON;
if (!pgc_node) {
ret = imx_gpc_old_dt_init(&pdev->dev, regmap,
of_id_data->num_domains);
if (ret)
return ret;
} else {
struct imx_pm_domain *domain;
struct platform_device *pd_pdev;
struct device_node *np;
struct clk *ipg_clk;
unsigned int ipg_rate_mhz;
int domain_index;
ipg_clk = devm_clk_get(&pdev->dev, "ipg");
if (IS_ERR(ipg_clk))
return PTR_ERR(ipg_clk);
ipg_rate_mhz = clk_get_rate(ipg_clk) / 1000000;
for_each_child_of_node(pgc_node, np) {
ret = of_property_read_u32(np, "reg", &domain_index);
if (ret) {
of_node_put(np);
return ret;
}
if (domain_index >= of_id_data->num_domains)
continue;
pd_pdev = platform_device_alloc("imx-pgc-power-domain",
domain_index);
if (!pd_pdev) {
of_node_put(np);
return -ENOMEM;
}
ret = platform_device_add_data(pd_pdev,
&imx_gpc_domains[domain_index],
sizeof(imx_gpc_domains[domain_index]));
if (ret) {
platform_device_put(pd_pdev);
of_node_put(np);
return ret;
}
domain = pd_pdev->dev.platform_data;
domain->regmap = regmap;
domain->ipg_rate_mhz = ipg_rate_mhz;
pd_pdev->dev.parent = &pdev->dev;
pd_pdev->dev.of_node = np;
ret = platform_device_add(pd_pdev);
if (ret) {
platform_device_put(pd_pdev);
of_node_put(np);
return ret;
}
}
}
return 0;
}
static int imx_gpc_remove(struct platform_device *pdev)
{
struct device_node *pgc_node;
int ret;
pgc_node = of_get_child_by_name(pdev->dev.of_node, "pgc");
/* bail out if DT too old and doesn't provide the necessary info */
if (!of_property_read_bool(pdev->dev.of_node, "#power-domain-cells") &&
!pgc_node)
return 0;
/*
* If the old DT binding is used the toplevel driver needs to
* de-register the power domains
*/
if (!pgc_node) {
of_genpd_del_provider(pdev->dev.of_node);
ret = pm_genpd_remove(&imx_gpc_domains[GPC_PGC_DOMAIN_PU].base);
if (ret)
return ret;
imx_pgc_put_clocks(&imx_gpc_domains[GPC_PGC_DOMAIN_PU]);
ret = pm_genpd_remove(&imx_gpc_domains[GPC_PGC_DOMAIN_ARM].base);
if (ret)
return ret;
}
return 0;
}
static struct platform_driver imx_gpc_driver = {
.driver = {
.name = "imx-gpc",
.of_match_table = imx_gpc_dt_ids,
},
.probe = imx_gpc_probe,
.remove = imx_gpc_remove,
};
builtin_platform_driver(imx_gpc_driver)