linux/drivers/soc/ti/omap_prm.c
Wei Yongjun c6b69bf143 soc: ti: omap-prm: fix return value check in omap_prm_probe()
In case of error, the function devm_ioremap_resource() returns ERR_PTR()
and never returns NULL. The NULL test in the return value check should
be replaced with IS_ERR().

Fixes: 3e99cb214f ("soc: ti: add initial PRM driver with reset control support")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
2019-10-29 09:57:56 -07:00

392 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* OMAP2+ PRM driver
*
* Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
* Tero Kristo <t-kristo@ti.com>
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>
#include <linux/delay.h>
#include <linux/platform_data/ti-prm.h>
struct omap_rst_map {
s8 rst;
s8 st;
};
struct omap_prm_data {
u32 base;
const char *name;
const char *clkdm_name;
u16 rstctrl;
u16 rstst;
const struct omap_rst_map *rstmap;
u8 flags;
};
struct omap_prm {
const struct omap_prm_data *data;
void __iomem *base;
};
struct omap_reset_data {
struct reset_controller_dev rcdev;
struct omap_prm *prm;
u32 mask;
spinlock_t lock;
struct clockdomain *clkdm;
struct device *dev;
};
#define to_omap_reset_data(p) container_of((p), struct omap_reset_data, rcdev)
#define OMAP_MAX_RESETS 8
#define OMAP_RESET_MAX_WAIT 10000
#define OMAP_PRM_HAS_RSTCTRL BIT(0)
#define OMAP_PRM_HAS_RSTST BIT(1)
#define OMAP_PRM_HAS_NO_CLKDM BIT(2)
#define OMAP_PRM_HAS_RESETS (OMAP_PRM_HAS_RSTCTRL | OMAP_PRM_HAS_RSTST)
static const struct omap_rst_map rst_map_0[] = {
{ .rst = 0, .st = 0 },
{ .rst = -1 },
};
static const struct omap_rst_map rst_map_01[] = {
{ .rst = 0, .st = 0 },
{ .rst = 1, .st = 1 },
{ .rst = -1 },
};
static const struct omap_rst_map rst_map_012[] = {
{ .rst = 0, .st = 0 },
{ .rst = 1, .st = 1 },
{ .rst = 2, .st = 2 },
{ .rst = -1 },
};
static const struct omap_prm_data omap4_prm_data[] = {
{ .name = "tesla", .base = 0x4a306400, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_01 },
{ .name = "core", .base = 0x4a306700, .rstctrl = 0x210, .rstst = 0x214, .clkdm_name = "ducati", .rstmap = rst_map_012 },
{ .name = "ivahd", .base = 0x4a306f00, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_012 },
{ .name = "device", .base = 0x4a307b00, .rstctrl = 0x0, .rstst = 0x4, .rstmap = rst_map_01, .flags = OMAP_PRM_HAS_RSTCTRL | OMAP_PRM_HAS_NO_CLKDM },
{ },
};
static const struct omap_prm_data omap5_prm_data[] = {
{ .name = "dsp", .base = 0x4ae06400, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_01 },
{ .name = "core", .base = 0x4ae06700, .rstctrl = 0x210, .rstst = 0x214, .clkdm_name = "ipu", .rstmap = rst_map_012 },
{ .name = "iva", .base = 0x4ae07200, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_012 },
{ .name = "device", .base = 0x4ae07c00, .rstctrl = 0x0, .rstst = 0x4, .rstmap = rst_map_01, .flags = OMAP_PRM_HAS_RSTCTRL | OMAP_PRM_HAS_NO_CLKDM },
{ },
};
static const struct omap_prm_data dra7_prm_data[] = {
{ .name = "dsp1", .base = 0x4ae06400, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_01 },
{ .name = "ipu", .base = 0x4ae06500, .rstctrl = 0x10, .rstst = 0x14, .clkdm_name = "ipu1", .rstmap = rst_map_012 },
{ .name = "core", .base = 0x4ae06700, .rstctrl = 0x210, .rstst = 0x214, .clkdm_name = "ipu2", .rstmap = rst_map_012 },
{ .name = "iva", .base = 0x4ae06f00, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_012 },
{ .name = "dsp2", .base = 0x4ae07b00, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_01 },
{ .name = "eve1", .base = 0x4ae07b40, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_01 },
{ .name = "eve2", .base = 0x4ae07b80, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_01 },
{ .name = "eve3", .base = 0x4ae07bc0, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_01 },
{ .name = "eve4", .base = 0x4ae07c00, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_01 },
{ },
};
static const struct omap_rst_map am3_per_rst_map[] = {
{ .rst = 1 },
{ .rst = -1 },
};
static const struct omap_rst_map am3_wkup_rst_map[] = {
{ .rst = 3, .st = 5 },
{ .rst = -1 },
};
static const struct omap_prm_data am3_prm_data[] = {
{ .name = "per", .base = 0x44e00c00, .rstctrl = 0x0, .rstmap = am3_per_rst_map, .flags = OMAP_PRM_HAS_RSTCTRL, .clkdm_name = "pruss_ocp" },
{ .name = "wkup", .base = 0x44e00d00, .rstctrl = 0x0, .rstst = 0xc, .rstmap = am3_wkup_rst_map, .flags = OMAP_PRM_HAS_RSTCTRL | OMAP_PRM_HAS_NO_CLKDM },
{ .name = "device", .base = 0x44e00f00, .rstctrl = 0x0, .rstst = 0x8, .rstmap = rst_map_01, .flags = OMAP_PRM_HAS_RSTCTRL | OMAP_PRM_HAS_NO_CLKDM },
{ .name = "gfx", .base = 0x44e01100, .rstctrl = 0x4, .rstst = 0x14, .rstmap = rst_map_0, .clkdm_name = "gfx_l3" },
{ },
};
static const struct omap_rst_map am4_per_rst_map[] = {
{ .rst = 1, .st = 0 },
{ .rst = -1 },
};
static const struct omap_rst_map am4_device_rst_map[] = {
{ .rst = 0, .st = 1 },
{ .rst = 1, .st = 0 },
{ .rst = -1 },
};
static const struct omap_prm_data am4_prm_data[] = {
{ .name = "gfx", .base = 0x44df0400, .rstctrl = 0x10, .rstst = 0x14, .rstmap = rst_map_0, .clkdm_name = "gfx_l3" },
{ .name = "per", .base = 0x44df0800, .rstctrl = 0x10, .rstst = 0x14, .rstmap = am4_per_rst_map, .clkdm_name = "pruss_ocp" },
{ .name = "wkup", .base = 0x44df2000, .rstctrl = 0x10, .rstst = 0x14, .rstmap = am3_wkup_rst_map, .flags = OMAP_PRM_HAS_NO_CLKDM },
{ .name = "device", .base = 0x44df4000, .rstctrl = 0x0, .rstst = 0x4, .rstmap = am4_device_rst_map, .flags = OMAP_PRM_HAS_RSTCTRL | OMAP_PRM_HAS_NO_CLKDM },
{ },
};
static const struct of_device_id omap_prm_id_table[] = {
{ .compatible = "ti,omap4-prm-inst", .data = omap4_prm_data },
{ .compatible = "ti,omap5-prm-inst", .data = omap5_prm_data },
{ .compatible = "ti,dra7-prm-inst", .data = dra7_prm_data },
{ .compatible = "ti,am3-prm-inst", .data = am3_prm_data },
{ .compatible = "ti,am4-prm-inst", .data = am4_prm_data },
{ },
};
static bool _is_valid_reset(struct omap_reset_data *reset, unsigned long id)
{
if (reset->mask & BIT(id))
return true;
return false;
}
static int omap_reset_get_st_bit(struct omap_reset_data *reset,
unsigned long id)
{
const struct omap_rst_map *map = reset->prm->data->rstmap;
while (map->rst >= 0) {
if (map->rst == id)
return map->st;
map++;
}
return id;
}
static int omap_reset_status(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct omap_reset_data *reset = to_omap_reset_data(rcdev);
u32 v;
int st_bit = omap_reset_get_st_bit(reset, id);
bool has_rstst = reset->prm->data->rstst ||
(reset->prm->data->flags & OMAP_PRM_HAS_RSTST);
/* Check if we have rstst */
if (!has_rstst)
return -ENOTSUPP;
/* Check if hw reset line is asserted */
v = readl_relaxed(reset->prm->base + reset->prm->data->rstctrl);
if (v & BIT(id))
return 1;
/*
* Check reset status, high value means reset sequence has been
* completed successfully so we can return 0 here (reset deasserted)
*/
v = readl_relaxed(reset->prm->base + reset->prm->data->rstst);
v >>= st_bit;
v &= 1;
return !v;
}
static int omap_reset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct omap_reset_data *reset = to_omap_reset_data(rcdev);
u32 v;
unsigned long flags;
/* assert the reset control line */
spin_lock_irqsave(&reset->lock, flags);
v = readl_relaxed(reset->prm->base + reset->prm->data->rstctrl);
v |= 1 << id;
writel_relaxed(v, reset->prm->base + reset->prm->data->rstctrl);
spin_unlock_irqrestore(&reset->lock, flags);
return 0;
}
static int omap_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct omap_reset_data *reset = to_omap_reset_data(rcdev);
u32 v;
int st_bit;
bool has_rstst;
unsigned long flags;
struct ti_prm_platform_data *pdata = dev_get_platdata(reset->dev);
int ret = 0;
has_rstst = reset->prm->data->rstst ||
(reset->prm->data->flags & OMAP_PRM_HAS_RSTST);
if (has_rstst) {
st_bit = omap_reset_get_st_bit(reset, id);
/* Clear the reset status by writing 1 to the status bit */
v = 1 << st_bit;
writel_relaxed(v, reset->prm->base + reset->prm->data->rstst);
}
if (reset->clkdm)
pdata->clkdm_deny_idle(reset->clkdm);
/* de-assert the reset control line */
spin_lock_irqsave(&reset->lock, flags);
v = readl_relaxed(reset->prm->base + reset->prm->data->rstctrl);
v &= ~(1 << id);
writel_relaxed(v, reset->prm->base + reset->prm->data->rstctrl);
spin_unlock_irqrestore(&reset->lock, flags);
if (!has_rstst)
goto exit;
/* wait for the status to be set */
ret = readl_relaxed_poll_timeout(reset->prm->base +
reset->prm->data->rstst,
v, v & BIT(st_bit), 1,
OMAP_RESET_MAX_WAIT);
if (ret)
pr_err("%s: timedout waiting for %s:%lu\n", __func__,
reset->prm->data->name, id);
exit:
if (reset->clkdm)
pdata->clkdm_allow_idle(reset->clkdm);
return ret;
}
static const struct reset_control_ops omap_reset_ops = {
.assert = omap_reset_assert,
.deassert = omap_reset_deassert,
.status = omap_reset_status,
};
static int omap_prm_reset_xlate(struct reset_controller_dev *rcdev,
const struct of_phandle_args *reset_spec)
{
struct omap_reset_data *reset = to_omap_reset_data(rcdev);
if (!_is_valid_reset(reset, reset_spec->args[0]))
return -EINVAL;
return reset_spec->args[0];
}
static int omap_prm_reset_init(struct platform_device *pdev,
struct omap_prm *prm)
{
struct omap_reset_data *reset;
const struct omap_rst_map *map;
struct ti_prm_platform_data *pdata = dev_get_platdata(&pdev->dev);
char buf[32];
/*
* Check if we have controllable resets. If either rstctrl is non-zero
* or OMAP_PRM_HAS_RSTCTRL flag is set, we have reset control register
* for the domain.
*/
if (!prm->data->rstctrl && !(prm->data->flags & OMAP_PRM_HAS_RSTCTRL))
return 0;
/* Check if we have the pdata callbacks in place */
if (!pdata || !pdata->clkdm_lookup || !pdata->clkdm_deny_idle ||
!pdata->clkdm_allow_idle)
return -EINVAL;
map = prm->data->rstmap;
if (!map)
return -EINVAL;
reset = devm_kzalloc(&pdev->dev, sizeof(*reset), GFP_KERNEL);
if (!reset)
return -ENOMEM;
reset->rcdev.owner = THIS_MODULE;
reset->rcdev.ops = &omap_reset_ops;
reset->rcdev.of_node = pdev->dev.of_node;
reset->rcdev.nr_resets = OMAP_MAX_RESETS;
reset->rcdev.of_xlate = omap_prm_reset_xlate;
reset->rcdev.of_reset_n_cells = 1;
reset->dev = &pdev->dev;
spin_lock_init(&reset->lock);
reset->prm = prm;
sprintf(buf, "%s_clkdm", prm->data->clkdm_name ? prm->data->clkdm_name :
prm->data->name);
if (!(prm->data->flags & OMAP_PRM_HAS_NO_CLKDM)) {
reset->clkdm = pdata->clkdm_lookup(buf);
if (!reset->clkdm)
return -EINVAL;
}
while (map->rst >= 0) {
reset->mask |= BIT(map->rst);
map++;
}
return devm_reset_controller_register(&pdev->dev, &reset->rcdev);
}
static int omap_prm_probe(struct platform_device *pdev)
{
struct resource *res;
const struct omap_prm_data *data;
struct omap_prm *prm;
const struct of_device_id *match;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENODEV;
match = of_match_device(omap_prm_id_table, &pdev->dev);
if (!match)
return -ENOTSUPP;
prm = devm_kzalloc(&pdev->dev, sizeof(*prm), GFP_KERNEL);
if (!prm)
return -ENOMEM;
data = match->data;
while (data->base != res->start) {
if (!data->base)
return -EINVAL;
data++;
}
prm->data = data;
prm->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(prm->base))
return PTR_ERR(prm->base);
return omap_prm_reset_init(pdev, prm);
}
static struct platform_driver omap_prm_driver = {
.probe = omap_prm_probe,
.driver = {
.name = KBUILD_MODNAME,
.of_match_table = omap_prm_id_table,
},
};
builtin_platform_driver(omap_prm_driver);