redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

soc: ti: omap-prm: add support for denying idle for reset clockdomain

Browse source 
TI SoCs hardware reset signals require the parent clockdomain to be
in force wakeup mode while de-asserting the reset, otherwise it may
never complete. To support this, add pdata hooks to control the
clockdomain directly.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
This commit is contained in:
Tero Kristo 2019-10-09 08:55:38 -07:00 committed by Santosh Shilimkar
parent c5117a78dd
commit d30cd83f68
2 changed files with 55 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

36
drivers/soc/ti/omap_prm.c
View file

@ -16,6 +16,8 @@
#include <linux/reset-controller.h>
#include <linux/delay.h>
#include <linux/platform_data/ti-prm.h>
struct omap_rst_map {
s8 rst;
s8 st;
@ -24,6 +26,7 @@ struct omap_rst_map {
struct omap_prm_data {
u32 base;
const char *name;
const char *clkdm_name;
u16 rstctrl;
u16 rstst;
const struct omap_rst_map *rstmap;
@ -40,6 +43,8 @@ struct omap_reset_data {
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)
@ -49,6 +54,7 @@ struct omap_reset_data {
#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)
@ -133,6 +139,8 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
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);
@ -145,6 +153,9 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
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);
@ -153,7 +164,7 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
spin_unlock_irqrestore(&reset->lock, flags);
if (!has_rstst)
return 0;
goto exit;
/* wait for the status to be set */
ret = readl_relaxed_poll_timeout(reset->prm->base +
@ -164,7 +175,11 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev,
pr_err("%s: timedout waiting for %s:%lu\n", __func__,
reset->prm->data->name, id);
return 0;
exit:
if (reset->clkdm)
pdata->clkdm_allow_idle(reset->clkdm);
return ret;
}
static const struct reset_control_ops omap_reset_ops = {
@ -189,6 +204,8 @@ static int omap_prm_reset_init(struct platform_device *pdev,
{
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
@ -198,6 +215,11 @@ static int omap_prm_reset_init(struct platform_device *pdev,
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;
@ -212,10 +234,20 @@ static int omap_prm_reset_init(struct platform_device *pdev,
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++;

21
include/linux/platform_data/ti-prm.h Normal file
View file

@ -0,0 +1,21 @@
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* TI PRM (Power & Reset Manager) platform data
*
* Copyright (C) 2019 Texas Instruments, Inc.
*
* Tero Kristo <t-kristo@ti.com>
*/
#ifndef _LINUX_PLATFORM_DATA_TI_PRM_H
#define _LINUX_PLATFORM_DATA_TI_PRM_H
struct clockdomain;
struct ti_prm_platform_data {
void (*clkdm_deny_idle)(struct clockdomain *clkdm);
void (*clkdm_allow_idle)(struct clockdomain *clkdm);
struct clockdomain * (*clkdm_lookup)(const char *name);
};
#endif /* _LINUX_PLATFORM_DATA_TI_PRM_H */