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

bus: ti-sysc: Add support for software reset 

Add support for the software reset of a target interconnect
module using its sysconfig and sysstatus registers.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
[tony@atomide.com: updated to check if sysconfig exists]
Signed-off-by: Tony Lindgren <tony@atomide.com>
hifive-unleashed-5.1
Faiz Abbas 2018-07-09 22:18:39 +05:30 committed by Tony Lindgren
parent 7f35e63dbf
commit 596e795569
1 changed files with 46 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

46
drivers/bus/ti-sysc.c
View File

@ -23,11 +23,14 @@
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/slab.h>
#include <linux/iopoll.h>
#include <linux/platform_data/ti-sysc.h>
#include <dt-bindings/bus/ti-sysc.h>
#define MAX_MODULE_SOFTRESET_WAIT 10000
static const char * const reg_names[] = { "rev", "sysc", "syss", };
enum sysc_clocks {
@ -88,6 +91,11 @@ struct sysc {
struct delayed_work idle_work;
};
void sysc_write(struct sysc *ddata, int offset, u32 value)
{
writel_relaxed(value, ddata->module_va + offset);
}
static u32 sysc_read(struct sysc *ddata, int offset)
{
if (ddata->cfg.quirks & SYSC_QUIRK_16BIT) {
@ -943,6 +951,36 @@ static void sysc_init_revision_quirks(struct sysc *ddata)
}
}
static int sysc_reset(struct sysc *ddata)
{
int offset = ddata->offsets[SYSC_SYSCONFIG];
int val;
if (ddata->legacy_mode || offset < 0 ||
ddata->cfg.quirks & SYSC_QUIRK_NO_RESET_ON_INIT)
return 0;
/*
* Currently only support reset status in sysstatus.
* Warn and return error in all other cases
*/
if (!ddata->cfg.syss_mask) {
dev_err(ddata->dev, "No ti,syss-mask. Reset failed\n");
return -EINVAL;
}
val = sysc_read(ddata, offset);
val |= (0x1 << ddata->cap->regbits->srst_shift);
sysc_write(ddata, offset, val);
/* Poll on reset status */
offset = ddata->offsets[SYSC_SYSSTATUS];
return readl_poll_timeout(ddata->module_va + offset, val,
(val & ddata->cfg.syss_mask) == 0x0,
100, MAX_MODULE_SOFTRESET_WAIT);
}
/* At this point the module is configured enough to read the revision */
static int sysc_init_module(struct sysc *ddata)
{
@ -960,6 +998,14 @@ static int sysc_init_module(struct sysc *ddata)
return 0;
}
error = sysc_reset(ddata);
if (error) {
dev_err(ddata->dev, "Reset failed with %d\n", error);
pm_runtime_put_sync(ddata->dev);
return error;
}
ddata->revision = sysc_read_revision(ddata);
pm_runtime_put_sync(ddata->dev);