| Message ID | 20180705142319.19583-5-faiz_abbas@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Faiz Abbas <faiz_abbas@ti.com> [180705 14:24]: > +static int sysc_reset(struct sysc *ddata) > +{ > + int offset = ddata->offsets[SYSC_SYSCONFIG]; > + int val = sysc_read(ddata, offset); Can you please just warn and return early for now if no syss_mask is specified? Otherwise we'll have mysterious errors if somebody leaves out "ti,hwmods" for module types we do not yet support reset for. > + val |= (0x1 << ddata->cap->regbits->srst_shift); > + sysc_write(ddata, offset, val); > + > + /* Poll on reset status */ > + if (ddata->cfg.syss_mask) { > + 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); > + } > + > + return 0; > +} > + Otherwise looks good to me. Thanks, Tony
Hi, On Thursday 05 July 2018 09:17 PM, Tony Lindgren wrote: > * Faiz Abbas <faiz_abbas@ti.com> [180705 14:24]: >> +static int sysc_reset(struct sysc *ddata) >> +{ >> + int offset = ddata->offsets[SYSC_SYSCONFIG]; >> + int val = sysc_read(ddata, offset); > > Can you please just warn and return early for now if no > syss_mask is specified? Otherwise we'll have mysterious > errors if somebody leaves out "ti,hwmods" for module types > we do not yet support reset for. RESET write to sysconfig can still happen even if there's no syss_mask right? Not all modules need to poll on reset status. Thanks, Faiz
* Faiz Abbas <faiz_abbas@ti.com> [180706 10:05]: > Hi, > > On Thursday 05 July 2018 09:17 PM, Tony Lindgren wrote: > > * Faiz Abbas <faiz_abbas@ti.com> [180705 14:24]: > >> +static int sysc_reset(struct sysc *ddata) > >> +{ > >> + int offset = ddata->offsets[SYSC_SYSCONFIG]; > >> + int val = sysc_read(ddata, offset); > > > > Can you please just warn and return early for now if no > > syss_mask is specified? Otherwise we'll have mysterious > > errors if somebody leaves out "ti,hwmods" for module types > > we do not yet support reset for. > > RESET write to sysconfig can still happen even if there's no syss_mask > right? Not all modules need to poll on reset status. It can but we currently don't have anything similar to srst_udelay like we have in _ocp_softreset(). And we don't currently have suport for sysc reset done bit. So we want to warn and return error except in the known working case for now. Regards, Tony
Hi, On Friday 06 July 2018 04:05 PM, Tony Lindgren wrote: > * Faiz Abbas <faiz_abbas@ti.com> [180706 10:05]: >> Hi, >> >> On Thursday 05 July 2018 09:17 PM, Tony Lindgren wrote: >>> * Faiz Abbas <faiz_abbas@ti.com> [180705 14:24]: >>>> +static int sysc_reset(struct sysc *ddata) >>>> +{ >>>> + int offset = ddata->offsets[SYSC_SYSCONFIG]; >>>> + int val = sysc_read(ddata, offset); >>> >>> Can you please just warn and return early for now if no >>> syss_mask is specified? Otherwise we'll have mysterious >>> errors if somebody leaves out "ti,hwmods" for module types >>> we do not yet support reset for. >> >> RESET write to sysconfig can still happen even if there's no syss_mask >> right? Not all modules need to poll on reset status. > > It can but we currently don't have anything similar to > srst_udelay like we have in _ocp_softreset(). And we don't > currently have suport for sysc reset done bit. > > So we want to warn and return error except in the known > working case for now. > Ok. Thanks, Faiz
diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c index ad1cd6888757..ac65a4f336d5 100644 --- a/drivers/bus/ti-sysc.c +++ b/drivers/bus/ti-sysc.c @@ -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 +951,26 @@ static void sysc_init_revision_quirks(struct sysc *ddata) } } +static int sysc_reset(struct sysc *ddata) +{ + int offset = ddata->offsets[SYSC_SYSCONFIG]; + int val = sysc_read(ddata, offset); + + val |= (0x1 << ddata->cap->regbits->srst_shift); + sysc_write(ddata, offset, val); + + /* Poll on reset status */ + if (ddata->cfg.syss_mask) { + 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); + } + + return 0; +} + /* At this point the module is configured enough to read the revision */ static int sysc_init_module(struct sysc *ddata) { @@ -960,6 +988,17 @@ static int sysc_init_module(struct sysc *ddata) return 0; } + if (!(ddata->cfg.quirks & SYSC_QUIRK_NO_RESET_ON_INIT) && + !ddata->legacy_mode) { + 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);
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> --- drivers/bus/ti-sysc.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+)