diff options
| author | Tony Lindgren <tony@atomide.com> | 2023-11-24 10:50:56 +0200 |
|---|---|---|
| committer | Tony Lindgren <tony@atomide.com> | 2023-11-28 12:57:16 +0200 |
| commit | f71f6ff8c1f682a1cae4e8d7bdeed9d7f76b8f75 (patch) | |
| tree | ae375ae58c46d03bd14a1d203933349abe895d7f /drivers/bus | |
| parent | b85ea95d086471afb4ad062012a4d73cd328fa86 (diff) | |
| download | linux-f71f6ff8c1f682a1cae4e8d7bdeed9d7f76b8f75.tar.gz | |
bus: ti-sysc: Flush posted write only after srst_udelay
Commit 34539b442b3b ("bus: ti-sysc: Flush posted write on enable before
reset") caused a regression reproducable on omap4 duovero where the ISS
target module can produce interconnect errors on boot. Turns out the
registers are not accessible until after a delay for devices needing
a ti,sysc-delay-us value.
Let's fix this by flushing the posted write only after the reset delay.
We do flushing also for ti,sysc-delay-us using devices as that should
trigger an interconnect error if the delay is not properly configured.
Let's also add some comments while at it.
Fixes: 34539b442b3b ("bus: ti-sysc: Flush posted write on enable before reset")
Cc: stable@vger.kernel.org
Signed-off-by: Tony Lindgren <tony@atomide.com>
Diffstat (limited to 'drivers/bus')
| -rw-r--r-- | drivers/bus/ti-sysc.c | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c index d57bc066dce6b..9ed9239b1228f 100644 --- a/drivers/bus/ti-sysc.c +++ b/drivers/bus/ti-sysc.c @@ -2158,13 +2158,23 @@ static int sysc_reset(struct sysc *ddata) sysc_val = sysc_read_sysconfig(ddata); sysc_val |= sysc_mask; sysc_write(ddata, sysc_offset, sysc_val); - /* Flush posted write */ + + /* + * Some devices need a delay before reading registers + * after reset. Presumably a srst_udelay is not needed + * for devices that use a rstctrl register reset. + */ + if (ddata->cfg.srst_udelay) + fsleep(ddata->cfg.srst_udelay); + + /* + * Flush posted write. For devices needing srst_udelay + * this should trigger an interconnect error if the + * srst_udelay value is needed but not configured. + */ sysc_val = sysc_read_sysconfig(ddata); } - if (ddata->cfg.srst_udelay) - fsleep(ddata->cfg.srst_udelay); - if (ddata->post_reset_quirk) ddata->post_reset_quirk(ddata); |