The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x f71f6ff8c1f682a1cae4e8d7bdeed9d7f76b8f75 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023123002-partridge-speech-5e07@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

f71f6ff8c1f6 ("bus: ti-sysc: Flush posted write only after srst_udelay") d929b2b7464f ("bus: ti-sysc: Use fsleep() instead of usleep_range() in sysc_reset()") 34539b442b3b ("bus: ti-sysc: Flush posted write on enable before reset") ab4d309d8708 ("bus: ti-sysc: Improve reset to work with modules with no sysconfig") e64c021fd924 ("bus: ti-sysc: Rename clk related quirks to pre_reset and post_reset quirks") aec551c7a00f ("bus: ti-sysc: Fix 1-wire reset quirk") e709ed70d122 ("bus: ti-sysc: Fix missing reset delay handling") 020003f763e2 ("bus: ti-sysc: Add module enable quirk for audio AESS")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f71f6ff8c1f682a1cae4e8d7bdeed9d7f76b8f75 Mon Sep 17 00:00:00 2001 From: Tony Lindgren tony@atomide.com Date: Fri, 24 Nov 2023 10:50:56 +0200 Subject: [PATCH] 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

diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c index d57bc066dce6..9ed9239b1228 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);