[PATCH] bus: ti-sysc: Fix external abort for am335x pruss probe

[Tony Lindgren]

Starting with v5.15-rc1, I'm now seeing am335x beaglebone black produce
the following error on pruss probe:

Unhandled fault: external abort on non-linefetch (0x1008) at 0xe0326000

This seems to have started with the enabling of pruss for am335x in the
dts files. Adding a read-back after write to the sysconfig register fixes
the issue for me.

Cc: Suman Anna <s-anna@xxxxxx>
Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
---
 drivers/bus/ti-sysc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -2037,6 +2037,9 @@ 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 */
+		sysc_read_sysconfig(ddata);
 	}
 
 	if (ddata->cfg.srst_udelay)
-- 
2.33.0