mb/google/brya/acpi: Update GPIO polling method
The preferred way of polling in ACPI I've seen is usually to just
divide the sleep into N chunks, and ignore the time taken in between.
This works in practice (validated with Timer calls before and after).
Signed-off-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Change-Id: I4a2cd82cea05c539eff30b9b9d6ef18550d17686
Reviewed-on: https://review.coreboot.org/c/coreboot/+/65484
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Robert Zieba <robertzieba@google.com>
Reviewed-by: Subrata Banik <subratabanik@google.com>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
diff --git a/src/mainboard/google/brya/acpi/utility.asl b/src/mainboard/google/brya/acpi/utility.asl
index 4fc03e8..1999d33 100644
--- a/src/mainboard/google/brya/acpi/utility.asl
+++ b/src/mainboard/google/brya/acpi/utility.asl
@@ -8,14 +8,22 @@
*/
Method (GPPL, 3, Serialized)
{
- Local0 = GRXS (Arg0)
- Local7 = Arg2 * 10000
- Local7 = Timer + Local7
- While (Local0 != Arg1 && Timer < Local7)
+ Local0 = 0
+ While (Local0 < Arg2)
{
- Stall (10)
- Local0 = \_SB.PCI0.GRXS (Arg0)
+ If (\_SB.PCI0.GRXS (Arg0) == Arg1) {
+ Return (0)
+ } Else {
+ Local0++
+ }
+ Sleep (1)
}
+
+ If (Local0 == Arg2) {
+ Printf("[ERROR] GPPL for %o timed out", Arg0)
+ }
+
+ Return (0xFF)
}
/* Convert from 32-bit integer to 4-byte buffer (little-endian) */