diff options
| author | Joseph Lo <josephl@nvidia.com> | 2015-04-29 17:14:03 +0800 |
|---|---|---|
| committer | Patrick Georgi <pgeorgi@google.com> | 2015-05-18 13:16:33 +0200 |
| commit | 589e63ee7c302a96ef7f9349838936dccdb19f52 (patch) | |
| tree | 6d47a03042cafdbbbce6fdee5139b9ac818131f2 /src/drivers/gic | |
| parent | b7d0ffd1edb358c089c0fe94711aac65eeb81d6a (diff) | |
drivers/gic: reprogram the GIC CPU interface to bypass IRQ
GICv2 provides a wake IRQ/FIQ (for wake-event purpose), which are not
disabled by GIC CPU interface. This is done by adding a bypass override
capability when the interrupts are disabled at the CPU interface. To
support this, there are four bits about IRQ/FIQ BypassDisable in CPU
interface Control Register. So the CPU can exit from WFI when an
asserted IRQ is coming. This is critical for power gating a CPU.
BRANCH=none
BUG=chrome-os-partner:39620
TEST=testing with CPU idle with power down state support and CPU can
wake up normally
Change-Id: I71ac642e28024a562db898665b74a5791fce325a
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 3a3f098cbf3fbfdab8150ebd4fd688fdb472b529
Original-Change-Id: I20569a18f34a4b11b8c8c67ea255b3d0f021839f
Original-Signed-off-by: Joseph Lo <josephl@nvidia.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/269116
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/10172
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src/drivers/gic')
| -rw-r--r-- | src/drivers/gic/gic.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/src/drivers/gic/gic.c b/src/drivers/gic/gic.c index 71073a580a..b7bce2a371 100644 --- a/src/drivers/gic/gic.c +++ b/src/drivers/gic/gic.c @@ -26,6 +26,10 @@ enum { ENABLE_GRP0 = 0x1 << 0, ENABLE_GRP1 = 0x1 << 1, + FIQ_BYP_DIS_GRP0 = 0x1 << 5, + IRQ_BYP_DIS_GRP0 = 0x1 << 6, + FIQ_BYP_DIS_GRP1 = 0x1 << 7, + IRQ_BYP_DIS_GRP1 = 0x1 << 8, }; struct gic { @@ -135,6 +139,13 @@ void gic_disable(void) /* Disable secure, non-secure interrupts. */ uint32_t val = gic_read(&gicc->ctlr); val &= ~(ENABLE_GRP0 | ENABLE_GRP1); + /* + * Enable the IRQ/FIQ BypassDisable bits to bypass the IRQs. + * So the CPU can wake up from power gating state when the GIC + * was disabled. + */ + val |= FIQ_BYP_DIS_GRP0 | IRQ_BYP_DIS_GRP0 | + FIQ_BYP_DIS_GRP1 | IRQ_BYP_DIS_GRP1; gic_write(&gicc->ctlr, val); } |