diff mbox series

[4/4] clk: bcm2835: Mark PLLD_PER as CRITICAL

Message ID 1566145424-3186-5-git-send-email-wahrenst@gmx.net (mailing list archive)
State Accepted, archived
Headers show
Series clk: bcm2835: Add bcm2711 support | expand

Commit Message

Stefan Wahren Aug. 18, 2019, 4:23 p.m. UTC 
The VPU firmware assume that the PLLD_PER isn't modified by the ARM core.
Otherwise this could cause firmware lookups. So mark the clock as critical
to avoid this.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
---
 drivers/clk/bcm/clk-bcm2835.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--
2.7.4

Comments

Stephen Boyd Sept. 17, 2019, 5:16 p.m. UTC | #1 
Quoting Stefan Wahren (2019-08-18 09:23:44)
> The VPU firmware assume that the PLLD_PER isn't modified by the ARM core.
> Otherwise this could cause firmware lookups. So mark the clock as critical
> to avoid this.
> 
> Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
> Reviewed-by: Eric Anholt <eric@anholt.net>
> ---

Applied to clk-next
diff mbox series

Patch

diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index fdf672a..802e488 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -1776,6 +1776,11 @@  static const struct bcm2835_clk_desc clk_desc_array[] = {
 		.hold_mask = CM_PLLD_HOLDCORE,
 		.fixed_divider = 1,
 		.flags = CLK_SET_RATE_PARENT),
+	/*
+	 * VPU firmware assumes that PLLD_PER isn't disabled by the ARM core.
+	 * Otherwise this could cause firmware lookups. That's why we mark
+	 * it as critical.
+	 */
 	[BCM2835_PLLD_PER]	= REGISTER_PLL_DIV(
 		SOC_ALL,
 		.name = "plld_per",
@@ -1785,7 +1790,7 @@  static const struct bcm2835_clk_desc clk_desc_array[] = {
 		.load_mask = CM_PLLD_LOADPER,
 		.hold_mask = CM_PLLD_HOLDPER,
 		.fixed_divider = 1,
-		.flags = CLK_SET_RATE_PARENT),
+		.flags = CLK_IS_CRITICAL | CLK_SET_RATE_PARENT),
 	[BCM2835_PLLD_DSI0]	= REGISTER_PLL_DIV(
 		SOC_ALL,
 		.name = "plld_dsi0",