Xing,Yes, the pclk_vio_grf is needed for doing video output.
On Sun, Jun 12, 2016 at 2:48 AM, Xing Zheng<zhengxing@xxxxxxxxxxxxxx> wrote:
The pclk_vio_grf supply power for GRF IOs, if it is disabled, willThis clock is only needed when doing video output (like eDP), right?
cause abnormal operation of the GRF.
The clock tree of the pclk_vio like this:
| --> pclk_vio_grf
... pclk_vio | --> pclk_mipi_dsi1
| --> pclk_mipi_dsi0
and the pclk_mipi_dsi0 and pclk_mipi_dsi1 don't have the flag
CLK_IGNORE_UNUSED, and they will be disabled by clk_disable_unused
when startup:
clk_disable_unused
--> clk_disable_unprepare
--> clk_disable
--> clk_core_disable(core->parent)
then, the pclk_vio_grf also is disabled. Therefore, we need to add
pclk_vio_grf to critical clock and avoid to disable pclk_vio and
pclk_vio_grf.
Tested-by: Yakir Yang<ykk@xxxxxxxxxxxxxx>
Signed-off-by: Yakir Yang<ykk@xxxxxxxxxxxxxx>
Signed-off-by: Brian Norris<briannorris@xxxxxxxxxxxx>
Signed-off-by: Xing Zheng<zhengxing@xxxxxxxxxxxxxx>
---
drivers/clk/rockchip/clk-rk3399.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/clk/rockchip/clk-rk3399.c b/drivers/clk/rockchip/clk-rk3399.c
index b6742fa..7ecb12c3 100644
--- a/drivers/clk/rockchip/clk-rk3399.c
+++ b/drivers/clk/rockchip/clk-rk3399.c
@@ -1485,6 +1485,7 @@ static const char *const rk3399_cru_critical_clocks[] __initconst = {
"gpll_hclk_perilp1_src",
"gpll_aclk_perilp0_src",
"gpll_aclk_perihp_src",
+ "pclk_vio_grf",
That means it is not really a critical clock. Critical clocks are
supposed to be ones that are needed for the basic functioning of the
system and that can never be turned off in any circumstances. In this
case, if someone were running a rk3399 device and didn't have any
video output they would want this clock off.
Can you figure out in exactly which circumstances this clock needs to
be on and then add a proper consumer of this clock? For instance, if
this clock is needed whenever the VOP is outputting data, then the VOP
should be a client and should turn this clock on and off when video is
being output. If this clock is needed whenever you access VOP
registers, then the VOP should be a client and turn this clock on
around register accesses.
-Doug