On 10/2/19 5:04 AM, Thierry Reding wrote:
On Tue, Oct 01, 2019 at 03:13:43PM -0600, Stephen Warren wrote:
From: Stephen Warren <swarren@xxxxxxxxxx>
For a little over a year, U-Boot has configured the flow controller to
perform automatic RAM re-repair on off->on power transitions of the CPU
rail1]. This is mandatory for correct operation of Tegra124. However, RAM
re-repair relies on certain clocks, which the kernel must enable and
leave running. The fuse clock is one of those clocks. Enable this clock
so that LP1 power mode (system suspend) operates correctly.
[1] 3cc7942a4ae5 ARM: tegra: implement RAM repair
Reported-by: Jonathan Hunter <jonathanh@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Stephen Warren <swarren@xxxxxxxxxx>
---
drivers/clk/tegra/clk-tegra124.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/clk/tegra/clk-tegra124.c b/drivers/clk/tegra/clk-tegra124.c
index 0224fdc4766f..f53f6315c646 100644
--- a/drivers/clk/tegra/clk-tegra124.c
+++ b/drivers/clk/tegra/clk-tegra124.c
@@ -1291,6 +1291,7 @@ static struct tegra_clk_init_table common_init_table[] __initdata = {
};
static struct tegra_clk_init_table tegra124_init_table[] __initdata = {
+ { TEGRA124_CLK_FUSE, -1, 0, 1 },
I think the correct way to do this these days is to mark the clock as
CRITICAL. Not sure if there's an easy way to do that given that the
clock init table doesn't allow storing flags.
Do you have any good ideas on how to achieve this with the critical flag
instead of forcing the refcount to 1?
Perhaps something like the below would work?
> ...
The following works for me; does this seem like a reasonable approach?
It does set the critical flag for all SoCs, including any that don't
require RAM re-repair. I'm not sure which do; I know it's more than just
Tegra124, but I'm not sure how far back/forward the requirement goes.
diff --git a/drivers/clk/tegra/clk-tegra-periph.c b/drivers/clk/tegra/clk-tegra-periph.c
index 1ed85f120a1b..76dd91eebd13 100644
--- a/drivers/clk/tegra/clk-tegra-periph.c
+++ b/drivers/clk/tegra/clk-tegra-periph.c
@@ -785,7 +785,7 @@ static struct tegra_periph_init_data gate_clks[] = {
GATE("ahbdma", "hclk", 33, 0, tegra_clk_ahbdma, 0),
GATE("apbdma", "pclk", 34, 0, tegra_clk_apbdma, 0),
GATE("kbc", "clk_32k", 36, TEGRA_PERIPH_ON_APB | TEGRA_PERIPH_NO_RESET, tegra_clk_kbc, 0),
- GATE("fuse", "clk_m", 39, TEGRA_PERIPH_ON_APB, tegra_clk_fuse, 0),
+ GATE("fuse", "clk_m", 39, TEGRA_PERIPH_ON_APB, tegra_clk_fuse, CLK_IS_CRITICAL),
GATE("fuse_burn", "clk_m", 39, TEGRA_PERIPH_ON_APB, tegra_clk_fuse_burn, 0),
GATE("kfuse", "clk_m", 40, TEGRA_PERIPH_ON_APB, tegra_clk_kfuse, 0),
GATE("apbif", "clk_m", 107, TEGRA_PERIPH_ON_APB, tegra_clk_apbif, 0),
