[PATCH] ARM: tegra114: correctly output clk_32k

[PATCH] ARM: tegra114: correctly output clk_32k

[Alexandre Courbot]

Tegra has a blink timer register that allows to modulate the
clk_32k clock before outputting it. Since clk_32k is presented to the
kernel as a fixed clock, make sure this register does not tamper with
the clock frequency and that clk_32k is outputted as-is, similarly to
what is done on t20 and t30.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
---
 drivers/clk/tegra/clk-tegra114.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/clk/tegra/clk-tegra114.c b/drivers/clk/tegra/clk-tegra114.c
index d78e16e..dc76d67 100644
--- a/drivers/clk/tegra/clk-tegra114.c
+++ b/drivers/clk/tegra/clk-tegra114.c
@@ -127,6 +127,7 @@
 #define PMC_DPD_PADS_ORIDE_BLINK_ENB 20
 #define PMC_CTRL 0
 #define PMC_CTRL_BLINK_ENB 7
+#define PMC_BLINK_TIMER 0x40
 
 #define OSC_CTRL			0x50
 #define OSC_CTRL_OSC_FREQ_SHIFT		28
@@ -1625,6 +1626,8 @@ static void __init tegra114_pmc_clk_init(void __iomem *pmc_base)
 	clks[clk_out_3] = clk;
 
 	/* blink */
+	/* clear the blink timer register to directly output clk_32k */
+	writel_relaxed(0, pmc_base + PMC_BLINK_TIMER);
 	clk = clk_register_gate(NULL, "blink_override", "clk_32k", 0,
 				pmc_base + PMC_DPD_PADS_ORIDE,
 				PMC_DPD_PADS_ORIDE_BLINK_ENB, 0, NULL);
-- 
1.8.2.3

Re: [PATCH] ARM: tegra114: correctly output clk_32k

[Stephen Warren]

On 05/24/2013 01:10 AM, Alexandre Courbot wrote:
> Tegra has a blink timer register that allows to modulate the
> clk_32k clock before outputting it. Since clk_32k is presented to the
> kernel as a fixed clock, make sure this register does not tamper with
> the clock frequency and that clk_32k is outputted as-is, similarly to
> what is done on t20 and t30.

drivers/clk changes should go to Mike Turquette now that there aren't
any inter-dependencies between core Tegra and Tegra clk driver patches.

I CC'd him here, but perhaps he'll want this resent if he doesn't have
the original email still.

Acked-by: Stephen Warren <swarren@nvidia.com>

Re: [PATCH] ARM: tegra114: correctly output clk_32k

[Alexandre Courbot]

On Sat, May 25, 2013 at 12:30 AM, Stephen Warren <swarren@wwwdotorg.org> wrote:
> On 05/24/2013 01:10 AM, Alexandre Courbot wrote:
>> Tegra has a blink timer register that allows to modulate the
>> clk_32k clock before outputting it. Since clk_32k is presented to the
>> kernel as a fixed clock, make sure this register does not tamper with
>> the clock frequency and that clk_32k is outputted as-is, similarly to
>> what is done on t20 and t30.
>
> drivers/clk changes should go to Mike Turquette now that there aren't
> any inter-dependencies between core Tegra and Tegra clk driver patches.
>
> I CC'd him here, but perhaps he'll want this resent if he doesn't have
> the original email still.

I just resent the patch to make things easier.

Thanks,
Alex.