Re: [PATCH v6 2/3] clk: qcom: Add support for BRANCH_NO_DELAY flag for branch clocks

Stephen Boyd
2018-05-02T07:14:39Z

Quoting Amit Nischal (2018-04-30 09:20:09)
> diff --git a/drivers/clk/qcom/clk-branch.h b/drivers/clk/qcom/clk-branch.h
> index 284df3f..5d621f3 100644
> --- a/drivers/clk/qcom/clk-branch.h
> +++ b/drivers/clk/qcom/clk-branch.h
> @@ -42,6 +42,7 @@ struct clk_branch {
> #define BRANCH_HALT_ENABLE 1 /* pol: 0 =3D halt */
> #define BRANCH_HALT_ENABLE_VOTED (BRANCH_HALT_ENABLE | BRANCH_VOTE=
D)
> #define BRANCH_HALT_DELAY 2 /* No bit to check; just delay =
*/
> +#define BRANCH_NO_DELAY 3 /* No bit to check; wit=
hout delay */

Let's call it BRANCH_HALT_SKIP and indicate that it's skipping the halt
bit check. Technically there is a bit to check, we just refuse to check
it. I've reworked and applied this patch as below.

From=20f9ddbd74bf4940d3b7a0eb076eb254833660643c Mon Sep 17 00:00:00 2001
From: Amit Nischal <anischal@codeaurora.org>
Date: Mon, 30 Apr 2018 21:50:09 +0530
Subject: [PATCH] clk: qcom: Add support for BRANCH_HALT_SKIP flag for branch
clocks

There could be few clocks where the clock status bit is not
required to be polled as the clock on/off would be controlled
by enabling/disabling external source. Add support for the
same by introducing new flag named as 'BRANCH_HALT_SKIP'.

Signed-off-by: Amit Nischal <anischal@codeaurora.org>
[sboyd@kernel.org: Rename flag to BRANCH_HALT_SKIP]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
---
drivers/clk/qcom/clk-branch.c | 7 +++++--
drivers/clk/qcom/clk-branch.h | 1 +
2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/qcom/clk-branch.c b/drivers/clk/qcom/clk-branch.c
index 26f7af315066..c58c5538b1b6 100644
--- a/drivers/clk/qcom/clk-branch.c
+++ b/drivers/clk/qcom/clk-branch.c
@@ -77,8 +77,11 @@ static int clk_branch_wait(const struct clk_branch *br, =
bool enabling,
bool voted =3D br->halt_check & BRANCH_VOTED;
const char *name =3D clk_hw_get_name(&br->clkr.hw);
=

- /* Skip checking halt bit if the clock is in hardware gated mode */
- if (clk_branch_in_hwcg_mode(br))
+ /*
+ * Skip checking halt bit if we're explicitly ignoring the bit or the
+ * clock is in hardware gated mode
+ */
+ if (br->halt_check =3D=3D BRANCH_HALT_SKIP || clk_branch_in_hwcg_mode(br))
return 0;
=

if (br->halt_check =3D=3D BRANCH_HALT_DELAY || (!enabling && voted)) {
diff --git a/drivers/clk/qcom/clk-branch.h b/drivers/clk/qcom/clk-branch.h
index 284df3f3c55f..1702efb1c511 100644
--- a/drivers/clk/qcom/clk-branch.h
+++ b/drivers/clk/qcom/clk-branch.h
@@ -42,6 +42,7 @@ struct clk_branch {
#define BRANCH_HALT_ENABLE 1 /* pol: 0 =3D halt */
#define BRANCH_HALT_ENABLE_VOTED (BRANCH_HALT_ENABLE | BRANCH_VOTED)
#define BRANCH_HALT_DELAY 2 /* No bit to check; just delay */
+#define BRANCH_HALT_SKIP 3 /* Don't check halt bit */
=

struct clk_regmap clkr;
};
-- =

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