Linux-RISC-V Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Alex Elder <elder@riscstar.com>
To: mturquette@baylibre.com, sboyd@kernel.org
Cc: dlan@gentoo.org, heylenay@4d2.org, inochiama@outlook.com,
	elder@riscstar.com, linux-clk@vger.kernel.org,
	spacemit@lists.linux.dev, linux-riscv@lists.infradead.org,
	linux-kernel@vger.kernel.org, Guodong Xu <guodong@riscstar.com>
Subject: [PATCH] clk: spacemit: mark K1 pll1_d8 as critical
Date: Sat,  7 Jun 2025 15:27:58 -0500	[thread overview]
Message-ID: <20250607202759.4180579-1-elder@riscstar.com> (raw)

The pll1_d8 clock is enabled by the boot loader, and is ultimately a
parent for numerous clocks.  Guodong Xu was recently testing DMA,
adding a reset property, and discovered that the needed reset was
not yet ready during initial probe.  It dropped its clock reference,
which dropped parent references, and along the way it dropped the sole
reference to pll1_d8 (from its prior clk_get()).  Clock pll1_d8 got
disabled, which resulted in a non-functioning system.

Mark that clock critical so it doesn't get turned off in this case.
We might be able to turn this flag off someday, but for now it
resolves the problem Guodong encountered.

Define a new macro CCU_FACTOR_GATE_DEFINE() to allow clock flags to
be supplied for a CCU_FACTOR_GATE clock.

Fixes: 1b72c59db0add ("clk: spacemit: Add clock support for SpacemiT K1 SoC")
Signed-off-by: Alex Elder <elder@riscstar.com>
Tested-by: Guodong Xu <guodong@riscstar.com>
---
 drivers/clk/spacemit/ccu-k1.c  |  3 ++-
 drivers/clk/spacemit/ccu_mix.h | 21 +++++++++++++--------
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/drivers/clk/spacemit/ccu-k1.c b/drivers/clk/spacemit/ccu-k1.c
index cdde37a052353..df65009a07bb1 100644
--- a/drivers/clk/spacemit/ccu-k1.c
+++ b/drivers/clk/spacemit/ccu-k1.c
@@ -170,7 +170,8 @@ CCU_FACTOR_GATE_DEFINE(pll1_d4, CCU_PARENT_HW(pll1), APBS_PLL1_SWCR2, BIT(3), 4,
 CCU_FACTOR_GATE_DEFINE(pll1_d5, CCU_PARENT_HW(pll1), APBS_PLL1_SWCR2, BIT(4), 5, 1);
 CCU_FACTOR_GATE_DEFINE(pll1_d6, CCU_PARENT_HW(pll1), APBS_PLL1_SWCR2, BIT(5), 6, 1);
 CCU_FACTOR_GATE_DEFINE(pll1_d7, CCU_PARENT_HW(pll1), APBS_PLL1_SWCR2, BIT(6), 7, 1);
-CCU_FACTOR_GATE_DEFINE(pll1_d8, CCU_PARENT_HW(pll1), APBS_PLL1_SWCR2, BIT(7), 8, 1);
+CCU_FACTOR_GATE_FLAGS_DEFINE(pll1_d8, CCU_PARENT_HW(pll1), APBS_PLL1_SWCR2, BIT(7), 8, 1,
+		CLK_IS_CRITICAL);
 CCU_FACTOR_GATE_DEFINE(pll1_d11_223p4, CCU_PARENT_HW(pll1), APBS_PLL1_SWCR2, BIT(15), 11, 1);
 CCU_FACTOR_GATE_DEFINE(pll1_d13_189, CCU_PARENT_HW(pll1), APBS_PLL1_SWCR2, BIT(16), 13, 1);
 CCU_FACTOR_GATE_DEFINE(pll1_d23_106p8, CCU_PARENT_HW(pll1), APBS_PLL1_SWCR2, BIT(20), 23, 1);
diff --git a/drivers/clk/spacemit/ccu_mix.h b/drivers/clk/spacemit/ccu_mix.h
index 51d19f5d6aacb..668c8139339e1 100644
--- a/drivers/clk/spacemit/ccu_mix.h
+++ b/drivers/clk/spacemit/ccu_mix.h
@@ -101,16 +101,21 @@ static struct ccu_mix _name = {							\
 	}									\
 }
 
+#define CCU_FACTOR_GATE_FLAGS_DEFINE(_name, _parent, _reg_ctrl, _mask_gate, _div,	\
+			       _mul, _flags)					\
+struct ccu_mix _name = {							\
+	.gate	= CCU_GATE_INIT(_mask_gate),					\
+	.factor	= CCU_FACTOR_INIT(_div, _mul),					\
+	.common = {								\
+		.reg_ctrl	= _reg_ctrl,					\
+		CCU_MIX_INITHW(_name, _parent, spacemit_ccu_factor_gate_ops, _flags)	\
+	}									\
+}
+
 #define CCU_FACTOR_GATE_DEFINE(_name, _parent, _reg_ctrl, _mask_gate, _div,	\
 			       _mul)						\
-static struct ccu_mix _name = {							\
-	.gate	= CCU_GATE_INIT(_mask_gate),					\
-	.factor	= CCU_FACTOR_INIT(_div, _mul),					\
-	.common = {								\
-		.reg_ctrl	= _reg_ctrl,					\
-		CCU_MIX_INITHW(_name, _parent, spacemit_ccu_factor_gate_ops, 0)	\
-	}									\
-}
+	CCU_FACTOR_GATE_FLAGS_DEFINE(_name, _parent, _reg_ctrl, _mask_gate, _div,	\
+			       _mul, 0)
 
 #define CCU_MUX_GATE_DEFINE(_name, _parents, _reg_ctrl, _shift, _width,		\
 			    _mask_gate, _flags)					\
-- 
2.45.2


_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

             reply	other threads:[~2025-06-07 20:43 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-06-07 20:27 Alex Elder [this message]
2025-06-08  0:24 ` [PATCH] clk: spacemit: mark K1 pll1_d8 as critical Yixun Lan
2025-06-08  2:46   ` Alex Elder
2025-06-08  4:46     ` Haylen Chu
2025-06-08 12:56       ` Yixun Lan
2025-06-08 18:31       ` Alex Elder
2025-06-09  4:21         ` Haylen Chu
2025-06-08 19:30 ` kernel test robot
  -- strict thread matches above, loose matches on Subject: below --
2025-06-09 20:08 Alex Elder
2025-06-09 20:14 ` Alex Elder
2025-06-10  2:24 ` Haylen Chu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20250607202759.4180579-1-elder@riscstar.com \
    --to=elder@riscstar.com \
    --cc=dlan@gentoo.org \
    --cc=guodong@riscstar.com \
    --cc=heylenay@4d2.org \
    --cc=inochiama@outlook.com \
    --cc=linux-clk@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=mturquette@baylibre.com \
    --cc=sboyd@kernel.org \
    --cc=spacemit@lists.linux.dev \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox