[PATCH AUTOSEL 6.17-6.12] clk: clocking-wizard: Fix output clock register offset for Versal platforms

[Sasha Levin]

From: Shubhrajyoti Datta <shubhrajyoti.datta at amd.com>

[ Upstream commit 7c2e86f7b5af93d0e78c16e4359318fe7797671d ]

The output clock register offset used in clk_wzrd_register_output_clocks
was incorrectly referencing 0x3C instead of 0x38, which caused
misconfiguration of output dividers on Versal platforms.

Correcting the off-by-one error ensures proper configuration of output
clocks.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta at amd.com>
Signed-off-by: Stephen Boyd <sboyd at kernel.org>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---

LLM Generated explanations, may be completely bogus:

YES – the change in `drivers/clk/xilinx/clk-xlnx-clock-wizard.c:1120`
moves the Versal per-output divider base from
`WZRD_CLK_CFG_REG(is_versal, 3)` to `... 2`, fixing the off-by-one that
pointed each divider at the wrong MMIO pair.

- With the old offset, `clk_wzrd_ver_register_divider()` handed
  `clk_wzrd_ver_dynamic_reconfig()` a base that skips the first 32-bit
  register. You can see in `clk_wzrd_ver_dynamic_reconfig()`
  (`drivers/clk/xilinx/clk-xlnx-clock-wizard.c:235-262`) that we expect
  `div_addr` to hold the low/high-time bits (`WZRD_CLKFBOUT_PREDIV2`,
  `WZRD_EDGE_SHIFT`, etc.) and we write the high-time value to `div_addr
  + 4`. Starting from `... + 3` caused us to read/write the wrong
  register pair—programming the high-time word first and then trampling
  the next output’s low-time register—so the dividers for every Versal
  output were misconfigured.
- The corrected offset now matches the register map already hard-coded
  elsewhere (e.g., the `DIV_ALL` path in
  `clk_wzrd_dynamic_ver_all_nolock()` uses `WZRD_CLK_CFG_REG(1,
  WZRD_CLKOUT0_1)` where `WZRD_CLKOUT0_1` is 2). That consistency makes
  the fix obviously right and keeps the non-Versal path untouched
  because the change sits under `if (is_versal)`.
- The regression was introduced with Versal support (`Fixes:
  3a96393a46e78`, first in v6.10), so every stable branch carrying that
  commit currently ships broken output clocks; the patch is a tiny,
  self-contained offset adjustment and does not depend on newer
  infrastructure, making it straightforward to backport.

Given the severity (Versal outputs can’t be programmed correctly) and
the minimal, well-scoped fix, this is a strong stable-candidate.
Suggested follow-up: once backported, validate on a Versal board to
confirm the dividers now lock to requested rates.

 drivers/clk/xilinx/clk-xlnx-clock-wizard.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/xilinx/clk-xlnx-clock-wizard.c b/drivers/clk/xilinx/clk-xlnx-clock-wizard.c
index 0295a13a811cf..f209a02e82725 100644
--- a/drivers/clk/xilinx/clk-xlnx-clock-wizard.c
+++ b/drivers/clk/xilinx/clk-xlnx-clock-wizard.c
@@ -1108,7 +1108,7 @@ static int clk_wzrd_register_output_clocks(struct device *dev, int nr_outputs)
 						(dev,
 						 clkout_name, clk_name, 0,
 						 clk_wzrd->base,
-						 (WZRD_CLK_CFG_REG(is_versal, 3) + i * 8),
+						 (WZRD_CLK_CFG_REG(is_versal, 2) + i * 8),
 						 WZRD_CLKOUT_DIVIDE_SHIFT,
 						 WZRD_CLKOUT_DIVIDE_WIDTH,
 						 CLK_DIVIDER_ONE_BASED |
-- 
2.51.0