Re: [PATCH v3 11/19] soc: starfive: Add jh7110-hdmi-subsystem driver

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] Incorrect regmap configuration (.val_bits = 8) forces byte-wise accesses on a 32-bit register file, which may cause bus faults or ignored writes.
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commit 83ac96938fc0f15d53cdae0501c6e430a17c1c1d
Author: Michal Wilczynski <m.wilczynski@samsung.com>
soc: starfive: Add jh7110-hdmi-subsystem driver

This commit introduces a parent driver for the monolithic StarFive JH7110
HDMI IP block. It maps the shared register block and creates child devices
for the PHY and controller using a shared regmap.

> diff --git a/drivers/soc/starfive/jh7110-hdmi-subsystem.c b/drivers/soc/starfive/jh7110-hdmi-subsystem.c
> new file mode 100644
> index 0000000000000..e05b91825be4d
> --- /dev/null
> +++ b/drivers/soc/starfive/jh7110-hdmi-subsystem.c
[ ... ]
> +static const struct regmap_config starfive_hdmi_regmap_config = {
> +	.reg_bits = 32,
> +	.val_bits = 8,

[Severity: High]
Will this regmap configuration cause byte-wise memory accesses on a 32-bit
register file? 

Setting .val_bits = 8 forces the regmap core to use 8-bit readb()/writeb()
accesses instead of 32-bit readl()/writel(). The underlying Innosilicon
HDMI IP has registers spaced by 4 bytes and natively expects 32-bit
accesses.

On RISC-V platforms like the JH7110, byte-wise access to 32-bit APB
peripherals typically triggers a Store/Load Access Fault or results in
silently ignored writes.

> +	.max_register = 0x3fff,
> +};

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Sashiko AI review · https://sashiko.dev/#/patchset/20260904-jh7110-clean-send-v3-0-484f9ae72715@samsung.com?part=11