Re: [PATCH v4 08/16] spi: cadence-quadspi: add PHY tuning support

[Mark Brown]

On Thu, Jun 18, 2026 at 01:07:17PM +0530, Santhosh Kumar K wrote:
> The Cadence QSPI controller supports a delay-line PHY for high-speed
> operation. Without calibration the PHY is unused and read capture relies
> on a fixed delay, limiting throughput at frequencies above the base
> operating speed.

> +static int cqspi_get_phy_pattern_offset(struct device *dev, u32 *offset)
> +{
> +	struct device_node *np, *flash_np = NULL, *part_np;
> +	const __be32 *reg;
> +	int len;
> +
> +	if (!dev || !dev->of_node)
> +		return -EINVAL;
> +
> +	for_each_child_of_node(dev->of_node, np) {
> +		if (of_node_name_prefix(np, "flash")) {
> +			flash_np = np;
> +			break;
> +		}
> +	}

This isn't going to do the right thing if there's more than one flash,
that doesn't seem a super sensible hardware configuration but I'm not
sure I see anything stopping it being set up and system integrators do
enjoy differentiating.

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