[PATCH v4 6/9] pci: brcmstb: Get and use bridge and rescal reset properties

[Neil Armstrong]

On 5/23/26 18:34, Torsten Duwe wrote:
> From: Torsten Duwe <duwe at suse.de>
> 
> Check whether the device tree has nodes for the two reset controls and use
> them if so.
> 
> Signed-off-by: Torsten Duwe <duwe at suse.de>
> Co-authored-by: Oleksii Moisieiev <oleksii_moisieiev at epam.com>
> Tested-by: Pedro Falcato <pfalcato at suse.de>
> ---
>   drivers/pci/pcie_brcmstb.c | 70 +++++++++++++++++++++++++++++++++++---
>   1 file changed, 65 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/pci/pcie_brcmstb.c b/drivers/pci/pcie_brcmstb.c
> index 5cb39dfd136..4d253440de9 100644
> --- a/drivers/pci/pcie_brcmstb.c
> +++ b/drivers/pci/pcie_brcmstb.c
> @@ -21,6 +21,7 @@
>   #include <linux/bitfield.h>
>   #include <linux/log2.h>
>   #include <linux/iopoll.h>
> +#include <reset.h>
>   
>   /* PCIe parameters */
>   #define BRCM_NUM_PCIE_OUT_WINS				4
> @@ -79,6 +80,8 @@ struct brcm_pcie {
>   
>   	int			gen;
>   	bool			ssc;
> +	struct reset_ctl	rescal;
> +	struct reset_ctl	bridge_reset;
>   	const struct brcm_pcie_cfg_data *pcie_cfg;
>   };
>   
> @@ -143,14 +146,57 @@ static void brcm_pcie_perst_set_2712(struct brcm_pcie *pcie, u32 val)
>   	writel(tmp, pcie->base + PCIE_MISC_PCIE_CTRL);
>   }
>   
> -static void brcm_pcie_bridge_sw_init_set(struct brcm_pcie *pcie, u32 val)
> +static int brcm_pcie_get_resets_dt(struct udevice *dev)
>   {
> +	struct brcm_pcie *pcie = dev_get_priv(dev);
> +	int ret;
> +
> +	ret = reset_get_by_name(dev, "rescal", &pcie->rescal);
> +	if (ret) {
> +		printf("Unable to get rescal reset\n");
> +		return ret;
> +	}
> +
> +	ret = reset_get_by_name(dev, "bridge", &pcie->bridge_reset);
> +	if (ret) {
> +		printf("Unable to get bridge reset\n");
> +	}

Drop the {}

> +	return ret;
> +}
> +
> +static int brcm_pcie_do_reset(struct udevice *dev)
> +{
> +	struct brcm_pcie *pcie = dev_get_priv(dev);
> +	int ret;
> +
> +	ret = reset_deassert(&pcie->rescal);
> +	if (ret)
> +		printf("failed to deassert 'rescal'\n");
> +	return ret;
> +}
> +
> +static int brcm_pcie_bridge_sw_init_set(struct brcm_pcie *pcie, u32 val)
> +{
> +	int ret = 0;
> +
> +	if (pcie->bridge_reset.dev)

You could use reset_valid() instead

> +	{
> +		if (val)
> +			ret = reset_assert(&pcie->bridge_reset);
> +		else
> +			ret = reset_deassert(&pcie->bridge_reset);
> +		if (ret)
> +			log_err("failed to %sassert bridge reset, err=%d\n",
> +				val ? "" : "de", ret);
> +		return ret;
> +	}


Add an empty line here

>   	if (val)
>   		setbits_le32(pcie->base + pcie->pcie_cfg->offsets[RGR1_SW_INIT_1],
>   			     RGR1_SW_INIT_1_INIT_MASK);
>   	else
>   		clrbits_le32(pcie->base + pcie->pcie_cfg->offsets[RGR1_SW_INIT_1],
>   			     RGR1_SW_INIT_1_INIT_MASK);
> +	return ret;

Just return 0 instead

>   }
>   
>   /**
> @@ -405,16 +451,25 @@ static int brcm_pcie_probe(struct udevice *dev)
>   	int num_out_wins = 0;
>   	u64 rc_bar2_offset, rc_bar2_size;
>   	unsigned int scb_size_val;
> -	int i, ret;
> +	int i, ret = 0;
>   	u16 nlw, cls, lnksta;
>   	u32 tmp;
>   
> +	/*
> +	 * Ensure rescal reset for BCM2712 is really disabled.
> +	 */
> +	if (pcie->pcie_cfg->type == BCM2712)
> +		ret = brcm_pcie_do_reset(dev);
> +	if (ret)
> +		return ret;
>   	/*
>   	 * Reset the bridge, assert the fundamental reset. Note for some SoCs,
>   	 * e.g. BCM7278, the fundamental reset should not be asserted here.
>   	 * This will need to be changed when support for other SoCs is added.
>   	 */
> -	brcm_pcie_bridge_sw_init_set(pcie, 1);
> +	ret = brcm_pcie_bridge_sw_init_set(pcie, 1);
> +	if (ret)
> +		return ret;
>   	if (pcie->pcie_cfg->type != BCM2712)
>   		pcie->pcie_cfg->perst_set(pcie, 1);
>   	/*
> @@ -424,8 +479,9 @@ static int brcm_pcie_probe(struct udevice *dev)
>   	udelay(100);
>   
>   	/* Take the bridge out of reset */
> -	brcm_pcie_bridge_sw_init_set(pcie, 0);
> -
> +	ret = brcm_pcie_bridge_sw_init_set(pcie, 0);
> +	if (ret)
> +		return ret;
>   	clrbits_le32(base + pcie->pcie_cfg->offsets[PCIE_HARD_DEBUG],
>   		     PCIE_HARD_DEBUG_SERDES_IDDQ_MASK);
>   
> @@ -607,6 +663,10 @@ static int brcm_pcie_of_to_plat(struct udevice *dev)
>   		pcie->gen = max_link_speed;
>   
>   	pcie->pcie_cfg = (const struct brcm_pcie_cfg_data *)dev_get_driver_data(dev);
> +
> +	if (pcie->pcie_cfg->type == BCM2712)
> +		return brcm_pcie_get_resets_dt(dev);
> +
>   	return 0;
>   }
>   

With those changes:
Reviewed-by: Neil Armstrong <neil.armstrong at linaro.org>

Thanks,
Neil