Re: [Patch v5 1/4] memory: tegra: Add memory controller channels support

[Dmitry Osipenko <digetx@gmail.com>]

16.03.2022 12:25, Ashish Mhetre пишет:
> From tegra186 onwards, memory controller support multiple channels.
> Add support for mapping address spaces of these channels.
> Make sure that number of channels are as expected on each SOC.
> During error interrupts from memory controller, appropriate registers
> from these channels need to be accessed for logging error info.
> 
> Signed-off-by: Ashish Mhetre <amhetre@nvidia.com>
> ---
>  drivers/memory/tegra/mc.c       |  6 ++++
>  drivers/memory/tegra/tegra186.c | 52 +++++++++++++++++++++++++++++++++
>  drivers/memory/tegra/tegra194.c |  1 +
>  drivers/memory/tegra/tegra234.c |  1 +
>  include/soc/tegra/mc.h          |  7 +++++
>  5 files changed, 67 insertions(+)
> 
> diff --git a/drivers/memory/tegra/mc.c b/drivers/memory/tegra/mc.c
> index bf3abb6d8354..3cda1d9ad32a 100644
> --- a/drivers/memory/tegra/mc.c
> +++ b/drivers/memory/tegra/mc.c
> @@ -749,6 +749,12 @@ static int tegra_mc_probe(struct platform_device *pdev)
>  	if (IS_ERR(mc->regs))
>  		return PTR_ERR(mc->regs);
>  
> +	if (mc->soc->ops && mc->soc->ops->map_regs) {
> +		err = mc->soc->ops->map_regs(mc, pdev);
> +		if (err < 0)
> +			return err;
> +	}
> +
>  	mc->debugfs.root = debugfs_create_dir("mc", NULL);
>  
>  	if (mc->soc->ops && mc->soc->ops->probe) {
> diff --git a/drivers/memory/tegra/tegra186.c b/drivers/memory/tegra/tegra186.c
> index 3d153881abc1..a8a45e6ff1f1 100644
> --- a/drivers/memory/tegra/tegra186.c
> +++ b/drivers/memory/tegra/tegra186.c
> @@ -139,11 +139,62 @@ static int tegra186_mc_probe_device(struct tegra_mc *mc, struct device *dev)
>  	return 0;
>  }
>  
> +static int tegra186_mc_map_regs(struct tegra_mc *mc,
> +				struct platform_device *pdev)
> +{
> +	struct device_node *np = pdev->dev.parent->of_node;
> +	int num_dt_channels, reg_cells = 0;
> +	struct resource *res;
> +	int i, ret;
> +	u32 val;
> +
> +	ret = of_property_read_u32(np, "#address-cells", &val);
> +	if (ret) {
> +		dev_err(&pdev->dev, "missing #address-cells property\n");
> +		return ret;
> +	}
> +
> +	reg_cells = val;
> +
> +	ret = of_property_read_u32(np, "#size-cells", &val);
> +	if (ret) {
> +		dev_err(&pdev->dev, "missing #size-cells property\n");
> +		return ret;
> +	}
> +
> +	reg_cells += val;
> +
> +	num_dt_channels = of_property_count_elems_of_size(pdev->dev.of_node, "reg",
> +							  reg_cells * sizeof(u32));
> +	/*
> +	 * On tegra186 onwards, memory controller support multiple channels.
> +	 * Apart from regular memory controller channels, there is one broadcast
> +	 * channel and one for stream-id registers.
> +	 */
> +	if (num_dt_channels < mc->soc->num_channels + 2) {
> +		dev_warn(&pdev->dev, "MC channels are missing, please update\n");

Update what?

> +		return 0;
> +	}
> +
> +	mc->mcb_regs = devm_platform_get_and_ioremap_resource(pdev, 1, &res);

Can't we name each reg bank individually in the DT and then use
devm_platform_ioremap_resource_byname()?

...
> @@ -212,6 +217,8 @@ struct tegra_mc {
>  	struct tegra_smmu *smmu;
>  	struct gart_device *gart;
>  	void __iomem *regs;
> +	void __iomem *mcb_regs;
> +	void __iomem *mc_regs[MC_MAX_CHANNELS];

s/mc_regs/ch_regs/ ?