Re: [PATCH 06/17] soc: ti: pruss: Add a platform driver for PRUSS in TI SoCs

[David Lechner <david@lechnology.com>]

On 11/22/18 5:39 AM, Roger Quadros wrote:
> From: Suman Anna <s-anna@ti.com>
> 
> The PRUSS platform driver deals with the overall PRUSS and is
> used for managing the subsystem level resources like various
> memories. It is responsible for the creation and deletion of
> the platform devices for the child PRU devices and other child
> devices (Interrupt Controller or MDIO node or some syscon nodes)
> so that they can be managed by specific platform drivers.
> 
> This design provides flexibility in representing the different
> modules of PRUSS accordingly, and at the same time allowing the
> PRUSS driver to add some instance specific configuration within
> an SoC.
> 
> The driver currently supports the AM335x SoC.
> 
> Signed-off-by: Suman Anna <s-anna@ti.com>
> Signed-off-by: Andrew F. Davis <afd@ti.com>
> Signed-off-by: Roger Quadros <rogerq@ti.com>
> ---
>   drivers/soc/ti/Makefile |   2 +-
>   drivers/soc/ti/pruss.c  | 116 ++++++++++++++++++++++++++++++++++++++++++++++++
>   drivers/soc/ti/pruss.h  |  44 ++++++++++++++++++
>   3 files changed, 161 insertions(+), 1 deletion(-)
>   create mode 100644 drivers/soc/ti/pruss.c
>   create mode 100644 drivers/soc/ti/pruss.h
> 

...

> diff --git a/drivers/soc/ti/pruss.c b/drivers/soc/ti/pruss.c
> new file mode 100644
> index 0000000..0840b59
> --- /dev/null
> +++ b/drivers/soc/ti/pruss.c
> @@ -0,0 +1,116 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * PRU-ICSS platform driver for various TI SoCs
> + *
> + * Copyright (C) 2014-2018 Texas Instruments Incorporated - http://www.ti.com/
> + *	Suman Anna <s-anna@ti.com>
> + *	Andrew F. Davis <afd@ti.com>
> + */
> +
> +#include <linux/dma-mapping.h>
> +#include <linux/module.h>

alphabetical order?

> +#include <linux/io.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +
> +#include "pruss.h"
> +
> +static int pruss_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct device_node *node = dev->of_node;
> +	struct device_node *np;
> +	struct pruss *pruss;
> +	struct resource res;
> +	int ret, i, index;
> +	const char *mem_names[PRUSS_MEM_MAX] = { "dram0", "dram1", "shrdram2" };
> +
> +	if (!node) {
> +		dev_err(dev, "Non-DT platform device not supported\n");
> +		return -ENODEV;
> +	}
> +
> +	ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
> +	if (ret) {
> +		dev_err(dev, "dma_set_coherent_mask: %d\n", ret);
> +		return ret;
> +	}
> +
> +	pruss = devm_kzalloc(dev, sizeof(*pruss), GFP_KERNEL);
> +	if (!pruss)
> +		return -ENOMEM;
> +
> +	pruss->dev = dev;
> +
> +	np = of_get_child_by_name(node, "memories");
> +	if (!np)

error message?

> +		return -ENODEV;
> +
> +	for (i = 0; i < ARRAY_SIZE(mem_names); i++) {
> +		index = of_property_match_string(np, "reg-names", mem_names[i]);
> +		if (index < 0) {
> +			of_node_put(np);
> +			return index;
> +		}
> +
> +		if (of_address_to_resource(np, index, &res)) {
> +			of_node_put(np);
> +			return -EINVAL;
> +		}
> +
> +		pruss->mem_regions[i].va = devm_ioremap(dev, res.start,
> +							resource_size(&res));
> +		if (!pruss->mem_regions[i].va) {
> +			dev_err(dev, "failed to parse and map memory resource %d %s\n",
> +				i, mem_names[i]);
> +			of_node_put(np);
> +			return -ENOMEM;
> +		}
> +		pruss->mem_regions[i].pa = res.start;
> +		pruss->mem_regions[i].size = resource_size(&res);
> +
> +		dev_dbg(dev, "memory %8s: pa %pa size 0x%zx va %p\n",
> +			mem_names[i], &pruss->mem_regions[i].pa,
> +			pruss->mem_regions[i].size, pruss->mem_regions[i].va);
> +	}
> +	of_node_put(np);
> +
> +	platform_set_drvdata(pdev, pruss);
> +
> +	dev_info(&pdev->dev, "creating PRU cores and other child platform devices\n");

Is this really needed? Or dev_dbg instead?

> +	ret = of_platform_populate(node, NULL, NULL, &pdev->dev);
> +	if (ret)
> +		dev_err(dev, "of_platform_populate failed\n");
> +
> +	return ret;
> +}
> +
> +static int pruss_remove(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +
> +	dev_info(dev, "remove PRU cores and other child platform devices\n");

same here... looks like debug message

> +	of_platform_depopulate(dev);
> +
> +	return 0;
> +}
> +