Re: [RFC PATCH 2/3] remoteproc: imx_rproc: add a NXP/Freescale imx rproc driver
From: Bjorn Andersson
Date: Sun Jun 25 2017 - 16:41:29 EST
On Wed 14 Jun 13:48 PDT 2017, Oleksij Rempel wrote:
> From: Oleksij Rempel <linux@xxxxxxxxxxxxxxxx>
>
> this driver was tested on NXP imx7d but should work on
> imx6sx as well.
> It will upload firmware to OCRAM, which shared memory between
> Cortex A7 and Cortex M4, then turn M4 on.
>
This looks very generic, are there any IMX specific parts or is this the
"default" way of integrating a M4? Could we perhaps come up with a
common M4-rproc driver?
Even though it will be rather short, you need a DT binding document
defining the compatible and the few properties that you use.
> Signed-off-by: Oleksij Rempel <linux@xxxxxxxxxxxxxxxx>
> ---
> drivers/remoteproc/Kconfig | 8 ++
> drivers/remoteproc/Makefile | 1 +
> drivers/remoteproc/imx_rproc.c | 264 +++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 273 insertions(+)
> create mode 100644 drivers/remoteproc/imx_rproc.c
>
> diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
> index faad69a1a597..8d33bff4f530 100644
> --- a/drivers/remoteproc/Kconfig
> +++ b/drivers/remoteproc/Kconfig
> @@ -130,6 +130,14 @@ config ST_SLIM_REMOTEPROC
> tristate
> depends on REMOTEPROC
>
> +config IMX_REMOTEPROC
Please make an attempt to keep entries in the Kconfig and Makefile
alphabetically sorted.
> + tristate "IMX6/7 remoteproc support"
> + depends on SOC_IMX6SX || SOC_IMX7D
> + depends on REMOTEPROC
> + help
> + TODO, write some thing here
> + This can be either built-in or a loadable module.
> +
> endif # REMOTEPROC
>
> endmenu
> diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
> index ffc5e430df27..d351c25cdb4e 100644
> --- a/drivers/remoteproc/Makefile
> +++ b/drivers/remoteproc/Makefile
> @@ -19,3 +19,4 @@ qcom_wcnss_pil-y += qcom_wcnss.o
> qcom_wcnss_pil-y += qcom_wcnss_iris.o
> obj-$(CONFIG_ST_REMOTEPROC) += st_remoteproc.o
> obj-$(CONFIG_ST_SLIM_REMOTEPROC) += st_slim_rproc.o
> +obj-$(CONFIG_IMX_REMOTEPROC) += imx_rproc.o
> diff --git a/drivers/remoteproc/imx_rproc.c b/drivers/remoteproc/imx_rproc.c
> new file mode 100644
> index 000000000000..6bef85237a27
> --- /dev/null
> +++ b/drivers/remoteproc/imx_rproc.c
> @@ -0,0 +1,264 @@
> +/*
> + * Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +#include <linux/remoteproc.h>
> +#include <linux/regmap.h>
> +#include <linux/mfd/syscon.h>
> +
> +#define IMX7D_ENABLE_M4 BIT(3)
> +#define IMX7D_SW_M4P_RST BIT(2)
> +#define IMX7D_SW_M4C_RST BIT(1)
> +#define IMX7D_SW_M4C_NON_SCLR_RST BIT(0)
> +
> +#define IMX7D_M4_RST_MASK 0xf
> +
> +
> +#define IMX7D_RPROC_MEM_MAX 2
> +enum {
> + IMX7D_RPROC_IMEM,
> + IMX7D_RPROC_DMEM,
> +};
> +
> +static const char *mem_names[IMX7D_RPROC_MEM_MAX] = {
> + [IMX7D_RPROC_IMEM] = "imem",
> + [IMX7D_RPROC_DMEM] = "dmem",
> +};
> +
> +/**
> + * struct imx_rproc_mem - slim internal memory structure
> + * @cpu_addr: MPU virtual address of the memory region
> + * @bus_addr: Bus address used to access the memory region
> + * @size: Size of the memory region
> + */
> +struct imx_rproc_mem {
> + void __iomem *cpu_addr;
> + phys_addr_t bus_addr;
> + size_t size;
> +};
> +
> +struct imx_rproc_dcfg {
> + int offset;
> +};
Unless you foresee this being expanded in the very near future I would
prefer that you just inline the offset in imx_rproc and put (void*)0xc
as .data in your of_match (typecast the of_device_get_match_data result
to unsigned long).
> +
> +struct imx_rproc {
> + struct device *dev;
> + struct regmap *regmap;
> + struct rproc *rproc;
> + const struct imx_rproc_dcfg *dcfg;
> + struct imx_rproc_mem mem[IMX7D_RPROC_MEM_MAX];
> + struct clk *clk;
> +};
> +
> +static const struct imx_rproc_dcfg imx_rproc_cfg_imx7d = {
> + .offset = 0xc,
> +};
> +
> +static int imx_rproc_start(struct rproc *rproc)
> +{
> + struct imx_rproc *priv = rproc->priv;
> + const struct imx_rproc_dcfg *dcfg = priv->dcfg;
> + struct device *dev = priv->dev;
> + int ret;
> +
> + ret = clk_enable(priv->clk);
> + if (ret) {
> + dev_err(&rproc->dev, "Failed to enable clock\n");
> + return ret;
> + }
> +
> + ret = regmap_update_bits(priv->regmap, dcfg->offset,
> + IMX7D_M4_RST_MASK,
> + IMX7D_SW_M4C_RST | IMX7D_SW_M4P_RST | IMX7D_ENABLE_M4);
> + if (ret) {
> + dev_err(dev, "Filed to enable M4!\n");
> + clk_disable(priv->clk);
> + }
> +
> + return ret;
> +}
> +
> +static int imx_rproc_stop(struct rproc *rproc)
> +{
> + struct imx_rproc *priv = rproc->priv;
> + const struct imx_rproc_dcfg *dcfg = priv->dcfg;
> + struct device *dev = priv->dev;
> + int ret;
> +
> + ret = regmap_update_bits(priv->regmap, dcfg->offset,
> + IMX7D_M4_RST_MASK,
> + IMX7D_SW_M4C_NON_SCLR_RST);
> + if (ret)
> + dev_err(dev, "Filed to stop M4!\n");
> +
> + clk_disable(priv->clk);
> +
> + return ret;
> +}
> +
> +static void *imx_rproc_da_to_va(struct rproc *rproc, u64 da, int len)
> +{
> + struct imx_rproc *priv = rproc->priv;
> + void *va = NULL;
> + int i;
> +
> + for (i = 0; i < IMX7D_RPROC_MEM_MAX; i++) {
> + if (da != priv->mem[i].bus_addr)
> + continue;
> +
> + if (len <= priv->mem[i].size) {
> + /* __force to make sparse happy with type conversion */
> + va = (__force void *)priv->mem[i].cpu_addr;
> + break;
> + }
> + }
> +
> + dev_dbg(&rproc->dev, "da = 0x%llx len = 0x%x va = 0x%p\n", da, len, va);
> +
> + return va;
> +}
> +
> +static const struct rproc_ops imx_rproc_ops = {
> + .start = imx_rproc_start,
> + .stop = imx_rproc_stop,
> + .da_to_va = imx_rproc_da_to_va,
> +};
> +
> +static const struct of_device_id imx_rproc_of_match[] = {
> + { .compatible = "fsl,imx7d-rproc", .data = &imx_rproc_cfg_imx7d },
.data = (void*)0xc
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, imx_rproc_of_match);
By using of_device_get_match_data() you don't need to reference your
of_device_id table, so please move it down to your definition of
imx_rproc_driver.
[..]
> +static int imx_rproc_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np = dev->of_node;
> + struct imx_rproc *priv;
> + struct rproc *rproc;
> + struct regmap_config config = { .name = "imx_rproc" };
> + const struct imx_rproc_dcfg *dcfg;
> + struct regmap *regmap;
> + int ret;
> +
> + regmap = syscon_regmap_lookup_by_phandle(np, "syscon");
> + if (IS_ERR(regmap)) {
> + dev_err(dev, "failed to find syscon\n");
> + return PTR_ERR(regmap);
> + }
> + regmap_attach_dev(dev, regmap, &config);
Indentation...
> +
> + /* set some other name then imx */
> + rproc = rproc_alloc(dev, "imx_rproc", &imx_rproc_ops, NULL, sizeof(*priv));
> + if (!rproc) {
> + ret = -ENOMEM;
> + goto err;
> + }
> +
> + dcfg = of_device_get_match_data(dev);
priv->cfg_offset = (unsigned long)of_device_get_match_data(dev);
> + if (!dcfg)
> + return -EINVAL;
> +
> + priv = rproc->priv;
> + priv->rproc = rproc;
> + priv->regmap = regmap;
> + priv->dcfg = dcfg;
> +
> + dev_set_drvdata(dev, rproc);
> +
> + ret = imx_rproc_addr_init(priv, pdev);
> + if (ret) {
> + dev_err(dev, "filed on imx_rproc_addr_init\n");
> + goto err_put_rproc;
> + }
> +
> + priv->clk = devm_clk_get(dev, NULL);
> + if (IS_ERR(priv->clk)) {
> + dev_err(dev, "Failed to get clock\n");
rproc_free()
> + return PTR_ERR(priv->clk);
> + }
> +
> + ret = rproc_add(rproc);
> + if (ret) {
> + dev_err(dev, "rproc_add failed\n");
> + goto err_put_rproc;
> + }
> +
> + ret = clk_prepare(priv->clk);
1) You're not unpreparing this clock in remove.
2) Why do you prepare the clock here instead of prepare_enable &
disable_unprepare it during start/stop?
3) This is racy as you could have start() being called between
rproc_add() and clk_prepare() (although highly unlikely...).
> + if (ret)
> + dev_err(dev, "failed to get clock\n");
s/get/prepare/
Regards,
Bjorn