Re: [PATCH v4 7/8] remoteproc: da8xx: use the reset framework

Suman Anna
2018-03-26T21:29:56Z

Hi Bart,

On 03/23/2018 08:04 AM, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
>
> Switch to using the reset framework instead of handcoded reset routines
> we used so far.
>
> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> ---
> drivers/remoteproc/da8xx_remoteproc.c | 32 +++++++++++++++++++++++++++-----
> 1 file changed, 27 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/remoteproc/da8xx_remoteproc.c b/drivers/remoteproc/da8xx_remoteproc.c
> index f134192922e0..3689473f8b49 100644
> --- a/drivers/remoteproc/da8xx_remoteproc.c
> +++ b/drivers/remoteproc/da8xx_remoteproc.c
> @@ -10,6 +10,7 @@
>
> #include <linux/bitops.h>
> #include <linux/clk.h>
> +#include <linux/reset.h>
> #include <linux/err.h>
> #include <linux/interrupt.h>
> #include <linux/io.h>
> @@ -20,8 +21,6 @@
> #include <linux/platform_device.h>
> #include <linux/remoteproc.h>
>
> -#include <mach/clock.h> /* for davinci_clk_reset_assert/deassert() */
> -
> #include "remoteproc_internal.h"
>
> static char *da8xx_fw_name;
> @@ -72,6 +71,7 @@ struct da8xx_rproc {
> struct da8xx_rproc_mem *mem;
> int num_mems;
> struct clk *dsp_clk;
> + struct reset_control *dsp_reset;
> void (*ack_fxn)(struct irq_data *data);
> struct irq_data *irq_data;
> void __iomem *chipsig;
> @@ -138,6 +138,7 @@ static int da8xx_rproc_start(struct rproc *rproc)
> struct device *dev = rproc->dev.parent;
> struct da8xx_rproc *drproc = (struct da8xx_rproc *)rproc->priv;
> struct clk *dsp_clk = drproc->dsp_clk;
> + struct reset_control *dsp_reset = drproc->dsp_reset;
> int ret;
>
> /* hw requires the start (boot) address be on 1KB boundary */
> @@ -155,7 +156,11 @@ static int da8xx_rproc_start(struct rproc *rproc)
> return ret;
> }
>
> - davinci_clk_reset_deassert(dsp_clk);
> + ret = reset_control_deassert(dsp_reset);
> + if (ret) {
> + dev_err(dev, "reset_control_deassert() failed: %d\n", ret);
> + return ret;

need to unwind the clk_prepare_enable() here.

> + }
>
> return 0;
> }
> @@ -163,8 +168,15 @@ static int da8xx_rproc_start(struct rproc *rproc)
> static int da8xx_rproc_stop(struct rproc *rproc)
> {
> struct da8xx_rproc *drproc = rproc->priv;
> + int ret;
> +
> + ret = reset_control_assert(drproc->dsp_reset);
> + if (ret) {
> + dev_err(rproc->dev.parent,
> + "reset_control_assert() failed: %d\n", ret);

prefer the trace statement to be on the same line as dev_err, you can
just keep the ret on the next line. I am fine with defining a local dev
variable as well (mirrors da8xx_rproc_start() to have the trace in a
single line).

> + return ret;
> + }
>
> - davinci_clk_reset_assert(drproc->dsp_clk);
> clk_disable_unprepare(drproc->dsp_clk);
>
> return 0;
> @@ -232,6 +244,7 @@ static int da8xx_rproc_probe(struct platform_device *pdev)
> struct resource *bootreg_res;
> struct resource *chipsig_res;
> struct clk *dsp_clk;
> + struct reset_control *dsp_reset;
> void __iomem *chipsig;
> void __iomem *bootreg;
> int irq;
> @@ -268,6 +281,15 @@ static int da8xx_rproc_probe(struct platform_device *pdev)
> return PTR_ERR(dsp_clk);
> }
>
> + dsp_reset = devm_reset_control_get_exclusive(dev, NULL);
> + if (IS_ERR(dsp_reset)) {
> + if (PTR_ERR(dsp_reset) != -EPROBE_DEFER)
> + dev_err(dev, "unable to get reset control: %ld\n",
> + PTR_ERR(dsp_reset));
> +
> + return PTR_ERR(dsp_reset);
> + }
> +
> if (dev->of_node) {
> ret = of_reserved_mem_device_init(dev);
> if (ret) {
> @@ -309,7 +331,7 @@ static int da8xx_rproc_probe(struct platform_device *pdev)
> * *not* in reset, but da8xx_rproc_start() needs the DSP to be
> * held in reset at the time it is called.
> */
> - ret = davinci_clk_reset_assert(drproc->dsp_clk);
> + ret = reset_control_assert(dsp_reset);
> if (ret)
> goto free_rproc;
>

The reset API usage changes themselves look good otherwise.

regards
Suman