2017-12-14 01:16:04

by Bjorn Andersson

[permalink] [raw]
Subject: Re: [PATCH v2 07/16] remoteproc: st: add reserved memory support

On Thu 30 Nov 08:46 PST 2017, Loic Pallardy wrote:

> ST remote processor needs some specified memory regions for firmware and IPC.
> Memory regions are defined as reserved memory and should be registered in
> remoteproc core thanks to rproc_add_carveout function.
> Memory region release is handled by ST driver itself on remove operation.
>
> Signed-off-by: Loic Pallardy <[email protected]>
> ---
> drivers/remoteproc/st_remoteproc.c | 43 +++++++++++++++++++++++++++++++-------
> 1 file changed, 35 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/remoteproc/st_remoteproc.c b/drivers/remoteproc/st_remoteproc.c
> index aacef0e..1549ce8 100644
> --- a/drivers/remoteproc/st_remoteproc.c
> +++ b/drivers/remoteproc/st_remoteproc.c
> @@ -19,6 +19,7 @@
> #include <linux/mfd/syscon.h>
> #include <linux/module.h>
> #include <linux/of.h>
> +#include <linux/of_address.h>
> #include <linux/of_device.h>
> #include <linux/of_reserved_mem.h>
> #include <linux/platform_device.h>
> @@ -208,8 +209,10 @@ static int st_rproc_parse_dt(struct platform_device *pdev)
> struct device *dev = &pdev->dev;
> struct rproc *rproc = platform_get_drvdata(pdev);
> struct st_rproc *ddata = rproc->priv;
> - struct device_node *np = dev->of_node;
> - int err;
> + struct device_node *node, *np = dev->of_node;
> + struct resource res;
> + struct rproc_mem_entry *mem;
> + int err, count, i;
>
> if (ddata->config->sw_reset) {
> ddata->sw_reset = devm_reset_control_get_exclusive(dev,
> @@ -254,10 +257,36 @@ static int st_rproc_parse_dt(struct platform_device *pdev)
> return -EINVAL;
> }
>
> - err = of_reserved_mem_device_init(dev);
> - if (err) {
> - dev_err(dev, "Failed to obtain shared memory\n");
> - return err;
> + count = of_count_phandle_with_args(np, "memory-region", NULL);
> +
> + for (i = 0; i < count; i++) {

If you use of_phandle_iterator this becomes a little bit more compact
and using of_reserved_mem_lookup() gives you the flexibility of
specifying the reserved-memory using size= in addition to a reg=.

of_phandle_iterator_init(&it, np, "memory-region", NULL, 0);
while ((err = of_phandle_iterator_next(&it)) == 0) {
rmem = of_reserved_mem_lookup(it->node);

// Memory is rmem->base, rmem->size;
}

> + node = of_parse_phandle(np, "memory-region", i);
> + if (!node) {
> + dev_err(dev, "No memory-region specified\n");
> + return -EINVAL;
> + }
> +
> + err = of_address_to_resource(node, 0, &res);
> + if (err) {
> + dev_err(dev, "Bad memory-region definition\n");
> + return err;
> + }
> +
> + mem = devm_kzalloc(dev, sizeof(*mem), GFP_KERNEL);
> + if (!mem)
> + return -ENOMEM;
> +
> + mem->dma = res.start;
> + mem->da = res.start;
> + mem->len = resource_size(&res);
> + mem->va = devm_ioremap_wc(dev, mem->dma, mem->len);
> + if (!mem->va) {
> + dev_err(dev, "Unable to map memory region: %pa+%zx\n",
> + &res.start, mem->len);
> + return -EBUSY;
> + }
> +
> + rproc_add_carveout(rproc, mem);
> }

We have a few copies of this logic, how about we move this into a helper
function in the core?

Regards,
Bjorn


2018-01-12 08:19:19

by Loic Pallardy

[permalink] [raw]
Subject: RE: [PATCH v2 07/16] remoteproc: st: add reserved memory support



> -----Original Message-----
> From: Bjorn Andersson [mailto:[email protected]]
> Sent: Thursday, December 14, 2017 2:16 AM
> To: Loic PALLARDY <[email protected]>
> Cc: [email protected]; [email protected]; linux-
> [email protected]; Arnaud POULIQUEN <[email protected]>;
> [email protected]
> Subject: Re: [PATCH v2 07/16] remoteproc: st: add reserved memory support
>
> On Thu 30 Nov 08:46 PST 2017, Loic Pallardy wrote:
>
> > ST remote processor needs some specified memory regions for firmware
> and IPC.
> > Memory regions are defined as reserved memory and should be registered
> in
> > remoteproc core thanks to rproc_add_carveout function.
> > Memory region release is handled by ST driver itself on remove operation.
> >
> > Signed-off-by: Loic Pallardy <[email protected]>
> > ---
> > drivers/remoteproc/st_remoteproc.c | 43
> +++++++++++++++++++++++++++++++-------
> > 1 file changed, 35 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/remoteproc/st_remoteproc.c
> b/drivers/remoteproc/st_remoteproc.c
> > index aacef0e..1549ce8 100644
> > --- a/drivers/remoteproc/st_remoteproc.c
> > +++ b/drivers/remoteproc/st_remoteproc.c
> > @@ -19,6 +19,7 @@
> > #include <linux/mfd/syscon.h>
> > #include <linux/module.h>
> > #include <linux/of.h>
> > +#include <linux/of_address.h>
> > #include <linux/of_device.h>
> > #include <linux/of_reserved_mem.h>
> > #include <linux/platform_device.h>
> > @@ -208,8 +209,10 @@ static int st_rproc_parse_dt(struct
> platform_device *pdev)
> > struct device *dev = &pdev->dev;
> > struct rproc *rproc = platform_get_drvdata(pdev);
> > struct st_rproc *ddata = rproc->priv;
> > - struct device_node *np = dev->of_node;
> > - int err;
> > + struct device_node *node, *np = dev->of_node;
> > + struct resource res;
> > + struct rproc_mem_entry *mem;
> > + int err, count, i;
> >
> > if (ddata->config->sw_reset) {
> > ddata->sw_reset = devm_reset_control_get_exclusive(dev,
> > @@ -254,10 +257,36 @@ static int st_rproc_parse_dt(struct
> platform_device *pdev)
> > return -EINVAL;
> > }
> >
> > - err = of_reserved_mem_device_init(dev);
> > - if (err) {
> > - dev_err(dev, "Failed to obtain shared memory\n");
> > - return err;
> > + count = of_count_phandle_with_args(np, "memory-region", NULL);
> > +
> > + for (i = 0; i < count; i++) {
>
> If you use of_phandle_iterator this becomes a little bit more compact
> and using of_reserved_mem_lookup() gives you the flexibility of
> specifying the reserved-memory using size= in addition to a reg=.
>
> of_phandle_iterator_init(&it, np, "memory-region", NULL, 0);
> while ((err = of_phandle_iterator_next(&it)) == 0) {
> rmem = of_reserved_mem_lookup(it->node);
>
> // Memory is rmem->base, rmem->size;
> }
>

Good point, thanks

> > + node = of_parse_phandle(np, "memory-region", i);
> > + if (!node) {
> > + dev_err(dev, "No memory-region specified\n");
> > + return -EINVAL;
> > + }
> > +
> > + err = of_address_to_resource(node, 0, &res);
> > + if (err) {
> > + dev_err(dev, "Bad memory-region definition\n");
> > + return err;
> > + }
> > +
> > + mem = devm_kzalloc(dev, sizeof(*mem), GFP_KERNEL);
> > + if (!mem)
> > + return -ENOMEM;
> > +
> > + mem->dma = res.start;
> > + mem->da = res.start;
> > + mem->len = resource_size(&res);
> > + mem->va = devm_ioremap_wc(dev, mem->dma, mem-
> >len);
> > + if (!mem->va) {
> > + dev_err(dev, "Unable to map memory region:
> %pa+%zx\n",
> > + &res.start, mem->len);
> > + return -EBUSY;
> > + }
> > +
> > + rproc_add_carveout(rproc, mem);
> > }
>
> We have a few copies of this logic, how about we move this into a helper
> function in the core?
>
Yes, helper function to abstract rproc_mem_entry structure would be nice

Regards,
Loic

> Regards,
> Bjorn