[PATCH v3 11/12] mmc: Introduce mmc_phys_to_bus()/mmc_bus_to_phys()

[Nicolas Saenz Julienne]

On Mon, 2020-12-21 at 09:47 -0700, Simon Glass wrote:
> Hi Nicolas,
> 
> On Mon, 21 Dec 2020 at 07:23, Nicolas Saenz Julienne
> <nsaenzjulienne at suse.de> wrote:
> > 
> > On Fri, 2020-12-18 at 19:28 -0700, Simon Glass wrote:
> > > On Tue, 15 Dec 2020 at 10:23, Nicolas Saenz Julienne
> > > <nsaenzjulienne at suse.de> wrote:
> > > > 
> > > > This will allow us to use DM variants of phys_to_bus()/bus_to_phys()
> > > > when relevant.
> > > > 
> > > > Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne at suse.de>
> > > > ---
> > > >  drivers/mmc/sdhci.c |  7 ++++---
> > > >  include/mmc.h       | 10 ++++++++++
> > > >  2 files changed, 14 insertions(+), 3 deletions(-)
> > > 
> > > Reviewed-by: Simon Glass <sjg at chromium.org>
> > > 
> > > 
> > > > 
> > > > diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
> > > > index 0628934312..2086d7cdb1 100644
> > > > --- a/drivers/mmc/sdhci.c
> > > > +++ b/drivers/mmc/sdhci.c
> > > > @@ -19,7 +19,6 @@
> > > >  #include <linux/bitops.h>
> > > >  #include <linux/delay.h>
> > > >  #include <linux/dma-mapping.h>
> > > > -#include <phys2bus.h>
> > > > 
> > > >  static void sdhci_reset(struct sdhci_host *host, u8 mask)
> > > >  {
> > > > @@ -103,7 +102,8 @@ static void sdhci_prepare_dma(struct sdhci_host *host, struct mmc_data *data,
> > > >                                           mmc_get_dma_dir(data));
> > > > 
> > > >         if (host->flags & USE_SDMA) {
> > > > -               sdhci_writel(host, phys_to_bus((ulong)host->start_addr),
> > > > +               sdhci_writel(host,
> > > > +                            mmc_phys_to_bus(host->mmc, (ulong)host->start_addr),
> > > >                                 SDHCI_DMA_ADDRESS);
> > > >         }
> > > >  #if CONFIG_IS_ENABLED(MMC_SDHCI_ADMA)
> > > > @@ -162,7 +162,8 @@ static int sdhci_transfer_data(struct sdhci_host *host, struct mmc_data *data)
> > > >                                 start_addr &=
> > > >                                 ~(SDHCI_DEFAULT_BOUNDARY_SIZE - 1);
> > > >                                 start_addr += SDHCI_DEFAULT_BOUNDARY_SIZE;
> > > > -                               sdhci_writel(host, phys_to_bus((ulong)start_addr),
> > > > +                               sdhci_writel(host,
> > > > +                                            mmc_phys_to_bus(host->mmc, (ulong)start_addr),
> > > >                                              SDHCI_DMA_ADDRESS);
> > > >                         }
> > > >                 }
> > > > diff --git a/include/mmc.h b/include/mmc.h
> > > > index 1d377e0281..5fe1ef1dfc 100644
> > > > --- a/include/mmc.h
> > > > +++ b/include/mmc.h
> > > > @@ -15,6 +15,7 @@
> > > >  #include <linux/compiler.h>
> > > >  #include <linux/dma-direction.h>
> > > >  #include <part.h>
> > > > +#include <phys2bus.h>
> > > > 
> > > >  struct bd_info;
> > > > 
> > > > @@ -977,4 +978,13 @@ static inline enum dma_data_direction mmc_get_dma_dir(struct mmc_data *data)
> > > >         return data->flags & MMC_DATA_WRITE ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
> > > >  }
> > > > 
> > > > +static inline dma_addr_t mmc_phys_to_bus(struct mmc *mmc, phys_addr_t addr)
> > > > +{
> > > > +#if CONFIG_IS_ENABLED(DM_DMA)
> > > 
> > > if() ?
> > 
> > Noted.
> > 
> > > Also makes me wonder if dev_phys_to_bus() should call phys_to_bus() if
> > > DM_DMA is not enabled?
> > 
> > I'd still need some sort per-subsystem macro to cater for !DM configurations
> > where the device pointer isn't defined in the controller struct. Which IMO
> > isn't much of an enhancement to this approach.
> 
> We don't need to worry about non-DM for new features. In fact we don't
> generally accept code that adds new features to non-DM code. It is
> deprecated and slated for removal, so it just prolongs the migration.

Understood, so let's not call the plain phys_to_bus() and assume a 1:1 address
translation on non DM_DMA users (for both mmc and xhci). I'd say it's pretty
safe to do anyway, as it seems phys2bus.h was introduced specially for the RPi
family.

There still are some rogue users of the non dev dependent phys_to_bus() API in
RPi platform code. I'll try to clean that up in a subsequent series.

Regards,
Nicolas

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: This is a digitally signed message part
URL: <https://lists.denx.de/pipermail/u-boot/attachments/20201221/e1d87d8d/attachment.sig>