Re: [RFC 2/5] WIP: MIPS: implement dma mapping functions

[Antony Pavlov <antonynpavlov@gmail.com>]

On Mon, 13 Jan 2020 09:26:36 +0100
Oleksij Rempel <o.rempel@pengutronix.de> wrote:

> On 09.01.20 08:28, Antony Pavlov wrote:
> > TODO: fix warnings
> > 
> > arch/mips/include/asm/dma-mapping.h: In function ‘dma_free_coherent’:
> > arch/mips/include/asm/dma-mapping.h:31:21: warning: passing argument 1 of ‘phys_to_virt’
> > makes integer from pointer without a cast [-Wint-conversion]
> >     free(phys_to_virt(vaddr));
> >                       ^~~~~
> > In file included from include/common.h:33:0,
> >                   from drivers/net/e1000/main.c:32:
> > arch/mips/include/asm/io.h:40:21: note: expected ‘long unsigned int’ but argument is of type ‘void *’
> >   static inline void *phys_to_virt(unsigned long address)
> >                       ^~~~~~~~~~~~
> > 
> > Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
> > Signed-off-by: Peter Mamonov <pmamonov@gmail.com>
> > ---
> >   arch/mips/include/asm/dma-mapping.h |  2 +-
> >   arch/mips/lib/dma-default.c         | 22 ++++++++++++++++++++--
> >   2 files changed, 21 insertions(+), 3 deletions(-)
> > 
> > diff --git a/arch/mips/include/asm/dma-mapping.h b/arch/mips/include/asm/dma-mapping.h
> > index c71a087038..5013e7b369 100644
> > --- a/arch/mips/include/asm/dma-mapping.h
> > +++ b/arch/mips/include/asm/dma-mapping.h
> > @@ -28,7 +28,7 @@ static inline void dma_free_coherent(void *vaddr, dma_addr_t dma_handle,
> >   				     size_t size)
> >   {
> >   	if (IS_ENABLED(CONFIG_MMU))
> > -		free((void *)CKSEG0ADDR(vaddr));
> > +		free(phys_to_virt(vaddr));
> >   	else
> >   		free(vaddr);
> >   }
> > diff --git a/arch/mips/lib/dma-default.c b/arch/mips/lib/dma-default.c
> > index fbe627c24c..40caf6f91b 100644
> > --- a/arch/mips/lib/dma-default.c
> > +++ b/arch/mips/lib/dma-default.c
> > @@ -8,9 +8,11 @@
> >   
> >   #if defined(CONFIG_CPU_MIPS32) || \
> >   	defined(CONFIG_CPU_MIPS64)
> > -static inline void __dma_sync_mips(unsigned long addr, size_t size,
> > +static inline void __dma_sync_mips(dma_addr_t _addr, size_t size,
> >   				   enum dma_data_direction direction)
> >   {
> > +	void *addr = phys_to_virt(_addr);
> > +
> >   	switch (direction) {
> >   	case DMA_TO_DEVICE:
> >   		dma_flush_range(addr, addr + size);
> > @@ -29,7 +31,7 @@ static inline void __dma_sync_mips(unsigned long addr, size_t size,
> >   	}
> >   }
> >   #else
> > -static inline void __dma_sync_mips(void *addr, size_t size,
> > +static inline void __dma_sync_mips(dma_addr_t addr, size_t size,
> >   	enum dma_data_direction direction)
> >   {
> >   }
> > @@ -46,3 +48,19 @@ void dma_sync_single_for_device(dma_addr_t address, size_t size,
> >   {
> >   	__dma_sync_mips(address, size, dir);
> >   }
> > +
> > +dma_addr_t dma_map_single(struct device_d *dev, void *ptr, size_t size,
> > +			  enum dma_data_direction dir)
> > +{
> > +	unsigned long addr = virt_to_phys(ptr);
> > +
> > +	dma_sync_single_for_device(addr, size, dir);
> 
> Hm.. i was thinking Hit Invalidate D instruction works with Virtual addresses. Are you 
> sure we need to use virt_to_phys() here?

dma_sync_single_for_device() is a barebox-wide function (see include/dma.h).
The dma_sync_single_for_device() 1st argument type is dma_addr_t (physical address).
So virt_to_phys() conversion is necessary here.
 
> > +
> > +	return addr;
> > +}
> > +
> > +void dma_unmap_single(struct device_d *dev, dma_addr_t addr, size_t size,
> > +		      enum dma_data_direction dir)
> > +{
> > +	dma_sync_single_for_cpu(addr, size, dir);
> > +}
> > 
> 
> Kind regards,
> Oleksij Rempel
> 
> -- 
> Pengutronix e.K.                           |                             |
> Industrial Linux Solutions                 | http://www.pengutronix.de/  |
> Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
> Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |


-- 
Best regards,
  Antony Pavlov

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox