Re: [PATCH v3 09/13] pci: provide pci_enable_defaults()

[Andrew Jones <drjones@redhat.com>]

On Mon, Nov 14, 2016 at 05:28:07PM -0500, Peter Xu wrote:
> One helper function to set/clear specific bit in PCI_COMMAND register is
> introduced. Then, provide a function to do most of the common PCI init
> work.
> 
> Suggested-by: Andrew Jones <drjones@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  lib/pci.c | 19 +++++++++++++++++++
>  lib/pci.h |  2 ++
>  2 files changed, 21 insertions(+)
> 
> diff --git a/lib/pci.c b/lib/pci.c
> index 462c370..1c59e13 100644
> --- a/lib/pci.c
> +++ b/lib/pci.c
> @@ -7,6 +7,18 @@
>  #include "pci.h"
>  #include "asm/pci.h"
>  
> +void pci_cmd_set_clr(struct pci_dev *dev, uint16_t set, uint16_t clr)
> +{
> +	uint16_t val = pci_config_readw(dev->bdf, PCI_COMMAND);
> +
> +	/* No overlap is allowed */
> +	assert((set & clr) == 0);
> +	val |= set;
> +	val &= ~clr;
> +
> +	pci_config_writew(dev->bdf, PCI_COMMAND, val);
> +}
> +
>  bool pci_dev_exists(pcidevaddr_t dev)
>  {
>  	return (pci_config_readw(dev, PCI_VENDOR_ID) != 0xffff &&
> @@ -242,3 +254,10 @@ void pci_scan_bars(struct pci_dev *dev)
>  		}
>  	}
>  }
> +
> +void pci_enable_defaults(struct pci_dev *dev)
> +{
> +	pci_scan_bars(dev);
> +	/* Enable device DMA operations */
> +	pci_cmd_set_clr(dev, PCI_COMMAND_MASTER, 0);
> +}
> diff --git a/lib/pci.h b/lib/pci.h
> index 338ad51..1e7be27 100644
> --- a/lib/pci.h
> +++ b/lib/pci.h
> @@ -25,6 +25,8 @@ struct pci_dev {
>  
>  void pci_dev_init(struct pci_dev *dev, pcidevaddr_t bdf);
>  void pci_scan_bars(struct pci_dev *dev);
> +void pci_cmd_set_clr(struct pci_dev *dev, uint16_t set, uint16_t clr);
> +void pci_enable_defaults(struct pci_dev *dev);

Don't forget the [pointless] externs on these functions for this patch,
and the ones that introduced the functions above.

>  
>  extern bool pci_probe(void);
>  extern void pci_print(void);
> -- 
> 2.7.4

I think I already gave my r-b on this patch last time, but anyway, here it
is again

Reviewed-by: Andrew Jones <drjones@redhat.com>

drew