Re: [PATCH v6 0/5] PCI: Add support for PCI Enhanced Allocation "BARs"

[David Daney <ddaney@caviumnetworks.com>]

On 10/21/2015 08:14 AM, Bjorn Helgaas wrote:
[...]
> Applied to pci/enhanced-allocation for v4.4, thanks, David!
>
> I tweaked a couple trivial things and added a couple almost trivial patches
> on top.  Here are the additions; let me know if you see anything wrong.
>

Thanks for working with us on this.

Your additional changes look to be correct to me, I will give them a 
test within the next few days.

David Daney


> Bjorn
>
>
> commit 6457d085fade7d96a3aa6c5dca848fd82b4a4fa4
> Author: Bjorn Helgaas <bhelgaas@google.com>
> Date:   Wed Oct 21 09:34:15 2015 -0500
>
>      PCI: Make Enhanced Allocation bitmasks more obvious
>
>      Expand bitmask #defines completely.  This puts the shift in the code
>      instead of in the #define, but it makes it more obvious in the header file
>      how fields in the register are laid out.
>
>      No functional change.
>
>      Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index 364f98b..e8330b6 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -2195,7 +2195,7 @@ static int pci_ea_read(struct pci_dev *dev, int offset)
>   	int ent_size, ent_offset = offset;
>   	resource_size_t start, end;
>   	unsigned long flags;
> -	u32 dw0, base, max_offset;
> +	u32 dw0, bei, base, max_offset;
>   	u8 prop;
>   	bool support_64 = (sizeof(resource_size_t) >= 8);
>
> @@ -2208,20 +2208,21 @@ static int pci_ea_read(struct pci_dev *dev, int offset)
>   	if (!(dw0 & PCI_EA_ENABLE)) /* Entry not enabled */
>   		goto out;
>
> -	prop = PCI_EA_PP(dw0);
> +	bei = (dw0 & PCI_EA_BEI) >> 4;
> +	prop = (dw0 & PCI_EA_PP) >> 8;
> +
>   	/*
>   	 * If the Property is in the reserved range, try the Secondary
>   	 * Property instead.
>   	 */
>   	if (prop > PCI_EA_P_BRIDGE_IO && prop < PCI_EA_P_MEM_RESERVED)
> -		prop = PCI_EA_SP(dw0);
> +		prop = (dw0 & PCI_EA_SP) >> 16;
>   	if (prop > PCI_EA_P_BRIDGE_IO)
>   		goto out;
>
> -	res = pci_ea_get_resource(dev, PCI_EA_BEI(dw0), prop);
> +	res = pci_ea_get_resource(dev, bei, prop);
>   	if (!res) {
> -		dev_err(&dev->dev, "Unsupported EA entry BEI: %u\n",
> -			PCI_EA_BEI(dw0));
> +		dev_err(&dev->dev, "Unsupported EA entry BEI: %u\n", bei);
>   		goto out;
>   	}
>
> @@ -2293,7 +2294,7 @@ static int pci_ea_read(struct pci_dev *dev, int offset)
>   	res->end = end;
>   	res->flags = flags;
>   	dev_printk(KERN_DEBUG, &dev->dev, "EA - BEI %2u, Prop 0x%02x: %pR\n",
> -		   PCI_EA_BEI(dw0), prop, res);
> +		   bei, prop, res);
>   out:
>   	return offset + ent_size;
>   }
> diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h
> index f890876..1becea8 100644
> --- a/include/uapi/linux/pci_regs.h
> +++ b/include/uapi/linux/pci_regs.h
> @@ -361,7 +361,7 @@
>   #define PCI_EA_FIRST_ENT	4	/* First EA Entry in List */
>   #define PCI_EA_FIRST_ENT_BRIDGE	8	/* First EA Entry for Bridges */
>   #define  PCI_EA_ES		0x00000007 /* Entry Size */
> -#define  PCI_EA_BEI(x)	(((x) >> 4) & 0xf) /* BAR Equivalent Indicator */
> +#define  PCI_EA_BEI		0x000000f0 /* BAR Equivalent Indicator */
>   /* 0-5 map to BARs 0-5 respectively */
>   #define   PCI_EA_BEI_BAR0		0
>   #define   PCI_EA_BEI_BAR5		5
> @@ -372,8 +372,8 @@
>   #define   PCI_EA_BEI_VF_BAR0		9
>   #define   PCI_EA_BEI_VF_BAR5		14
>   #define   PCI_EA_BEI_RESERVED		15	/* Reserved - Treat like ENI */
> -#define  PCI_EA_PP(x)	(((x) >>  8) & 0xff)	/* Primary Properties */
> -#define  PCI_EA_SP(x)	(((x) >> 16) & 0xff)	/* Secondary Properties */
> +#define  PCI_EA_PP		0x0000ff00	/* Primary Properties */
> +#define  PCI_EA_SP		0x00ff0000	/* Secondary Properties */
>   #define   PCI_EA_P_MEM			0x00	/* Non-Prefetch Memory */
>   #define   PCI_EA_P_MEM_PREFETCH		0x01	/* Prefetchable Memory */
>   #define   PCI_EA_P_IO			0x02	/* I/O Space */
>
> commit 6985dcc83d70f019523ba9ff499898261f33c937
> Author: Bjorn Helgaas <bhelgaas@google.com>
> Date:   Wed Oct 21 09:53:39 2015 -0500
>
>      PCI: Expand Enhanced Allocation BAR output
>
>      An Enhanced Allocation Capability entry with BEI 0 fills in
>      dev->resource[0] just like a real BAR 0 would, but non-EA experts might not
>      connect "EA - BEI 0" with BAR 0.
>
>      Decode the EA jargon a little bit, e.g., change this:
>
>        pci 0002:01:00.0: EA - BEI  0, Prop 0x00: [mem 0x84300000-0x84303fff]
>
>      to this:
>
>        pci 0002:01:00.0: BAR 0: [mem 0x84300000-0x84303fff] (from Enhanced Allocation, properties 0x00)
>
>      Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index e8330b6..3a1454e 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -2293,8 +2293,20 @@ static int pci_ea_read(struct pci_dev *dev, int offset)
>   	res->start = start;
>   	res->end = end;
>   	res->flags = flags;
> -	dev_printk(KERN_DEBUG, &dev->dev, "EA - BEI %2u, Prop 0x%02x: %pR\n",
> -		   bei, prop, res);
> +
> +	if (bei <= PCI_EA_BEI_BAR5)
> +		dev_printk(KERN_DEBUG, &dev->dev, "BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
> +			   bei, res, prop);
> +	else if (bei == PCI_EA_BEI_ROM)
> +		dev_printk(KERN_DEBUG, &dev->dev, "ROM: %pR (from Enhanced Allocation, properties %#02x)\n",
> +			   res, prop);
> +	else if (bei >= PCI_EA_BEI_VF_BAR0 && bei <= PCI_EA_BEI_VF_BAR5)
> +		dev_printk(KERN_DEBUG, &dev->dev, "VF BAR %d: %pR (from Enhanced Allocation, properties %#02x)\n",
> +			   bei - PCI_EA_BEI_VF_BAR0, res, prop);
> +	else
> +		dev_printk(KERN_DEBUG, &dev->dev, "BEI %d res: %pR (from Enhanced Allocation, properties %#02x)\n",
> +			   bei, res, prop);
> +
>   out:
>   	return offset + ent_size;
>   }
>