Subject: Re: [PATCH 6/7] sky2: enable clocks before probe

From: Jeff Garzik <[email-masked]>
Date: Wed, 30 May 2007 09:56:18 -0400

Stephen Hemminger wrote:
> Some chips need to have internal clocks enabled (via PCI config)
> before the PCI space is readable.
> 
> Signed-off-by: Stephen Hemminger <[email-masked]>
> 
> ---
>  drivers/net/sky2.c |  102 ++++++++++++++++++++++++++++++++++++++---------------
>  drivers/net/sky2.h |   19 +++++++++
>  2 files changed, 92 insertions(+), 29 deletions(-)
> 
> --- a/drivers/net/sky2.c	2007-05-24 15:22:14.000000000 -0700
> +++ b/drivers/net/sky2.c	2007-05-24 15:22:33.000000000 -0700
> @@ -2524,10 +2524,6 @@ static int __devinit sky2_init(struct sk
>  		dev_warn(&hw->pdev->dev, "this driver not yet tested on this chip type\n"
>  			 "Please report success or failure to <[email-masked]>\n");
>  
> -	/* Make sure and enable all clocks */
> -	if (hw->chip_id == CHIP_ID_YUKON_EX || hw->chip_id == CHIP_ID_YUKON_EC_U)
> -		sky2_pci_write32(hw, PCI_DEV_REG3, 0);
> -
>  	hw->chip_rev = (sky2_read8(hw, B2_MAC_CFG) & CFG_CHIP_R_MSK) >> 4;
>  
>  	/* This rev is really old, and requires untested workarounds */
> @@ -3638,6 +3634,9 @@ static int __devinit sky2_probe(struct p
>  	if (!hw->st_le)
>  		goto err_out_iounmap;
>  
> +	/* On Yukon EC-U and EX need to force enabling all clocks */
> +	pci_write_config_dword(pdev, PCI_DEV_REG3, 0);
> +
>  	err = sky2_init(hw);
>  	if (err)
>  		goto err_out_iounmap;
> @@ -3822,8 +3821,7 @@ static int sky2_resume(struct pci_dev *p
>  	pci_enable_wake(pdev, PCI_D0, 0);
>  
>  	/* Re-enable all clocks */
> -	if (hw->chip_id == CHIP_ID_YUKON_EX || hw->chip_id == CHIP_ID_YUKON_EC_U)
> -		sky2_pci_write32(hw, PCI_DEV_REG3, 0);
> +	pci_write_config_dword(pdev, PCI_DEV_REG3, 0);

No explanation as to why the chip identity tests went away.  And in one 
of your code comments, it seems to imply that the chip tests are still 
present.