Re: [PATCH 10/16] iwlagn: remove un-needed configuration

[Stanislaw Gruszka <sgruszka@redhat.com>]

On Fri, Apr 08, 2011 at 08:30:30AM -0700, Wey-Yi Guy wrote:
> +	lctl = iwl_pcie_link_ctl(priv);
> +	if ((lctl & PCI_CFG_LINK_CTRL_VAL_L1_EN) ==
> +				PCI_CFG_LINK_CTRL_VAL_L1_EN) {
> +		/* L1-ASPM enabled; disable(!) L0S  */
> +		iwl_set_bit(priv, CSR_GIO_REG,
> +				CSR_GIO_REG_VAL_L0S_ENABLED);
> +		IWL_DEBUG_POWER(priv, "L1 Enabled; Disabling L0S\n");
> +	} else {
> +		/* L1-ASPM disabled; enable(!) L0S */
> +		iwl_clear_bit(priv, CSR_GIO_REG,
> +				CSR_GIO_REG_VAL_L0S_ENABLED);
> +		IWL_DEBUG_POWER(priv, "L1 Disabled; Enabling L0S\n");
>  	}

In

commit 1a7123cdd9f49cf1c908fb2c16d26f279c88d8c9
Author: John W. Linville <linville@tuxdriver.com>
Date:   Thu Aug 5 14:39:31 2010 -0400

    iwlwifi: disable aspm by default

we claim to disable ASPM (including L0S), but here we
enable L0S anyway. Perhaps this is the reason why we
still get reports about device disappear:
https://bugzilla.redhat.com/show_bug.cgi?id=642966

We also have code from:

commit e7cad69cdab4d6f0caadbcdd58b54214243ba98a
Author: Grumbach, Emmanuel <emmanuel.grumbach@intel.com>
Date:   Thu Nov 18 03:47:38 2010 -0800

    iwlagn: Enable PCI L1 ACTIVE state after uCode has been loaded

that seems to enable L1 ASPM as well.

I think these bits should be removed from iwlagn driver, or better
root cause of device disappear from bus should be identified and fixed
(not sure if this is iwlagn driver/firmware problem or bios or
pci driver problem, however) to allow to use ASPM.

Stanislaw