Re: [RFC PATCH 1/2] platform/x86: add Atom PMC quirk to disable SATA

["Rafael J. Wysocki" <rjw@rjwysocki.net>]

On Monday, September 25, 2017 9:21:09 PM CET Johannes Stezenbach wrote:
> SATA controller is enabled on Asus E200HA even though the
> machine doesn't use it (it has eMMC storage), however
> SATA being on blocks S0ix entry so we need to disable it.
> 
> Signed-off-by: Johannes Stezenbach <js@sig21.net>

Mika, Andy, Hans, any comments on this one?

> ---
>  drivers/platform/x86/pmc_atom.c | 33 +++++++++++++++++++++++++++++++++
>  1 file changed, 33 insertions(+)
> 
> diff --git a/drivers/platform/x86/pmc_atom.c b/drivers/platform/x86/pmc_atom.c
> index 8d13c86cc418..b5dd38712268 100644
> --- a/drivers/platform/x86/pmc_atom.c
> +++ b/drivers/platform/x86/pmc_atom.c
> @@ -17,6 +17,7 @@
>  
>  #include <linux/debugfs.h>
>  #include <linux/device.h>
> +#include <linux/dmi.h>
>  #include <linux/init.h>
>  #include <linux/io.h>
>  #include <linux/platform_data/x86/clk-pmc-atom.h>
> @@ -57,6 +58,9 @@ struct pmc_dev {
>  static struct pmc_dev pmc_device;
>  static u32 acpi_base_addr;
>  
> +static u32 quirks;
> +#define QUIRK_DISABLE_SATA BIT(0)
> +
>  static const struct pmc_clk byt_clks[] = {
>  	{
>  		.name = "xtal",
> @@ -271,6 +275,15 @@ static void pmc_hw_reg_setup(struct pmc_dev *pmc)
>  	 * - GPIO_SCORE shared IRQ
>  	 */
>  	pmc_reg_write(pmc, PMC_S0IX_WAKE_EN, (u32)PMC_WAKE_EN_SETTING);
> +
> +	if (quirks & QUIRK_DISABLE_SATA) {
> +		u32 func_dis;
> +
> +		pr_info("pmc: disable SATA IP\n");
> +		func_dis = pmc_reg_read(pmc, PMC_FUNC_DIS);
> +		func_dis |= BIT_SATA;
> +		pmc_reg_write(pmc, PMC_FUNC_DIS, func_dis);
> +	}
>  }
>  
>  #ifdef CONFIG_DEBUG_FS
> @@ -500,6 +513,24 @@ static struct pmc_notifier_block pmc_freeze_nb = {
>  };
>  #endif
>  
> +static int cht_asus_e200ha_cb(const struct dmi_system_id *id)
> +{
> +	pr_info("pmc: Asus E200HA detected\n");
> +	quirks |= QUIRK_DISABLE_SATA;
> +	return 1;
> +}
> +
> +static const struct dmi_system_id cht_table[] = {
> +	{
> +		.callback = cht_asus_e200ha_cb,
> +		.matches = {
> +			DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
> +			DMI_MATCH(DMI_PRODUCT_NAME, "E200HA"),
> +		},
> +	},
> +	{ }
> +};
> +
>  static int pmc_setup_dev(struct pci_dev *pdev, const struct pci_device_id *ent)
>  {
>  	struct pmc_dev *pmc = &pmc_device;
> @@ -526,6 +557,8 @@ static int pmc_setup_dev(struct pci_dev *pdev, const struct pci_device_id *ent)
>  
>  	pmc->map = map;
>  
> +	dmi_check_system(cht_table);
> +
>  	/* PMC hardware registers setup */
>  	pmc_hw_reg_setup(pmc);
>  
>