mei: me: d0i3: add flag to indicate D0i3 support

Detect d0i3 low power state during hw configuration,
the value is set in HFS_1 pci config reigister.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/mei/hw-me-regs.h

@@ -123,6 +123,7 @@
 
 /* Host Firmware Status Registers in PCI Config Space */
 #define PCI_CFG_HFS_1         0x40
+#  define PCI_CFG_HFS_1_D0I3_MSK     0x80000000
 #define PCI_CFG_HFS_2         0x48
 #define PCI_CFG_HFS_3         0x60
 #define PCI_CFG_HFS_4         0x64

drivers/misc/mei/hw-me.c

@@ -176,12 +176,20 @@ static int mei_me_fw_status(struct mei_device *dev,
  */
 static void mei_me_hw_config(struct mei_device *dev)
 {
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
 	struct mei_me_hw *hw = to_me_hw(dev);
-	u32 hcsr = mei_hcsr_read(dev);
+	u32 hcsr, reg;
+
 	/* Doesn't change in runtime */
+	hcsr = mei_hcsr_read(dev);
 	dev->hbuf_depth = (hcsr & H_CBD) >> 24;
 
 	hw->pg_state = MEI_PG_OFF;
+
+	reg = 0;
+	pci_read_config_dword(pdev, PCI_CFG_HFS_1, &reg);
+	hw->d0i3_supported =
+		((reg & PCI_CFG_HFS_1_D0I3_MSK) == PCI_CFG_HFS_1_D0I3_MSK);
 }
 
 /**

drivers/misc/mei/hw-me.h

@@ -50,13 +50,15 @@ struct mei_cfg {
  * struct mei_me_hw - me hw specific data
  *
  * @cfg: per device generation config and ops
- * @mem_addr:  io memory address
- * @pg_state:      power gating state
+ * @mem_addr: io memory address
+ * @pg_state: power gating state
+ * @d0i3_supported: di03 support
  */
 struct mei_me_hw {
 	const struct mei_cfg *cfg;
 	void __iomem *mem_addr;
 	enum mei_pg_state pg_state;
+	bool d0i3_supported;
 };
 
 #define to_me_hw(dev) (struct mei_me_hw *)((dev)->hw)