x86: pmc_atom: Expose contents of PSS

The PSS register reflects the power state of each island on SoC. It would be
useful to know which of the islands is on or off at the momemnt.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Aubrey Li <aubrey.li@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Kumar P. Mahesh <mahesh.kumar.p@intel.com>
Link: http://lkml.kernel.org/r/1421253575-22509-6-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/include/asm/pmc_atom.h

@@ -53,6 +53,28 @@
 /* Sleep state counter is in units of of 32us */
 #define	PMC_TMR_SHIFT		5
 
+/* Power status of power islands */
+#define	PMC_PSS			0x98
+
+#define PMC_PSS_BIT_GBE			BIT(0)
+#define PMC_PSS_BIT_SATA		BIT(1)
+#define PMC_PSS_BIT_HDA			BIT(2)
+#define PMC_PSS_BIT_SEC			BIT(3)
+#define PMC_PSS_BIT_PCIE		BIT(4)
+#define PMC_PSS_BIT_LPSS		BIT(5)
+#define PMC_PSS_BIT_LPE			BIT(6)
+#define PMC_PSS_BIT_DFX			BIT(7)
+#define PMC_PSS_BIT_USH_CTRL		BIT(8)
+#define PMC_PSS_BIT_USH_SUS		BIT(9)
+#define PMC_PSS_BIT_USH_VCCS		BIT(10)
+#define PMC_PSS_BIT_USH_VCCA		BIT(11)
+#define PMC_PSS_BIT_OTG_CTRL		BIT(12)
+#define PMC_PSS_BIT_OTG_VCCS		BIT(13)
+#define PMC_PSS_BIT_OTG_VCCA_CLK	BIT(14)
+#define PMC_PSS_BIT_OTG_VCCA		BIT(15)
+#define PMC_PSS_BIT_USB			BIT(16)
+#define PMC_PSS_BIT_USB_SUS		BIT(17)
+
 /* These registers reflect D3 status of functions */
 #define	PMC_D3_STS_0		0xA0
 

arch/x86/kernel/pmc_atom.c

@@ -36,12 +36,12 @@ struct pmc_dev {
 static struct pmc_dev pmc_device;
 static u32 acpi_base_addr;
 
-struct pmc_dev_map {
+struct pmc_bit_map {
 	const char *name;
 	u32 bit_mask;
 };
 
-static const struct pmc_dev_map dev_map[] = {
+static const struct pmc_bit_map dev_map[] = {
 	{"0  - LPSS1_F0_DMA",		BIT_LPSS1_F0_DMA},
 	{"1  - LPSS1_F1_PWM1",		BIT_LPSS1_F1_PWM1},
 	{"2  - LPSS1_F2_PWM2",		BIT_LPSS1_F2_PWM2},
@@ -80,6 +80,27 @@ static const struct pmc_dev_map dev_map[] = {
 	{"35 - DFX",			BIT_DFX},
 };
 
+static const struct pmc_bit_map pss_map[] = {
+	{"0  - GBE",			PMC_PSS_BIT_GBE},
+	{"1  - SATA",			PMC_PSS_BIT_SATA},
+	{"2  - HDA",			PMC_PSS_BIT_HDA},
+	{"3  - SEC",			PMC_PSS_BIT_SEC},
+	{"4  - PCIE",			PMC_PSS_BIT_PCIE},
+	{"5  - LPSS",			PMC_PSS_BIT_LPSS},
+	{"6  - LPE",			PMC_PSS_BIT_LPE},
+	{"7  - DFX",			PMC_PSS_BIT_DFX},
+	{"8  - USH_CTRL",		PMC_PSS_BIT_USH_CTRL},
+	{"9  - USH_SUS",		PMC_PSS_BIT_USH_SUS},
+	{"10 - USH_VCCS",		PMC_PSS_BIT_USH_VCCS},
+	{"11 - USH_VCCA",		PMC_PSS_BIT_USH_VCCA},
+	{"12 - OTG_CTRL",		PMC_PSS_BIT_OTG_CTRL},
+	{"13 - OTG_VCCS",		PMC_PSS_BIT_OTG_VCCS},
+	{"14 - OTG_VCCA_CLK",		PMC_PSS_BIT_OTG_VCCA_CLK},
+	{"15 - OTG_VCCA",		PMC_PSS_BIT_OTG_VCCA},
+	{"16 - USB",			PMC_PSS_BIT_USB},
+	{"17 - USB_SUS",		PMC_PSS_BIT_USB_SUS},
+};
+
 static inline u32 pmc_reg_read(struct pmc_dev *pmc, int reg_offset)
 {
 	return readl(pmc->regmap + reg_offset);
@@ -167,6 +188,32 @@ static const struct file_operations pmc_dev_state_ops = {
 	.release	= single_release,
 };
 
+static int pmc_pss_state_show(struct seq_file *s, void *unused)
+{
+	struct pmc_dev *pmc = s->private;
+	u32 pss = pmc_reg_read(pmc, PMC_PSS);
+	int pss_index;
+
+	for (pss_index = 0; pss_index < ARRAY_SIZE(pss_map); pss_index++) {
+		seq_printf(s, "Island: %-32s\tState: %s\n",
+			pss_map[pss_index].name,
+			pss_map[pss_index].bit_mask & pss ? "Off" : "On");
+	}
+	return 0;
+}
+
+static int pmc_pss_state_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, pmc_pss_state_show, inode->i_private);
+}
+
+static const struct file_operations pmc_pss_state_ops = {
+	.open		= pmc_pss_state_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
 static int pmc_sleep_tmr_show(struct seq_file *s, void *unused)
 {
 	struct pmc_dev *pmc = s->private;
@@ -216,9 +263,17 @@ static int pmc_dbgfs_register(struct pmc_dev *pmc, struct pci_dev *pdev)
 	f = debugfs_create_file("dev_state", S_IFREG | S_IRUGO,
 				dir, pmc, &pmc_dev_state_ops);
 	if (!f) {
-		dev_err(&pdev->dev, "dev_states register failed\n");
+		dev_err(&pdev->dev, "dev_state register failed\n");
 		goto err;
 	}
+
+	f = debugfs_create_file("pss_state", S_IFREG | S_IRUGO,
+				dir, pmc, &pmc_pss_state_ops);
+	if (!f) {
+		dev_err(&pdev->dev, "pss_state register failed\n");
+		goto err;
+	}
+
 	f = debugfs_create_file("sleep_state", S_IFREG | S_IRUGO,
 				dir, pmc, &pmc_sleep_tmr_ops);
 	if (!f) {