[PATCH 2/4] platform/x86/intel/pmt: update to bit access

["Michael J. Ruhl" <michael.j.ruhl@intel.com>]

The current usage of BIT offsets limits adding new
functionality to the crashlog register access.

Update the bit mask #defines to use a bit defined
structure.

Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
---
 drivers/platform/x86/intel/pmt/crashlog.c | 116 +++++++++++++++-------
 1 file changed, 79 insertions(+), 37 deletions(-)

diff --git a/drivers/platform/x86/intel/pmt/crashlog.c b/drivers/platform/x86/intel/pmt/crashlog.c
index 952bfe341f53..dba7e7c1585d 100644
--- a/drivers/platform/x86/intel/pmt/crashlog.c
+++ b/drivers/platform/x86/intel/pmt/crashlog.c
@@ -22,29 +22,12 @@
 /* Crashlog discovery header types */
 #define CRASH_TYPE_OOBMSM	1
 
-/* Control Flags */
-#define CRASHLOG_FLAG_DISABLE		BIT(28)
-
-/*
- * Bits 29 and 30 control the state of bit 31.
- *
- * Bit 29 will clear bit 31, if set, allowing a new crashlog to be captured.
- * Bit 30 will immediately trigger a crashlog to be generated, setting bit 31.
- * Bit 31 is the read-only status with a 1 indicating log is complete.
- */
-#define CRASHLOG_FLAG_TRIGGER_CLEAR	BIT(29)
-#define CRASHLOG_FLAG_TRIGGER_EXECUTE	BIT(30)
-#define CRASHLOG_FLAG_TRIGGER_COMPLETE	BIT(31)
-#define CRASHLOG_FLAG_TRIGGER_MASK	GENMASK(31, 28)
-
 /* Crashlog Discovery Header */
 #define CONTROL_OFFSET		0x0
 #define GUID_OFFSET		0x4
 #define BASE_OFFSET		0x8
 #define SIZE_OFFSET		0xC
 #define GET_ACCESS(v)		((v) & GENMASK(3, 0))
-#define GET_TYPE(v)		(((v) & GENMASK(7, 4)) >> 4)
-#define GET_VERSION(v)		(((v) & GENMASK(19, 16)) >> 16)
 /* size is in bytes */
 #define GET_SIZE(v)		((v) * sizeof(u32))
 
@@ -54,6 +37,39 @@ struct crashlog_entry {
 	struct mutex			control_mutex;
 };
 
+struct type1_ver0_base {
+	u32 access_type:	4;  /* ro     0:3  */
+	u32 crash_type:		4;  /* ro     4:7  */
+	u32 count:		8;  /* ro     8:15 */
+	u32 version:		4;  /* ro    16:19 */
+	u32 rsvd:		8;  /* ro    20:27 */
+	u32 disable:		1;  /* rw    28:28 */
+	/*
+	 * Bits 29 and 30 control the state of bit 31.
+	 *
+	 * Bit 29 will clear bit 31, if set, allowing a new crashlog to be captured.
+	 * Bit 30 will immediately trigger a crashlog to be generated, setting bit 31.
+	 * Bit 31 is the read-only status with a 1 indicating log is complete.
+	 */
+	u32 clear:		1;  /* rw    29:29 */
+	u32 manual:		1;  /* rw/1s 30:30 */
+	u32 complete:		1;  /* ro/v  31:31 */
+};
+
+struct crashlog_status {
+	union {
+		struct type1_ver0_base stat;
+		u32 status;
+	};
+};
+
+struct crashlog_control {
+	union {
+		struct type1_ver0_base ctrl;
+		u32 control;
+	};
+};
+
 struct pmt_crashlog_priv {
 	int			num_entries;
 	struct crashlog_entry	entry[];
@@ -64,27 +80,34 @@ struct pmt_crashlog_priv {
  */
 static bool pmt_crashlog_complete(struct intel_pmt_entry *entry)
 {
-	u32 control = readl(entry->disc_table + CONTROL_OFFSET);
+	struct crashlog_status status = {
+		.status = readl(entry->disc_table + CONTROL_OFFSET),
+	};
 
 	/* return current value of the crashlog complete flag */
-	return !!(control & CRASHLOG_FLAG_TRIGGER_COMPLETE);
+	return status.stat.complete;
+
 }
 
 static bool pmt_crashlog_disabled(struct intel_pmt_entry *entry)
 {
-	u32 control = readl(entry->disc_table + CONTROL_OFFSET);
+	struct crashlog_status status = {
+		.status = readl(entry->disc_table + CONTROL_OFFSET),
+	};
 
 	/* return current value of the crashlog disabled flag */
-	return !!(control & CRASHLOG_FLAG_DISABLE);
+	return status.stat.disable;
 }
 
 static bool pmt_crashlog_supported(struct intel_pmt_entry *entry)
 {
-	u32 discovery_header = readl(entry->disc_table + CONTROL_OFFSET);
+	struct crashlog_control discovery_header = {
+		.control = readl(entry->disc_table + CONTROL_OFFSET),
+	};
 	u32 crash_type, version;
 
-	crash_type = GET_TYPE(discovery_header);
-	version = GET_VERSION(discovery_header);
+	crash_type = discovery_header.ctrl.crash_type;
+	version = discovery_header.ctrl.version;
 
 	/*
 	 * Currently we only recognize OOBMSM version 0 devices.
@@ -96,37 +119,53 @@ static bool pmt_crashlog_supported(struct intel_pmt_entry *entry)
 static void pmt_crashlog_set_disable(struct intel_pmt_entry *entry,
 				     bool disable)
 {
-	u32 control = readl(entry->disc_table + CONTROL_OFFSET);
+	struct crashlog_control control = {
+		.control = readl(entry->disc_table + CONTROL_OFFSET),
+	};
 
 	/* clear trigger bits so we are only modifying disable flag */
-	control &= ~CRASHLOG_FLAG_TRIGGER_MASK;
+	control.ctrl.clear = 0;
+	control.ctrl.manual = 0;
+	control.ctrl.complete = 0;
 
 	if (disable)
-		control |= CRASHLOG_FLAG_DISABLE;
+		control.ctrl.disable = 1;
 	else
-		control &= ~CRASHLOG_FLAG_DISABLE;
+		control.ctrl.disable = 0;
 
-	writel(control, entry->disc_table + CONTROL_OFFSET);
+	writel(control.control, entry->disc_table + CONTROL_OFFSET);
 }
 
 static void pmt_crashlog_set_clear(struct intel_pmt_entry *entry)
 {
-	u32 control = readl(entry->disc_table + CONTROL_OFFSET);
+	struct crashlog_control control = {
+		.control = readl(entry->disc_table + CONTROL_OFFSET),
+	};
 
-	control &= ~CRASHLOG_FLAG_TRIGGER_MASK;
-	control |= CRASHLOG_FLAG_TRIGGER_CLEAR;
+	/* clear trigger bits so we are only modifying disable flag */
+	control.ctrl.disable = 0;
+	control.ctrl.manual = 0;
+	control.ctrl.complete = 0;
 
-	writel(control, entry->disc_table + CONTROL_OFFSET);
+	control.ctrl.clear = 1;
+
+	writel(control.control, entry->disc_table + CONTROL_OFFSET);
 }
 
 static void pmt_crashlog_set_execute(struct intel_pmt_entry *entry)
 {
-	u32 control = readl(entry->disc_table + CONTROL_OFFSET);
+	struct crashlog_control control = {
+		.control = readl(entry->disc_table + CONTROL_OFFSET),
+	};
+
+	/* clear trigger bits so we are only modifying disable flag */
+	control.ctrl.disable = 0;
+	control.ctrl.clear = 0;
+	control.ctrl.complete = 0;
 
-	control &= ~CRASHLOG_FLAG_TRIGGER_MASK;
-	control |= CRASHLOG_FLAG_TRIGGER_EXECUTE;
+	control.ctrl.manual = 1;
 
-	writel(control, entry->disc_table + CONTROL_OFFSET);
+	writel(control.control, entry->disc_table + CONTROL_OFFSET);
 }
 
 /*
@@ -304,6 +343,9 @@ static int pmt_crashlog_probe(struct auxiliary_device *auxdev,
 	size_t size;
 	int i, ret;
 
+	BUILD_BUG_ON(sizeof(struct crashlog_control) != sizeof(u32));
+	BUILD_BUG_ON(sizeof(struct crashlog_status) != sizeof(u32));
+
 	size = struct_size(priv, entry, intel_vsec_dev->num_resources);
 	priv = devm_kzalloc(&auxdev->dev, size, GFP_KERNEL);
 	if (!priv)
-- 
2.49.0