From: Michael J. Ruhl <michael.j.ruhl@intel.com>
Date: Sun, 13 Jul 2025 17:29:40 +0000 (-0400)
Subject: platform/x86/intel/pmt: add register access helpers
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f57b32cb4adb28b62f61c4729f7b85f55518cb2b;p=thirdparty%2Fkernel%2Fstable.git

platform/x86/intel/pmt: add register access helpers

The control register is used in a read/modify/write pattern.
The status register is used in a read/check bit pattern.

Add helpers to eliminate common code.

Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Link: https://lore.kernel.org/r/20250713172943.7335-11-michael.j.ruhl@intel.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---

diff --git a/drivers/platform/x86/intel/pmt/crashlog.c b/drivers/platform/x86/intel/pmt/crashlog.c
index 23b3971da40ac..ed781548e59d2 100644
--- a/drivers/platform/x86/intel/pmt/crashlog.c
+++ b/drivers/platform/x86/intel/pmt/crashlog.c
@@ -64,20 +64,40 @@ struct pmt_crashlog_priv {
 /*
  * I/O
  */
-static bool pmt_crashlog_complete(struct intel_pmt_entry *entry)
+
+/* Read, modify, write the control register, setting or clearing @bit based on @set */
+static void pmt_crashlog_rmw(struct intel_pmt_entry *entry, u32 bit, bool set)
 {
-	u32 control = readl(entry->disc_table + CONTROL_OFFSET);
+	u32 reg = readl(entry->disc_table + CONTROL_OFFSET);
+
+	reg &= ~CRASHLOG_FLAG_TRIGGER_MASK;
+
+	if (set)
+		reg |= bit;
+	else
+		reg &= ~bit;
+
+	writel(reg, entry->disc_table + CONTROL_OFFSET);
+}
+
+/* Read the status register and see if the specified @bit is set */
+static bool pmt_crashlog_rc(struct intel_pmt_entry *entry, u32 bit)
+{
+	u32 reg = readl(entry->disc_table + CONTROL_OFFSET);
+
+	return !!(reg & bit);
+}
 
+static bool pmt_crashlog_complete(struct intel_pmt_entry *entry)
+{
 	/* return current value of the crashlog complete flag */
-	return !!(control & CRASHLOG_FLAG_TRIGGER_COMPLETE);
+	return pmt_crashlog_rc(entry, CRASHLOG_FLAG_TRIGGER_COMPLETE);
 }
 
 static bool pmt_crashlog_disabled(struct intel_pmt_entry *entry)
 {
-	u32 control = readl(entry->disc_table + CONTROL_OFFSET);
-
 	/* return current value of the crashlog disabled flag */
-	return !!(control & CRASHLOG_FLAG_DISABLE);
+	return pmt_crashlog_rc(entry, CRASHLOG_FLAG_DISABLE);
 }
 
 static bool pmt_crashlog_supported(struct intel_pmt_entry *entry)
@@ -98,37 +118,17 @@ 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);
-
-	/* clear trigger bits so we are only modifying disable flag */
-	control &= ~CRASHLOG_FLAG_TRIGGER_MASK;
-
-	if (disable)
-		control |= CRASHLOG_FLAG_DISABLE;
-	else
-		control &= ~CRASHLOG_FLAG_DISABLE;
-
-	writel(control, entry->disc_table + CONTROL_OFFSET);
+	pmt_crashlog_rmw(entry, CRASHLOG_FLAG_DISABLE, disable);
 }
 
 static void pmt_crashlog_set_clear(struct intel_pmt_entry *entry)
 {
-	u32 control = readl(entry->disc_table + CONTROL_OFFSET);
-
-	control &= ~CRASHLOG_FLAG_TRIGGER_MASK;
-	control |= CRASHLOG_FLAG_TRIGGER_CLEAR;
-
-	writel(control, entry->disc_table + CONTROL_OFFSET);
+	pmt_crashlog_rmw(entry, CRASHLOG_FLAG_TRIGGER_CLEAR, true);
 }
 
 static void pmt_crashlog_set_execute(struct intel_pmt_entry *entry)
 {
-	u32 control = readl(entry->disc_table + CONTROL_OFFSET);
-
-	control &= ~CRASHLOG_FLAG_TRIGGER_MASK;
-	control |= CRASHLOG_FLAG_TRIGGER_EXECUTE;
-
-	writel(control, entry->disc_table + CONTROL_OFFSET);
+	pmt_crashlog_rmw(entry, CRASHLOG_FLAG_TRIGGER_EXECUTE, true);
 }
 
 /*