x86/mce/amd: Define threshold restart function for banks

Prepare for CMCI storm support by moving the common bank/block iterator code
to a helper function.

Include a parameter to switch the interrupt enable. This will be used by the
CMCI storm handling function.

Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Nikolay Borisov <nik.borisov@suse.com>
Link: https://lore.kernel.org/20251104-wip-mca-updates-v8-0-66c8eacf67b9@amd.com

Author: yghannam

arch/x86/kernel/cpu/mce/amd.c

@@ -471,6 +471,24 @@ static void threshold_restart_block(void *_tr)
 	wrmsr(tr->b->address, lo, hi);
 }
 
+static void threshold_restart_bank(unsigned int bank, bool intr_en)
+{
+	struct threshold_bank **thr_banks = this_cpu_read(threshold_banks);
+	struct threshold_block *block, *tmp;
+	struct thresh_restart tr;
+
+	if (!thr_banks || !thr_banks[bank])
+		return;
+
+	memset(&tr, 0, sizeof(tr));
+
+	list_for_each_entry_safe(block, tmp, &thr_banks[bank]->miscj, miscj) {
+		tr.b = block;
+		tr.b->interrupt_enable = intr_en;
+		threshold_restart_block(&tr);
+	}
+}
+
 static void mce_threshold_block_init(struct threshold_block *b, int offset)
 {
 	struct thresh_restart tr = {
@@ -814,24 +832,7 @@ static void amd_deferred_error_interrupt(void)
 
 static void amd_reset_thr_limit(unsigned int bank)
 {
-	struct threshold_bank **bp = this_cpu_read(threshold_banks);
-	struct threshold_block *block, *tmp;
-	struct thresh_restart tr;
-
-	/*
-	 * Validate that the threshold bank has been initialized already. The
-	 * handler is installed at boot time, but on a hotplug event the
-	 * interrupt might fire before the data has been initialized.
-	 */
-	if (!bp || !bp[bank])
-		return;
-
-	memset(&tr, 0, sizeof(tr));
-
-	list_for_each_entry_safe(block, tmp, &bp[bank]->miscj, miscj) {
-		tr.b = block;
-		threshold_restart_block(&tr);
-	}
+	threshold_restart_bank(bank, true);
 }
 
 /*