--- zzzz-none-000/linux-3.10.107/arch/x86/kernel/pci-calgary_64.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/x86/kernel/pci-calgary_64.c	2021-02-04 17:41:59.000000000 +0000
@@ -1207,23 +1207,31 @@
 	return ret;
 }
 
-static inline int __init determine_tce_table_size(u64 ram)
+static inline int __init determine_tce_table_size(void)
 {
 	int ret;
 
 	if (specified_table_size != TCE_TABLE_SIZE_UNSPECIFIED)
 		return specified_table_size;
 
-	/*
-	 * Table sizes are from 0 to 7 (TCE_TABLE_SIZE_64K to
-	 * TCE_TABLE_SIZE_8M). Table size 0 has 8K entries and each
-	 * larger table size has twice as many entries, so shift the
-	 * max ram address by 13 to divide by 8K and then look at the
-	 * order of the result to choose between 0-7.
-	 */
-	ret = get_order(ram >> 13);
-	if (ret > TCE_TABLE_SIZE_8M)
+	if (is_kdump_kernel() && saved_max_pfn) {
+		/*
+		 * Table sizes are from 0 to 7 (TCE_TABLE_SIZE_64K to
+		 * TCE_TABLE_SIZE_8M). Table size 0 has 8K entries and each
+		 * larger table size has twice as many entries, so shift the
+		 * max ram address by 13 to divide by 8K and then look at the
+		 * order of the result to choose between 0-7.
+		 */
+		ret = get_order((saved_max_pfn * PAGE_SIZE) >> 13);
+		if (ret > TCE_TABLE_SIZE_8M)
+			ret = TCE_TABLE_SIZE_8M;
+	} else {
+		/*
+		 * Use 8M by default (suggested by Muli) if it's not
+		 * kdump kernel and saved_max_pfn isn't set.
+		 */
 		ret = TCE_TABLE_SIZE_8M;
+	}
 
 	return ret;
 }
@@ -1418,8 +1426,7 @@
 		return -ENOMEM;
 	}
 
-	specified_table_size = determine_tce_table_size((is_kdump_kernel() ?
-					saved_max_pfn : max_pfn) * PAGE_SIZE);
+	specified_table_size = determine_tce_table_size();
 
 	for (bus = 0; bus < MAX_PHB_BUS_NUM; bus++) {
 		struct calgary_bus_info *info = &bus_info[bus];