mfd: intel-m10-bmc: Add access table configuration to the regmap

This patch adds access tables to the MAX 10 BMC regmap. This prevents
the host from accessing the unwanted I/O space. It also filters out the
invalid outputs when reading the regmap debugfs interface.
Signed-off-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Xu Yilun <yilun.xu@intel.com>
Reviewed-by: Tom Rix <trix@redhat.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/intel-m10-bmc.c

@@ -23,10 +23,23 @@ static struct mfd_cell m10bmc_pacn3000_subdevs[] = {
 	{ .name = "n3000bmc-secure" },
 };
 
+static const struct regmap_range m10bmc_regmap_range[] = {
+	regmap_reg_range(M10BMC_LEGACY_BUILD_VER, M10BMC_LEGACY_BUILD_VER),
+	regmap_reg_range(M10BMC_SYS_BASE, M10BMC_SYS_END),
+	regmap_reg_range(M10BMC_FLASH_BASE, M10BMC_FLASH_END),
+};
+
+static const struct regmap_access_table m10bmc_access_table = {
+	.yes_ranges	= m10bmc_regmap_range,
+	.n_yes_ranges	= ARRAY_SIZE(m10bmc_regmap_range),
+};
+
 static struct regmap_config intel_m10bmc_regmap_config = {
 	.reg_bits = 32,
 	.val_bits = 32,
 	.reg_stride = 4,
+	.wr_table = &m10bmc_access_table,
+	.rd_table = &m10bmc_access_table,
 	.max_register = M10BMC_MEM_END,
 };
 

include/linux/mfd/intel-m10-bmc.h

@@ -11,7 +11,10 @@
 
 #define M10BMC_LEGACY_BUILD_VER		0x300468
 #define M10BMC_SYS_BASE			0x300800
-#define M10BMC_MEM_END			0x1fffffff
+#define M10BMC_SYS_END			0x300fff
+#define M10BMC_FLASH_BASE		0x10000000
+#define M10BMC_FLASH_END		0x1fffffff
+#define M10BMC_MEM_END			M10BMC_FLASH_END
 
 /* Register offset of system registers */
 #define NIOS2_FW_VERSION		0x0