[PATCH v3 3/4] mfd: intel-m10-bmc: Add access table configuration to the regmap

From: Xu Yilun
Date: Mon Mar 01 2021 - 01:07:36 EST


From: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>

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@xxxxxxxxxxxxxxx>
Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
Reviewed-by: Tom Rix <trix@xxxxxxxxxx>
---
v2: Use the new macro M10BMC_LEGACY_BUILD_VER
v3: No change, rebased to 5.12-rc1
---
drivers/mfd/intel-m10-bmc.c | 13 +++++++++++++
include/linux/mfd/intel-m10-bmc.h | 5 ++++-
2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/mfd/intel-m10-bmc.c b/drivers/mfd/intel-m10-bmc.c
index 0d2c03f..1932101 100644
--- a/drivers/mfd/intel-m10-bmc.c
+++ b/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,
};

diff --git a/include/linux/mfd/intel-m10-bmc.h b/include/linux/mfd/intel-m10-bmc.h
index 4f1071f..c4eb38c 100644
--- a/include/linux/mfd/intel-m10-bmc.h
+++ b/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
--
2.7.4