arm: mvebu: turris_omnia: Read DDR speed from EEPROM
Some Turris Omnia boards experience memory issues, and by
experimentation we found that some of these issues can be solved by
slowing DDR speed.
Add a new field in the extended EEPROM information structure, ddr_speed.
Support several values in this field (for now 1066F, 1333H, and the
default, 1600K) and use it to overwrite the DDR topology parameters
used by the DDR training algorithm.
Signed-off-by: Marek Behún <kabel@kernel.org>
diff --git a/board/CZ.NIC/turris_omnia/turris_omnia.c b/board/CZ.NIC/turris_omnia/turris_omnia.c
index c2f91b7..544784e 100644
--- a/board/CZ.NIC/turris_omnia/turris_omnia.c
+++ b/board/CZ.NIC/turris_omnia/turris_omnia.c
@@ -431,7 +431,8 @@
u32 crc;
/* second part (only considered if crc2 is not all-ones) */
- u8 reserved[44];
+ char ddr_speed[5];
+ u8 reserved[39];
u32 crc2;
};
@@ -520,6 +521,26 @@
return ram_size;
}
+static const char *omnia_get_ddr_speed(void)
+{
+ struct omnia_eeprom oep;
+ static char speed[sizeof(oep.ddr_speed) + 1];
+
+ if (!omnia_read_eeprom(&oep))
+ return NULL;
+
+ if (!is_omnia_eeprom_second_part_valid(&oep))
+ return NULL;
+
+ if (!oep.ddr_speed[0] || oep.ddr_speed[0] == 0xff)
+ return NULL;
+
+ memcpy(&speed, &oep.ddr_speed, sizeof(oep.ddr_speed));
+ speed[sizeof(speed) - 1] = '\0';
+
+ return speed;
+}
+
static const char * const omnia_get_mcu_type(void)
{
static char result[] = "xxxxxxx (with peripheral resets)";
@@ -634,12 +655,84 @@
{0} /* timing parameters */
};
+static const struct omnia_ddr_speed {
+ char name[5];
+ u8 speed_bin;
+ u8 freq;
+} omnia_ddr_speeds[] = {
+ { "1066F", SPEED_BIN_DDR_1066F, MV_DDR_FREQ_533 },
+ { "1333H", SPEED_BIN_DDR_1333H, MV_DDR_FREQ_667 },
+ { "1600K", SPEED_BIN_DDR_1600K, MV_DDR_FREQ_800 },
+};
+
+static const struct omnia_ddr_speed *find_ddr_speed_setting(const char *name)
+{
+ for (int i = 0; i < ARRAY_SIZE(omnia_ddr_speeds); ++i)
+ if (!strncmp(name, omnia_ddr_speeds[i].name, 5))
+ return &omnia_ddr_speeds[i];
+
+ return NULL;
+}
+
+bool omnia_valid_ddr_speed(const char *name)
+{
+ return find_ddr_speed_setting(name) != NULL;
+}
+
+void omnia_print_ddr_speeds(void)
+{
+ for (int i = 0; i < ARRAY_SIZE(omnia_ddr_speeds); ++i)
+ printf("%.5s%s", omnia_ddr_speeds[i].name,
+ i == ARRAY_SIZE(omnia_ddr_speeds) - 1 ? "\n" : ", ");
+}
+
+static void fixup_speed_in_ddr_topology(struct mv_ddr_topology_map *topology)
+{
+ typeof(topology->interface_params[0]) *params;
+ const struct omnia_ddr_speed *setting;
+ const char *speed;
+ static bool done;
+
+ if (done)
+ return;
+
+ done = true;
+
+ speed = omnia_get_ddr_speed();
+ if (!speed)
+ return;
+
+ setting = find_ddr_speed_setting(speed);
+ if (!setting) {
+ printf("Unsupported value %s for DDR3 speed in EEPROM!\n",
+ speed);
+ return;
+ }
+
+ params = &topology->interface_params[0];
+
+ /* don't inform if we are not changing the speed from the default one */
+ if (params->speed_bin_index == setting->speed_bin)
+ return;
+
+ printf("Fixing up DDR3 speed (EEPROM defines %s)\n", speed);
+
+ params->speed_bin_index = setting->speed_bin;
+ params->memory_freq = setting->freq;
+}
+
struct mv_ddr_topology_map *mv_ddr_topology_map_get(void)
{
+ struct mv_ddr_topology_map *topology;
+
if (omnia_get_ram_size_gb() == 2)
- return &board_topology_map_2g;
+ topology = &board_topology_map_2g;
else
- return &board_topology_map_1g;
+ topology = &board_topology_map_1g;
+
+ fixup_speed_in_ddr_topology(topology);
+
+ return topology;
}
static int set_regdomain(void)