iot2050: Add support for configuring M.2 connector
The M.2 slots of the related IOT2050 variant need to be configured
according to the plugged cards. This tries to detect the card using the
M.2 configuration pins of the B-key slot. If that fails, a U-Boot
environment variable can be set to configure manually. This variable is
write-permitted also in secure boot mode as it is not able to undermine
the integrity of the booted system.
The configuration is then applied to mux the serdes and to fix up the
device tree passed to or loaded by the bootloader. The fix-ups are
coming from device tree overlays that are embedded into the firmware
image and there also integrity protected. The OS remains free to load
a device tree to which they do not apply: U-Boot will not fail to boot
in that case.
Based on original patch by Chao Zeng.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
diff --git a/board/siemens/iot2050/board.c b/board/siemens/iot2050/board.c
index 2735ae3..df705b7 100644
--- a/board/siemens/iot2050/board.c
+++ b/board/siemens/iot2050/board.c
@@ -1,7 +1,7 @@
// SPDX-License-Identifier: GPL-2.0+
/*
* Board specific initialization for IOT2050
- * Copyright (c) Siemens AG, 2018-2021
+ * Copyright (c) Siemens AG, 2018-2022
*
* Authors:
* Le Jin <le.jin@siemens.com>
@@ -11,9 +11,11 @@
#include <common.h>
#include <bootstage.h>
#include <dm.h>
+#include <fdt_support.h>
#include <i2c.h>
#include <led.h>
#include <malloc.h>
+#include <mapmem.h>
#include <net.h>
#include <phy.h>
#include <spl.h>
@@ -47,6 +49,114 @@
DECLARE_GLOBAL_DATA_PTR;
+struct gpio_config {
+ const char *gpio_name;
+ const char *label;
+};
+
+enum m2_connector_mode {
+ BKEY_PCIEX2 = 0,
+ BKEY_PCIE_EKEY_PCIE,
+ BKEY_USB30_EKEY_PCIE,
+ CONNECTOR_MODE_INVALID
+};
+
+struct m2_config_pins {
+ int config[4];
+};
+
+struct serdes_mux_control {
+ int ctrl_usb30_pcie0_lane0;
+ int ctrl_pcie1_pcie0;
+ int ctrl_usb30_pcie0_lane1;
+};
+
+struct m2_config_table {
+ struct m2_config_pins config_pins;
+ enum m2_connector_mode mode;
+};
+
+static const struct gpio_config serdes_mux_ctl_pin_info[] = {
+ {"gpio@600000_88", "CTRL_USB30_PCIE0_LANE0"},
+ {"gpio@600000_82", "CTRL_PCIE1_PCIE0"},
+ {"gpio@600000_89", "CTRL_USB30_PCIE0_LANE1"},
+};
+
+static const struct gpio_config m2_bkey_cfg_pin_info[] = {
+ {"gpio@601000_18", "KEY_CONFIG_0"},
+ {"gpio@601000_19", "KEY_CONFIG_1"},
+ {"gpio@601000_88", "KEY_CONFIG_2"},
+ {"gpio@601000_89", "KEY_CONFIG_3"},
+};
+
+static const struct m2_config_table m2_config_table[] = {
+ {{{0, 1, 0, 0}}, BKEY_PCIEX2},
+ {{{0, 0, 1, 0}}, BKEY_PCIE_EKEY_PCIE},
+ {{{0, 1, 1, 0}}, BKEY_PCIE_EKEY_PCIE},
+ {{{1, 0, 0, 1}}, BKEY_PCIE_EKEY_PCIE},
+ {{{1, 1, 0, 1}}, BKEY_PCIE_EKEY_PCIE},
+ {{{0, 0, 0, 1}}, BKEY_USB30_EKEY_PCIE},
+ {{{0, 1, 0, 1}}, BKEY_USB30_EKEY_PCIE},
+ {{{0, 0, 1, 1}}, BKEY_USB30_EKEY_PCIE},
+ {{{0, 1, 1, 1}}, BKEY_USB30_EKEY_PCIE},
+ {{{1, 0, 1, 1}}, BKEY_USB30_EKEY_PCIE},
+};
+
+static const struct serdes_mux_control serdes_mux_ctrl[] = {
+ [BKEY_PCIEX2] = {0, 0, 1},
+ [BKEY_PCIE_EKEY_PCIE] = {0, 1, 0},
+ [BKEY_USB30_EKEY_PCIE] = {1, 1, 0},
+};
+
+static const char *m2_connector_mode_name[] = {
+ [BKEY_PCIEX2] = "PCIe x2 (key B)",
+ [BKEY_PCIE_EKEY_PCIE] = "PCIe (key B) / PCIe (key E)",
+ [BKEY_USB30_EKEY_PCIE] = "USB 3.0 (key B) / PCIe (key E)",
+};
+
+static enum m2_connector_mode connector_mode;
+
+#if defined(CONFIG_OF_LIBFDT) && defined(CONFIG_OF_BOARD_SETUP)
+static void *connector_overlay;
+static u32 connector_overlay_size;
+#endif
+
+static int get_pinvalue(const char *gpio_name, const char *label)
+{
+ struct gpio_desc gpio;
+
+ if (dm_gpio_lookup_name(gpio_name, &gpio) < 0 ||
+ dm_gpio_request(&gpio, label) < 0 ||
+ dm_gpio_set_dir_flags(&gpio, GPIOD_IS_IN) < 0) {
+ pr_err("Cannot get pin %s for M.2 configuration\n", gpio_name);
+ return 0;
+ }
+
+ return dm_gpio_get_value(&gpio);
+}
+
+static void set_pinvalue(const char *gpio_name, const char *label, int value)
+{
+ struct gpio_desc gpio;
+
+ if (dm_gpio_lookup_name(gpio_name, &gpio) < 0 ||
+ dm_gpio_request(&gpio, label) < 0 ||
+ dm_gpio_set_dir_flags(&gpio, GPIOD_IS_OUT) < 0) {
+ pr_err("Cannot set pin %s for M.2 configuration\n", gpio_name);
+ return;
+ }
+ dm_gpio_set_value(&gpio, value);
+}
+
+static bool board_is_m2(void)
+{
+ struct iot2050_info *info = IOT2050_INFO_DATA;
+
+ return IS_ENABLED(CONFIG_TARGET_IOT2050_A53_PG2) &&
+ info->magic == IOT2050_INFO_MAGIC &&
+ strcmp((char *)info->name, "IOT2050-ADVANCED-M2") == 0;
+}
+
static bool board_is_advanced(void)
{
struct iot2050_info *info = IOT2050_INFO_DATA;
@@ -103,6 +213,8 @@
if (board_is_advanced()) {
if (IS_ENABLED(CONFIG_TARGET_IOT2050_A53_PG1))
fdtfile = "ti/k3-am6548-iot2050-advanced.dtb";
+ else if(board_is_m2())
+ fdtfile = "ti/k3-am6548-iot2050-advanced-m2.dtb";
else
fdtfile = "ti/k3-am6548-iot2050-advanced-pg2.dtb";
} else {
@@ -118,6 +230,101 @@
env_save();
}
+static void m2_overlay_prepare(void)
+{
+#if defined(CONFIG_OF_LIBFDT) && defined(CONFIG_OF_BOARD_SETUP)
+ const char *overlay_path;
+ void *overlay;
+ u64 loadaddr;
+ ofnode node;
+ int ret;
+
+ if (connector_mode == BKEY_PCIEX2)
+ return;
+
+ if (connector_mode == BKEY_PCIE_EKEY_PCIE)
+ overlay_path = "/fit-images/bkey-ekey-pcie-overlay";
+ else
+ overlay_path = "/fit-images/bkey-usb3-overlay";
+
+ node = ofnode_path(overlay_path);
+ if (!ofnode_valid(node))
+ goto fit_error;
+
+ ret = ofnode_read_u64(node, "load", &loadaddr);
+ if (ret)
+ goto fit_error;
+
+ ret = ofnode_read_u32(node, "size", &connector_overlay_size);
+ if (ret)
+ goto fit_error;
+
+ overlay = map_sysmem(loadaddr, connector_overlay_size);
+
+ connector_overlay = malloc(connector_overlay_size);
+ if (!connector_overlay)
+ goto fit_error;
+
+ memcpy(connector_overlay, overlay, connector_overlay_size);
+ return;
+
+fit_error:
+ pr_err("M.2 device tree overlay %s not available,\n", overlay_path);
+#endif
+}
+
+static void m2_connector_setup(void)
+{
+ ulong m2_manual_config = env_get_ulong("m2_manual_config", 10,
+ CONNECTOR_MODE_INVALID);
+ const char *mode_info = "";
+ struct m2_config_pins config_pins;
+ unsigned int n;
+
+ /* enable M.2 connector power */
+ set_pinvalue("gpio@601000_17", "P3V3_M2_EN", 1);
+ udelay(4 * 100);
+
+ if (m2_manual_config < CONNECTOR_MODE_INVALID) {
+ mode_info = " [manual mode]";
+ connector_mode = m2_manual_config;
+ } else { /* auto detection */
+ for (n = 0; n < ARRAY_SIZE(config_pins.config); n++)
+ config_pins.config[n] =
+ get_pinvalue(m2_bkey_cfg_pin_info[n].gpio_name,
+ m2_bkey_cfg_pin_info[n].label);
+ connector_mode = CONNECTOR_MODE_INVALID;
+ for (n = 0; n < ARRAY_SIZE(m2_config_table); n++) {
+ if (!memcmp(config_pins.config,
+ m2_config_table[n].config_pins.config,
+ sizeof(config_pins.config))) {
+ connector_mode = m2_config_table[n].mode;
+ break;
+ }
+ }
+ if (connector_mode == CONNECTOR_MODE_INVALID) {
+ mode_info = " [fallback, card unknown/unsupported]";
+ connector_mode = BKEY_USB30_EKEY_PCIE;
+ }
+ }
+
+ printf("M.2: %s%s\n", m2_connector_mode_name[connector_mode],
+ mode_info);
+
+ /* configure serdes mux */
+ set_pinvalue(serdes_mux_ctl_pin_info[0].gpio_name,
+ serdes_mux_ctl_pin_info[0].label,
+ serdes_mux_ctrl[connector_mode].ctrl_usb30_pcie0_lane0);
+ set_pinvalue(serdes_mux_ctl_pin_info[1].gpio_name,
+ serdes_mux_ctl_pin_info[1].label,
+ serdes_mux_ctrl[connector_mode].ctrl_pcie1_pcie0);
+ set_pinvalue(serdes_mux_ctl_pin_info[2].gpio_name,
+ serdes_mux_ctl_pin_info[2].label,
+ serdes_mux_ctrl[connector_mode].ctrl_usb30_pcie0_lane1);
+
+ m2_overlay_prepare();
+}
+
int board_init(void)
{
return 0;
@@ -215,6 +422,9 @@
/* change CTRL_MMR register to let serdes0 not output USB3.0 signals. */
writel(0x3, SERDES0_LANE_SELECT);
+ if (board_is_m2())
+ m2_connector_setup();
+
set_board_info_env();
/* remove the eMMC if requested via button */
@@ -226,6 +436,50 @@
}
#if defined(CONFIG_OF_LIBFDT) && defined(CONFIG_OF_BOARD_SETUP)
+static void m2_fdt_fixup(void *blob)
+{
+ void *overlay_copy = NULL;
+ void *fdt_copy = NULL;
+ u32 fdt_size;
+ int err;
+
+ if (!connector_overlay)
+ return;
+
+ /*
+ * We need to work with temporary copies here because fdt_overlay_apply
+ * is destructive to the overlay and also to the target blob, even if
+ * application fails.
+ */
+ fdt_size = fdt_totalsize(blob);
+ fdt_copy = malloc(fdt_size);
+ if (!fdt_copy)
+ goto fixup_error;
+
+ memcpy(fdt_copy, blob, fdt_size);
+
+ overlay_copy = malloc(connector_overlay_size);
+ if (!overlay_copy)
+ goto fixup_error;
+
+ memcpy(overlay_copy, connector_overlay, connector_overlay_size);
+
+ err = fdt_overlay_apply_verbose(fdt_copy, overlay_copy);
+ if (err)
+ goto fixup_error;
+
+ memcpy(blob, fdt_copy, fdt_size);
+
+cleanup:
+ free(fdt_copy);
+ free(overlay_copy);
+ return;
+
+fixup_error:
+ pr_err("Could not apply M.2 device tree overlay\n");
+ goto cleanup;
+}
+
int ft_board_setup(void *blob, struct bd_info *bd)
{
int ret;
@@ -237,6 +491,9 @@
if (ret)
pr_err("%s: fixing up msmc ram failed %d\n", __func__, ret);
+ if (board_is_m2())
+ m2_fdt_fixup(blob);
+
return ret;
}
#endif