@@ -6,23 +6,326 @@
* Author: Fabrice Gasnier <fabrice.gasnier@foss.st.com>.
*/
+#include <linux/delay.h>
+#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/platform_device.h>
+#include <asm/unaligned.h>
#include "ucsi.h"
+/* STM32G0 I2C bootloader addr: 0b1010001x (See AN2606) */
+#define STM32G0_I2C_BL_ADDR (0xa2 >> 1)
+
+/* STM32G0 I2C bootloader max data size */
+#define STM32G0_I2C_BL_SZ 256
+
+/* STM32 I2C bootloader commands (See AN4221) */
+#define STM32_CMD_GVR 0x01 /* Gets the bootloader version */
+#define STM32_CMD_GVR_LEN 1
+#define STM32_CMD_RM 0x11 /* Reag memory */
+#define STM32_CMD_WM 0x31 /* Write memory */
+#define STM32_CMD_ADDR_LEN 5 /* Address len for go, mem write... */
+#define STM32_CMD_ERASE 0x44 /* Erase page, bank or all */
+#define STM32_CMD_ERASE_SPECIAL_LEN 3
+#define STM32_CMD_GLOBAL_MASS_ERASE 0xffff /* All-bank erase */
+
+/* STM32 I2C bootloader answer status */
+#define STM32G0_I2C_BL_ACK 0x79
+#define STM32G0_I2C_BL_NACK 0x1f
+#define STM32G0_I2C_BL_BUSY 0x76
+
+/* STM32G0 flash definitions */
+#define STM32G0_USER_OPTION_BYTES 0x1fff7800
+#define STM32G0_USER_OB_NBOOT0 BIT(26)
+#define STM32G0_USER_OB_NBOOT_SEL BIT(24)
+#define STM32G0_USER_OB_BOOT_MAIN (STM32G0_USER_OB_NBOOT0 | STM32G0_USER_OB_NBOOT_SEL)
+#define STM32G0_MAIN_MEM_ADDR 0x08000000
+
+/* STM32 Firmware definitions: additional commands */
+#define STM32G0_FW_GETVER 0x00 /* Gets the firmware version */
+#define STM32G0_FW_GETVER_LEN 4
+#define STM32G0_FW_RSTGOBL 0x21 /* Reset and go to bootloader */
+#define STM32G0_FW_KEYWORD 0xa56959a6
+
+/* ucsi_stm32g0_fw_info located at the end of the firmware */
+struct ucsi_stm32g0_fw_info {
+ u32 version;
+ u32 keyword;
+};
+
struct ucsi_stm32g0 {
struct i2c_client *client;
+ struct i2c_client *i2c_bl;
+ bool in_bootloader;
+ u8 bl_version;
struct completion complete;
struct device *dev;
unsigned long flags;
+ const char *fw_name;
struct ucsi *ucsi;
bool suspended;
bool wakeup_event;
};
+/*
+ * Bootloader commands helpers:
+ * - send command (2 bytes)
+ * - check ack
+ * Then either:
+ * - receive data
+ * - receive data + check ack
+ * - send data + check ack
+ * These operations depends on the command and have various length.
+ */
+static int ucsi_stm32g0_bl_check_ack(struct ucsi *ucsi)
+{
+ struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
+ struct i2c_client *client = g0->i2c_bl;
+ unsigned char ack;
+ struct i2c_msg msg[] = {
+ {
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .len = 1,
+ .buf = &ack,
+ },
+ };
+ int ret;
+
+ ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+ if (ret != ARRAY_SIZE(msg)) {
+ dev_err(g0->dev, "i2c bl ack (%02x), error: %d\n", client->addr, ret);
+
+ return ret < 0 ? ret : -EIO;
+ }
+
+ /* The 'ack' byte should contain bootloader answer: ack/nack/busy */
+ switch (ack) {
+ case STM32G0_I2C_BL_ACK:
+ return 0;
+ case STM32G0_I2C_BL_NACK:
+ return -ENOENT;
+ case STM32G0_I2C_BL_BUSY:
+ return -EBUSY;
+ default:
+ dev_err(g0->dev, "i2c bl ack (%02x), invalid byte: %02x\n",
+ client->addr, ack);
+ return -EINVAL;
+ }
+}
+
+static int ucsi_stm32g0_bl_cmd_check_ack(struct ucsi *ucsi, unsigned int cmd, bool check_ack)
+{
+ struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
+ struct i2c_client *client = g0->i2c_bl;
+ unsigned char buf[2];
+ struct i2c_msg msg[] = {
+ {
+ .addr = client->addr,
+ .flags = 0,
+ .len = sizeof(buf),
+ .buf = buf,
+ },
+ };
+ int ret;
+
+ /*
+ * Send STM32 bootloader command format is two bytes:
+ * - command code
+ * - XOR'ed command code
+ */
+ buf[0] = cmd;
+ buf[1] = cmd ^ 0xff;
+
+ ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+ if (ret != ARRAY_SIZE(msg)) {
+ dev_dbg(g0->dev, "i2c bl cmd %d (%02x), error: %d\n", cmd, client->addr, ret);
+
+ return ret < 0 ? ret : -EIO;
+ }
+
+ if (check_ack)
+ return ucsi_stm32g0_bl_check_ack(ucsi);
+
+ return 0;
+}
+
+static int ucsi_stm32g0_bl_cmd(struct ucsi *ucsi, unsigned int cmd)
+{
+ return ucsi_stm32g0_bl_cmd_check_ack(ucsi, cmd, true);
+}
+
+static int ucsi_stm32g0_bl_rcv_check_ack(struct ucsi *ucsi, void *data, size_t len, bool check_ack)
+{
+ struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
+ struct i2c_client *client = g0->i2c_bl;
+ struct i2c_msg msg[] = {
+ {
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .len = len,
+ .buf = data,
+ },
+ };
+ int ret;
+
+ ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+ if (ret != ARRAY_SIZE(msg)) {
+ dev_err(g0->dev, "i2c bl rcv %02x, error: %d\n", client->addr, ret);
+
+ return ret < 0 ? ret : -EIO;
+ }
+
+ if (check_ack)
+ return ucsi_stm32g0_bl_check_ack(ucsi);
+
+ return 0;
+}
+
+static int ucsi_stm32g0_bl_rcv(struct ucsi *ucsi, void *data, size_t len)
+{
+ return ucsi_stm32g0_bl_rcv_check_ack(ucsi, data, len, true);
+}
+
+static int ucsi_stm32g0_bl_rcv_woack(struct ucsi *ucsi, void *data, size_t len)
+{
+ return ucsi_stm32g0_bl_rcv_check_ack(ucsi, data, len, false);
+}
+
+static int ucsi_stm32g0_bl_send(struct ucsi *ucsi, void *data, size_t len)
+{
+ struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
+ struct i2c_client *client = g0->i2c_bl;
+ struct i2c_msg msg[] = {
+ {
+ .addr = client->addr,
+ .flags = 0,
+ .len = len,
+ .buf = data,
+ },
+ };
+ int ret;
+
+ ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
+ if (ret != ARRAY_SIZE(msg)) {
+ dev_err(g0->dev, "i2c bl send %02x, error: %d\n", client->addr, ret);
+
+ return ret < 0 ? ret : -EIO;
+ }
+
+ return ucsi_stm32g0_bl_check_ack(ucsi);
+}
+
+/* Bootloader commands */
+static int ucsi_stm32g0_bl_get_version(struct ucsi *ucsi, u8 *bl_version)
+{
+ int ret;
+
+ ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_GVR);
+ if (ret)
+ return ret;
+
+ return ucsi_stm32g0_bl_rcv(ucsi, bl_version, STM32_CMD_GVR_LEN);
+}
+
+static int ucsi_stm32g0_bl_send_addr(struct ucsi *ucsi, u32 addr)
+{
+ u8 data8[STM32_CMD_ADDR_LEN];
+
+ /* Address format: 4 bytes addr (MSB first) + XOR'ed addr bytes */
+ put_unaligned_be32(addr, data8);
+ data8[4] = data8[0] ^ data8[1] ^ data8[2] ^ data8[3];
+
+ return ucsi_stm32g0_bl_send(ucsi, data8, STM32_CMD_ADDR_LEN);
+}
+
+static int ucsi_stm32g0_bl_global_mass_erase(struct ucsi *ucsi)
+{
+ u8 data8[4];
+ u16 *data16 = (u16 *)&data8[0];
+ int ret;
+
+ data16[0] = STM32_CMD_GLOBAL_MASS_ERASE;
+ data8[2] = data8[0] ^ data8[1];
+
+ ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_ERASE);
+ if (ret)
+ return ret;
+
+ return ucsi_stm32g0_bl_send(ucsi, data8, STM32_CMD_ERASE_SPECIAL_LEN);
+}
+
+static int ucsi_stm32g0_bl_write(struct ucsi *ucsi, u32 addr, const void *data, size_t len)
+{
+ u8 *data8;
+ int i, ret;
+
+ if (!len || len > STM32G0_I2C_BL_SZ)
+ return -EINVAL;
+
+ /* Write memory: len bytes -1, data up to 256 bytes + XOR'ed bytes */
+ data8 = kmalloc(STM32G0_I2C_BL_SZ + 2, GFP_KERNEL);
+ if (!data8)
+ return -ENOMEM;
+
+ ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_WM);
+ if (ret)
+ goto free;
+
+ ret = ucsi_stm32g0_bl_send_addr(ucsi, addr);
+ if (ret)
+ goto free;
+
+ data8[0] = len - 1;
+ memcpy(data8 + 1, data, len);
+ data8[len + 1] = data8[0];
+ for (i = 1; i <= len; i++)
+ data8[len + 1] ^= data8[i];
+
+ ret = ucsi_stm32g0_bl_send(ucsi, data8, len + 2);
+free:
+ kfree(data8);
+
+ return ret;
+}
+
+static int ucsi_stm32g0_bl_read(struct ucsi *ucsi, u32 addr, void *data, size_t len)
+{
+ int ret;
+
+ if (!len || len > STM32G0_I2C_BL_SZ)
+ return -EINVAL;
+
+ ret = ucsi_stm32g0_bl_cmd(ucsi, STM32_CMD_RM);
+ if (ret)
+ return ret;
+
+ ret = ucsi_stm32g0_bl_send_addr(ucsi, addr);
+ if (ret)
+ return ret;
+
+ ret = ucsi_stm32g0_bl_cmd(ucsi, len - 1);
+ if (ret)
+ return ret;
+
+ return ucsi_stm32g0_bl_rcv_woack(ucsi, data, len);
+}
+
+/* Firmware commands (the same address as the bootloader) */
+static int ucsi_stm32g0_fw_cmd(struct ucsi *ucsi, unsigned int cmd)
+{
+ return ucsi_stm32g0_bl_cmd_check_ack(ucsi, cmd, false);
+}
+
+static int ucsi_stm32g0_fw_rcv(struct ucsi *ucsi, void *data, size_t len)
+{
+ return ucsi_stm32g0_bl_rcv_woack(ucsi, data, len);
+}
+
+/* UCSI ops */
static int ucsi_stm32g0_read(struct ucsi *ucsi, unsigned int offset, void *val, size_t len)
{
struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
@@ -138,6 +441,191 @@ static const struct ucsi_operations ucsi_stm32g0_ops = {
.async_write = ucsi_stm32g0_async_write,
};
+static int ucsi_stm32g0_register(struct ucsi *ucsi)
+{
+ struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
+ struct i2c_client *client = g0->client;
+ int ret;
+
+ /* Request alert interrupt */
+ ret = request_threaded_irq(client->irq, NULL, ucsi_stm32g0_irq_handler, IRQF_ONESHOT,
+ dev_name(g0->dev), g0);
+ if (ret) {
+ dev_err(g0->dev, "request IRQ failed: %d\n", ret);
+ return ret;
+ }
+
+ ret = ucsi_register(ucsi);
+ if (ret) {
+ dev_err_probe(g0->dev, ret, "ucsi_register failed\n");
+ free_irq(client->irq, g0);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void ucsi_stm32g0_unregister(struct ucsi *ucsi)
+{
+ struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
+ struct i2c_client *client = g0->client;
+
+ ucsi_unregister(ucsi);
+ free_irq(client->irq, g0);
+}
+
+static void ucsi_stm32g0_fw_cb(const struct firmware *fw, void *context)
+{
+ struct ucsi_stm32g0 *g0;
+ const u8 *data, *end;
+ const struct ucsi_stm32g0_fw_info *fw_info;
+ u32 addr = STM32G0_MAIN_MEM_ADDR, ob, fw_version;
+ int ret, size;
+
+ if (!context)
+ return;
+
+ g0 = ucsi_get_drvdata(context);
+
+ if (!fw)
+ goto fw_release;
+
+ fw_info = (struct ucsi_stm32g0_fw_info *)(fw->data + fw->size - sizeof(*fw_info));
+
+ if (!g0->in_bootloader) {
+ /* Read running firmware version */
+ ret = ucsi_stm32g0_fw_cmd(g0->ucsi, STM32G0_FW_GETVER);
+ if (ret) {
+ dev_err(g0->dev, "Get version cmd failed %d\n", ret);
+ goto fw_release;
+ }
+ ret = ucsi_stm32g0_fw_rcv(g0->ucsi, &fw_version,
+ STM32G0_FW_GETVER_LEN);
+ if (ret) {
+ dev_err(g0->dev, "Get version failed %d\n", ret);
+ goto fw_release;
+ }
+
+ /* Sanity check on keyword and firmware version */
+ if (fw_info->keyword != STM32G0_FW_KEYWORD || fw_info->version == fw_version)
+ goto fw_release;
+
+ dev_info(g0->dev, "Flashing FW: %08x (%08x cur)\n", fw_info->version, fw_version);
+
+ /* Switch to bootloader mode */
+ ucsi_stm32g0_unregister(g0->ucsi);
+ ret = ucsi_stm32g0_fw_cmd(g0->ucsi, STM32G0_FW_RSTGOBL);
+ if (ret) {
+ dev_err(g0->dev, "bootloader cmd failed %d\n", ret);
+ goto fw_release;
+ }
+ g0->in_bootloader = true;
+
+ /* STM32G0 reboot delay */
+ msleep(100);
+ }
+
+ ret = ucsi_stm32g0_bl_global_mass_erase(g0->ucsi);
+ if (ret) {
+ dev_err(g0->dev, "Erase failed %d\n", ret);
+ goto fw_release;
+ }
+
+ data = fw->data;
+ end = fw->data + fw->size;
+ while (data < end) {
+ if ((end - data) < STM32G0_I2C_BL_SZ)
+ size = end - data;
+ else
+ size = STM32G0_I2C_BL_SZ;
+
+ ret = ucsi_stm32g0_bl_write(g0->ucsi, addr, data, size);
+ if (ret) {
+ dev_err(g0->dev, "Write failed %d\n", ret);
+ goto fw_release;
+ }
+ addr += size;
+ data += size;
+ }
+
+ dev_dbg(g0->dev, "Configure to boot from main flash\n");
+
+ ret = ucsi_stm32g0_bl_read(g0->ucsi, STM32G0_USER_OPTION_BYTES, &ob, sizeof(ob));
+ if (ret) {
+ dev_err(g0->dev, "read user option bytes failed %d\n", ret);
+ goto fw_release;
+ }
+
+ dev_dbg(g0->dev, "STM32G0_USER_OPTION_BYTES 0x%08x\n", ob);
+
+ /* Configure user option bytes to boot from main flash next time */
+ ob |= STM32G0_USER_OB_BOOT_MAIN;
+
+ /* Writing option bytes will also reset G0 for updates to be loaded */
+ ret = ucsi_stm32g0_bl_write(g0->ucsi, STM32G0_USER_OPTION_BYTES, &ob, sizeof(ob));
+ if (ret) {
+ dev_err(g0->dev, "write user option bytes failed %d\n", ret);
+ goto fw_release;
+ }
+
+ dev_info(g0->dev, "Starting, option bytes:0x%08x\n", ob);
+
+ /* STM32G0 FW boot delay */
+ msleep(500);
+
+ /* Register UCSI interface */
+ if (!ucsi_stm32g0_register(g0->ucsi))
+ g0->in_bootloader = false;
+
+fw_release:
+ release_firmware(fw);
+}
+
+static int ucsi_stm32g0_probe_bootloader(struct ucsi *ucsi)
+{
+ struct ucsi_stm32g0 *g0 = ucsi_get_drvdata(ucsi);
+ int ret;
+ u16 ucsi_version;
+
+ /* firmware-name is optional */
+ if (device_property_present(g0->dev, "firmware-name")) {
+ ret = device_property_read_string(g0->dev, "firmware-name", &g0->fw_name);
+ if (ret < 0)
+ return dev_err_probe(g0->dev, ret, "Error reading firmware-name\n");
+ }
+
+ if (g0->fw_name) {
+ /* STM32G0 in bootloader mode communicates at reserved address 0x51 */
+ g0->i2c_bl = i2c_new_dummy_device(g0->client->adapter, STM32G0_I2C_BL_ADDR);
+ if (IS_ERR(g0->i2c_bl)) {
+ ret = dev_err_probe(g0->dev, PTR_ERR(g0->i2c_bl),
+ "Failed to register booloader I2C address\n");
+ return ret;
+ }
+ }
+
+ /*
+ * Try to guess if the STM32G0 is running a UCSI firmware. First probe the UCSI FW at its
+ * i2c address. Fallback to bootloader i2c address only if firmware-name is specified.
+ */
+ ret = ucsi_stm32g0_read(ucsi, UCSI_VERSION, &ucsi_version, sizeof(ucsi_version));
+ if (!ret || !g0->fw_name)
+ return ret;
+
+ /* Speculatively read the bootloader version that has a known length. */
+ ret = ucsi_stm32g0_bl_get_version(ucsi, &g0->bl_version);
+ if (ret < 0) {
+ i2c_unregister_device(g0->i2c_bl);
+ return ret;
+ }
+
+ /* Device in bootloader mode */
+ g0->in_bootloader = true;
+ dev_info(g0->dev, "Bootloader Version 0x%02x\n", g0->bl_version);
+
+ return 0;
+}
+
static int ucsi_stm32g0_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
@@ -159,24 +647,41 @@ static int ucsi_stm32g0_probe(struct i2c_client *client, const struct i2c_device
ucsi_set_drvdata(g0->ucsi, g0);
- /* Request alert interrupt */
- ret = request_threaded_irq(client->irq, NULL, ucsi_stm32g0_irq_handler, IRQF_ONESHOT,
- dev_name(&client->dev), g0);
- if (ret) {
- dev_err_probe(dev, ret, "request IRQ failed\n");
+ ret = ucsi_stm32g0_probe_bootloader(g0->ucsi);
+ if (ret < 0)
goto destroy;
+
+ /*
+ * Don't register in bootloader mode: wait for the firmware to be loaded and started before
+ * registering UCSI device.
+ */
+ if (!g0->in_bootloader) {
+ ret = ucsi_stm32g0_register(g0->ucsi);
+ if (ret < 0)
+ goto freei2c;
}
- ret = ucsi_register(g0->ucsi);
- if (ret) {
- dev_err_probe(dev, ret, "ucsi_register failed\n");
- goto freeirq;
+ if (g0->fw_name) {
+ /*
+ * Asynchronously flash (e.g. bootloader mode) or update the running firmware,
+ * not to hang the boot process
+ */
+ ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_UEVENT, g0->fw_name, g0->dev,
+ GFP_KERNEL, g0->ucsi, ucsi_stm32g0_fw_cb);
+ if (ret < 0) {
+ dev_err_probe(dev, ret, "firmware request failed\n");
+ goto unregister;
+ }
}
return 0;
-freeirq:
- free_irq(client->irq, g0);
+unregister:
+ if (!g0->in_bootloader)
+ ucsi_stm32g0_unregister(g0->ucsi);
+freei2c:
+ if (g0->fw_name)
+ i2c_unregister_device(g0->i2c_bl);
destroy:
ucsi_destroy(g0->ucsi);
@@ -187,8 +692,10 @@ static int ucsi_stm32g0_remove(struct i2c_client *client)
{
struct ucsi_stm32g0 *g0 = i2c_get_clientdata(client);
- ucsi_unregister(g0->ucsi);
- free_irq(client->irq, g0);
+ if (!g0->in_bootloader)
+ ucsi_stm32g0_unregister(g0->ucsi);
+ if (g0->fw_name)
+ i2c_unregister_device(g0->i2c_bl);
ucsi_destroy(g0->ucsi);
return 0;
@@ -199,6 +706,9 @@ static int ucsi_stm32g0_suspend(struct device *dev)
struct ucsi_stm32g0 *g0 = dev_get_drvdata(dev);
struct i2c_client *client = g0->client;
+ if (g0->in_bootloader)
+ return 0;
+
/* Keep the interrupt disabled until the i2c bus has been resumed */
disable_irq(client->irq);
@@ -216,6 +726,9 @@ static int ucsi_stm32g0_resume(struct device *dev)
struct ucsi_stm32g0 *g0 = dev_get_drvdata(dev);
struct i2c_client *client = g0->client;
+ if (g0->in_bootloader)
+ return 0;
+
if (device_may_wakeup(dev) || device_wakeup_path(dev))
disable_irq_wake(client->irq);