[PATCH v4 2/2] fpga: m10bmc-sec: add m10bmc_sec_retimer_load callback

[Tianfei Zhang <tianfei.zhang@intel.com>]

From: Russ Weight <russell.h.weight@intel.com>

Create m10bmc_sec_retimer_load() callback function
to provide a trigger to update a new retimer (Intel
C827 Ethernet transceiver) firmware on Intel PAC
N3000 Card.

Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Signed-off-by: Tianfei Zhang <tianfei.zhang@intel.com>
---
v3:
uses regmap_update_bits() API instead of m10bmc_sys_update_bits().
---
 drivers/fpga/intel-m10-bmc-sec-update.c | 148 ++++++++++++++++++++++++
 include/linux/mfd/intel-m10-bmc.h       |  31 +++++
 2 files changed, 179 insertions(+)

diff --git a/drivers/fpga/intel-m10-bmc-sec-update.c b/drivers/fpga/intel-m10-bmc-sec-update.c
index 3a082911cf67..bef07e97c107 100644
--- a/drivers/fpga/intel-m10-bmc-sec-update.c
+++ b/drivers/fpga/intel-m10-bmc-sec-update.c
@@ -300,6 +300,150 @@ static int m10bmc_sec_bmc_image_load_1(struct m10bmc_sec *sec)
 	return m10bmc_sec_bmc_image_load(sec, 1);
 }
 
+static int trigger_retimer_eeprom_load(struct m10bmc_sec *sec)
+{
+	struct intel_m10bmc *m10bmc = sec->m10bmc;
+	unsigned int val;
+	int ret;
+
+	ret = regmap_update_bits(m10bmc->regmap,
+				 M10BMC_SYS_BASE + M10BMC_DOORBELL,
+				 DRBL_PKVL_EEPROM_LOAD_SEC,
+				 DRBL_PKVL_EEPROM_LOAD_SEC);
+	if (ret)
+		return ret;
+
+	/*
+	 * If the current NIOS FW supports this retimer update feature, then
+	 * it will clear the same PKVL_EEPROM_LOAD bit in 2 seconds. Otherwise
+	 * the driver needs to clear the PKVL_EEPROM_LOAD bit manually and
+	 * return an error code.
+	 */
+	ret = regmap_read_poll_timeout(m10bmc->regmap,
+				       M10BMC_SYS_BASE + M10BMC_DOORBELL, val,
+				       (!(val & DRBL_PKVL_EEPROM_LOAD_SEC)),
+				       M10BMC_PKVL_LOAD_INTERVAL_US,
+				       M10BMC_PKVL_LOAD_TIMEOUT_US);
+	if (ret == -ETIMEDOUT) {
+		dev_err(sec->dev, "PKVL_EEPROM_LOAD clear timedout\n");
+		regmap_update_bits(m10bmc->regmap,
+				   M10BMC_SYS_BASE + M10BMC_DOORBELL,
+				   DRBL_PKVL_EEPROM_LOAD_SEC, 0);
+		ret = -ENODEV;
+	} else if (ret) {
+		dev_err(sec->dev, "poll EEPROM_LOAD error %d\n", ret);
+	}
+
+	return ret;
+}
+
+static int poll_retimer_eeprom_load_done(struct m10bmc_sec *sec)
+{
+	struct intel_m10bmc *m10bmc = sec->m10bmc;
+	unsigned int doorbell;
+	int ret;
+
+	/*
+	 * RSU_STAT_PKVL_REJECT indicates that the current image is
+	 * already programmed. RSU_PROG_PKVL_PROM_DONE that the firmware
+	 * update process has finished, but does not necessarily indicate
+	 * a successful update.
+	 */
+	ret = regmap_read_poll_timeout(m10bmc->regmap,
+				       M10BMC_SYS_BASE + M10BMC_DOORBELL,
+				       doorbell,
+				       ((rsu_prog(doorbell) ==
+					 RSU_PROG_PKVL_PROM_DONE) ||
+					(rsu_stat(doorbell) ==
+					 RSU_STAT_PKVL_REJECT)),
+				       M10BMC_PKVL_PRELOAD_INTERVAL_US,
+				       M10BMC_PKVL_PRELOAD_TIMEOUT_US);
+	if (ret) {
+		if (ret == -ETIMEDOUT)
+			dev_err(sec->dev,
+				"Doorbell check timedout: 0x%08x\n", doorbell);
+		else
+			dev_err(sec->dev, "poll Doorbell error\n");
+		return ret;
+	}
+
+	if (rsu_stat(doorbell) == RSU_STAT_PKVL_REJECT) {
+		dev_err(sec->dev, "duplicate image rejected\n");
+		return -ECANCELED;
+	}
+
+	return 0;
+}
+
+static int poll_retimer_preload_done(struct m10bmc_sec *sec)
+{
+	struct intel_m10bmc *m10bmc = sec->m10bmc;
+	unsigned int val;
+	int ret;
+
+	/*
+	 * Wait for the updated firmware to be loaded by the PKVL device
+	 * and confirm that the updated firmware is operational
+	 */
+	ret = regmap_read_poll_timeout(m10bmc->regmap,
+				       M10BMC_SYS_BASE + M10BMC_PKVL_POLL_CTRL, val,
+				       ((val & M10BMC_PKVL_PRELOAD) == M10BMC_PKVL_PRELOAD),
+				       M10BMC_PKVL_PRELOAD_INTERVAL_US,
+				       M10BMC_PKVL_PRELOAD_TIMEOUT_US);
+	if (ret) {
+		dev_err(sec->dev, "poll M10BMC_PKVL_PRELOAD error %d\n", ret);
+		return ret;
+	}
+
+	if ((val & M10BMC_PKVL_UPG_STATUS_MASK) != M10BMC_PKVL_UPG_STATUS_GOOD) {
+		dev_err(sec->dev, "error detected during upgrade\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int retimer_check_idle(struct m10bmc_sec *sec)
+{
+	u32 doorbell;
+	int ret;
+
+	ret = m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell);
+	if (ret)
+		return -EIO;
+
+	if (rsu_prog(doorbell) != RSU_PROG_IDLE &&
+	    rsu_prog(doorbell) != RSU_PROG_RSU_DONE &&
+	    rsu_prog(doorbell) != RSU_PROG_PKVL_PROM_DONE) {
+		log_error_regs(sec, doorbell);
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
+static int m10bmc_sec_retimer_eeprom_load(struct m10bmc_sec *sec)
+{
+	int ret;
+
+	ret = retimer_check_idle(sec);
+	if (ret)
+		goto exit;
+
+	ret = trigger_retimer_eeprom_load(sec);
+	if (ret)
+		goto exit;
+
+	ret = poll_retimer_eeprom_load_done(sec);
+	if (ret)
+		goto exit;
+
+	ret = poll_retimer_preload_done(sec);
+
+exit:
+	return ret;
+}
+
 static struct image_load m10bmc_image_load_hndlrs[] = {
 	{
 		.name = "bmc_factory",
@@ -309,6 +453,10 @@ static struct image_load m10bmc_image_load_hndlrs[] = {
 		.name = "bmc_user",
 		.load_image = m10bmc_sec_bmc_image_load_0,
 	},
+	{
+		.name = "retimer_fw",
+		.load_image = m10bmc_sec_retimer_eeprom_load,
+	},
 	{}
 };
 
diff --git a/include/linux/mfd/intel-m10-bmc.h b/include/linux/mfd/intel-m10-bmc.h
index f0044b14136e..c06b9d3d1c5d 100644
--- a/include/linux/mfd/intel-m10-bmc.h
+++ b/include/linux/mfd/intel-m10-bmc.h
@@ -36,6 +36,37 @@
 #define M10BMC_VER_PCB_INFO_MSK		GENMASK(31, 24)
 #define M10BMC_VER_LEGACY_INVALID	0xffffffff
 
+/* Retimer related registers, in system register region */
+#define M10BMC_PKVL_POLL_CTRL		0x80
+#define M10BMC_PKVL_A_PRELOAD		BIT(16)
+#define M10BMC_PKVL_A_PRELOAD_TO	BIT(17)
+#define M10BMC_PKVL_A_DATA_TOO_BIG	BIT(18)
+#define M10BMC_PKVL_A_HDR_CKSUM	BIT(20)
+#define M10BMC_PKVL_B_PRELOAD		BIT(24)
+#define M10BMC_PKVL_B_PRELOAD_TO	BIT(25)
+#define M10BMC_PKVL_B_DATA_TOO_BIG	BIT(26)
+#define M10BMC_PKVL_B_HDR_CKSUM	BIT(28)
+
+#define M10BMC_PKVL_PRELOAD		(M10BMC_PKVL_A_PRELOAD | M10BMC_PKVL_B_PRELOAD)
+#define M10BMC_PKVL_PRELOAD_TIMEOUT	(M10BMC_PKVL_A_PRELOAD_TO | \
+					 M10BMC_PKVL_B_PRELOAD_TO)
+#define M10BMC_PKVL_DATA_TOO_BIG	(M10BMC_PKVL_A_DATA_TOO_BIG | \
+					 M10BMC_PKVL_B_DATA_TOO_BIG)
+#define M10BMC_PKVL_HDR_CHECKSUM	(M10BMC_PKVL_A_HDR_CKSUM | \
+					 M10BMC_PKVL_B_HDR_CKSUM)
+
+#define M10BMC_PKVL_UPG_STATUS_MASK	(M10BMC_PKVL_PRELOAD | M10BMC_PKVL_PRELOAD_TIMEOUT |\
+					 M10BMC_PKVL_DATA_TOO_BIG | M10BMC_PKVL_HDR_CHECKSUM)
+#define M10BMC_PKVL_UPG_STATUS_GOOD	(M10BMC_PKVL_PRELOAD | M10BMC_PKVL_HDR_CHECKSUM)
+
+/* interval 100ms and timeout 2s */
+#define M10BMC_PKVL_LOAD_INTERVAL_US	(100 * 1000)
+#define M10BMC_PKVL_LOAD_TIMEOUT_US	(2 * 1000 * 1000)
+
+/* interval 100ms and timeout 30s */
+#define M10BMC_PKVL_PRELOAD_INTERVAL_US	(100 * 1000)
+#define M10BMC_PKVL_PRELOAD_TIMEOUT_US	(30 * 1000 * 1000)
+
 /* Secure update doorbell register, in system register region */
 #define M10BMC_DOORBELL			0x400
 
-- 
2.26.2