[PATCH 2/3] common: board: phytec: import SoM detection for imx8m based SoM from u-boot

[Marc Kleine-Budde <mkl@pengutronix.de>]

This patch imports and cleans up the SoM detection for imx8n based SoM
from u-boot.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 common/boards/Kconfig                             |   7 +
 common/boards/Makefile                            |   1 +
 common/boards/phytec/Makefile                     |   4 +
 common/boards/phytec/phytec-som-detection.c       | 209 ++++++++++++++++++++++
 common/boards/phytec/phytec-som-imx8m-detection.c | 151 ++++++++++++++++
 include/phytec-som-detection.h                    |  69 +++++++
 include/phytec-som-imx8m-detection.h              |  19 ++
 7 files changed, 460 insertions(+)

diff --git a/common/boards/Kconfig b/common/boards/Kconfig
index e27273b7671d..b240548b484d 100644
--- a/common/boards/Kconfig
+++ b/common/boards/Kconfig
@@ -2,3 +2,10 @@
 
 config BOARD_QEMU_VIRT
 	bool
+
+config BOARD_PHYTEC_SOM_DETECTION
+	bool
+
+config BOARD_PHYTEC_SOM_IMX8M_DETECTION
+	bool
+	select BOARD_PHYTEC_SOM_DETECTION
diff --git a/common/boards/Makefile b/common/boards/Makefile
index 5b4e429c13e9..2a96ce6aec5c 100644
--- a/common/boards/Makefile
+++ b/common/boards/Makefile
@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
 obj-$(CONFIG_BOARD_QEMU_VIRT)	+= qemu-virt/
+obj-y += phytec/
diff --git a/common/boards/phytec/Makefile b/common/boards/phytec/Makefile
new file mode 100644
index 000000000000..741a0e2eb704
--- /dev/null
+++ b/common/boards/phytec/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+lwl-$(CONFIG_BOARD_PHYTEC_SOM_DETECTION) += phytec-som-detection.o
+lwl-$(CONFIG_BOARD_PHYTEC_SOM_IMX8M_DETECTION) += phytec-som-imx8m-detection.o
diff --git a/common/boards/phytec/phytec-som-detection.c b/common/boards/phytec/phytec-som-detection.c
new file mode 100644
index 000000000000..d9479f8ced69
--- /dev/null
+++ b/common/boards/phytec/phytec-som-detection.c
@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 PHYTEC Messtechnik GmbH
+ * Author: Teresa Remmet <t.remmet@phytec.de>
+ */
+
+#include <common.h>
+#include <pbl/eeprom.h>
+#include <phytec-som-imx8m-detection.h>
+
+struct phytec_eeprom_data eeprom_data;
+
+#define POLY (0x1070U << 3)
+
+static u8 _crc8(u16 data)
+{
+	int i;
+
+	for (i = 0; i < 8; i++) {
+		if (data & 0x8000)
+			data = data ^ POLY;
+		data = data << 1;
+	}
+
+	return data >> 8;
+}
+
+static unsigned int crc8(unsigned int crc, const u8 *vptr, int len)
+{
+	int i;
+
+	for (i = 0; i < len; i++)
+		crc = _crc8((crc ^ vptr[i]) << 8);
+
+	return crc;
+}
+
+char *phytec_get_opt(struct phytec_eeprom_data *data)
+{
+	char *opt;
+
+	if (!data)
+		data = &eeprom_data;
+
+	switch (data->api_rev) {
+	case PHYTEC_API_REV0:
+	case PHYTEC_API_REV1:
+		opt = data->data.data_api0.opt;
+		break;
+	case PHYTEC_API_REV2:
+		opt = data->data.data_api2.opt;
+		break;
+	default:
+		opt = NULL;
+		break;
+	};
+
+	return opt;
+}
+
+static int phytec_eeprom_data_init(struct pbl_i2c *i2c,
+				   struct phytec_eeprom_data *data,
+				   int addr, u8 phytec_som_type)
+{
+	unsigned int crc;
+	char *opt;
+	int *ptr;
+	int ret = -1, i;
+	u8 som;
+
+	if (!data)
+		data = &eeprom_data;
+
+	eeprom_read(i2c, addr, I2C_ADDR_16_BIT, data, sizeof(struct phytec_eeprom_data));
+
+	if (data->api_rev == 0xff) {
+		pr_err("%s: EEPROM is not flashed. Prototype?\n", __func__);
+		return -EINVAL;
+	}
+
+	for (i = 0, ptr = (int *)data;
+	     i < sizeof(struct phytec_eeprom_data);
+	     i += sizeof(ptr), ptr++)
+		if (*ptr != 0x0)
+			break;
+
+	if (i == sizeof(struct phytec_eeprom_data)) {
+		pr_err("%s: EEPROM data is all zero. Erased?\n", __func__);
+		return -EINVAL;
+	}
+
+	if (data->api_rev > PHYTEC_API_REV2) {
+		pr_err("%s: EEPROM API revision %u not supported\n",
+		       __func__, data->api_rev);
+		return -EINVAL;
+	}
+
+	/* We are done here for early revisions */
+	if (data->api_rev <= PHYTEC_API_REV1)
+		return 0;
+
+	crc = crc8(0, (const unsigned char *)data,
+		   sizeof(struct phytec_eeprom_data));
+	pr_debug("%s: crc: %x\n", __func__, crc);
+
+	if (crc) {
+		pr_err("%s: CRC mismatch. EEPROM data is not usable\n", __func__);
+		return -EINVAL;
+	}
+
+	som = data->data.data_api2.som_no;
+	pr_debug("%s: som id: %u\n", __func__, som);
+	opt = phytec_get_opt(data);
+	if (!opt)
+		return -EINVAL;
+
+	if (IS_ENABLED(CONFIG_BOARD_PHYTEC_SOM_IMX8M_DETECTION))
+		ret = phytec_imx8m_detect(som, opt, phytec_som_type);
+
+	if (ret) {
+		pr_err("%s: SoM ID does not match. Wrong EEPROM data?\n", __func__);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+void phytec_print_som_info(struct phytec_eeprom_data *data)
+{
+	struct phytec_api2_data *api2;
+	char pcb_sub_rev;
+	unsigned int ksp_no, sub_som_type1 = -1, sub_som_type2 = -1;
+
+	if (!data)
+		data = &eeprom_data;
+
+	if (data->api_rev < PHYTEC_API_REV2)
+		return;
+
+	api2 = &data->data.data_api2;
+
+	/* Calculate PCB subrevision */
+	pcb_sub_rev = api2->pcb_sub_opt_rev & 0x0f;
+	pcb_sub_rev = pcb_sub_rev ? ((pcb_sub_rev - 1) + 'a') : ' ';
+
+	/* print standard product string */
+	if (api2->som_type <= 1) {
+		pr_info("SoM: %s-%03u-%s.%s PCB rev: %u%c\n",
+			phytec_som_type_str[api2->som_type], api2->som_no,
+			api2->opt, api2->bom_rev, api2->pcb_rev, pcb_sub_rev);
+		return;
+	}
+	/* print KSP/KSM string */
+	if (api2->som_type <= 3) {
+		ksp_no = (api2->ksp_no << 8) | api2->som_no;
+		pr_info("SoM: %s-%u ",
+			phytec_som_type_str[api2->som_type], ksp_no);
+		/* print standard product based KSP/KSM strings */
+	} else {
+		switch (api2->som_type) {
+		case 4:
+			sub_som_type1 = 0;
+			sub_som_type2 = 3;
+			break;
+		case 5:
+			sub_som_type1 = 0;
+			sub_som_type2 = 2;
+			break;
+		case 6:
+			sub_som_type1 = 1;
+			sub_som_type2 = 3;
+			break;
+		case 7:
+			sub_som_type1 = 1;
+			sub_som_type2 = 2;
+			break;
+		default:
+			break;
+		};
+
+		pr_info("SoM: %s-%03u-%s-%03u ",
+			phytec_som_type_str[sub_som_type1],
+			api2->som_no, phytec_som_type_str[sub_som_type2],
+			api2->ksp_no);
+	}
+
+	pr_cont("Option: %s BOM rev: %s PCB rev: %u%c\n", api2->opt,
+		api2->bom_rev, api2->pcb_rev, pcb_sub_rev);
+}
+
+int phytec_eeprom_data_setup(struct pbl_i2c *i2c, struct phytec_eeprom_data *data,
+			     int addr, int addr_fallback, u8 cpu_type)
+{
+	int ret;
+
+	ret = phytec_eeprom_data_init(i2c, data, addr, cpu_type);
+	if (ret) {
+		pr_err("%s: init failed. Trying fall back address 0x%x\n",
+		       __func__, addr_fallback);
+		ret = phytec_eeprom_data_init(i2c, data, addr_fallback, cpu_type);
+	}
+
+	if (ret)
+		pr_err("%s: EEPROM data init failed\n", __func__);
+	else
+		pr_debug("%s: init successful\n", __func__);
+
+	return ret;
+}
diff --git a/common/boards/phytec/phytec-som-imx8m-detection.c b/common/boards/phytec/phytec-som-imx8m-detection.c
new file mode 100644
index 000000000000..cc7fb6971548
--- /dev/null
+++ b/common/boards/phytec/phytec-som-imx8m-detection.c
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2020 PHYTEC Messtechnik GmbH
+ * Author: Teresa Remmet <t.remmet@phytec.de>
+ */
+
+#include <common.h>
+#include <mach/imx/generic.h>
+#include <phytec-som-imx8m-detection.h>
+
+extern struct phytec_eeprom_data eeprom_data;
+
+/* Check if the SoM is actually one of the following products:
+ * - i.MX8MM
+ * - i.MX8MN
+ * - i.MX8MP
+ * - i.MX8MQ
+ *
+ * Returns 0 in case it's a known SoM. Otherwise, returns -errno.
+ */
+u8 phytec_imx8m_detect(u8 som, char *opt, u8 cpu_type)
+{
+	if (som == PHYTEC_IMX8MP_SOM && cpu_type == IMX_CPU_IMX8MP)
+		return 0;
+
+	if (som == PHYTEC_IMX8MM_SOM) {
+		if (((opt[0] - '0') != 0) &&
+		    ((opt[1] - '0') == 0) && cpu_type == IMX_CPU_IMX8MM)
+			return 0;
+		else if (((opt[0] - '0') == 0) &&
+			 ((opt[1] - '0') != 0) && cpu_type == IMX_CPU_IMX8MN)
+			return 0;
+		return -EINVAL;
+	}
+
+	if (som == PHYTEC_IMX8MQ_SOM && cpu_type == IMX_CPU_IMX8MQ)
+		return 0;
+
+	return -EINVAL;
+}
+
+/*
+ * So far all PHYTEC i.MX8M boards have RAM size definition at the
+ * same location.
+ */
+u8 phytec_get_imx8m_ddr_size(struct phytec_eeprom_data *data)
+{
+	char *opt;
+	u8 ddr_id;
+
+	if (!data)
+		data = &eeprom_data;
+
+	opt = phytec_get_opt(data);
+	if (opt)
+		ddr_id = opt[2] - '0';
+	else
+		ddr_id = PHYTEC_EEPROM_INVAL;
+
+	pr_debug("%s: ddr id: %u\n", __func__, ddr_id);
+
+	return ddr_id;
+}
+
+/*
+ * Filter SPI-NOR flash information. All i.MX8M boards have this at
+ * the same location.
+ * returns: 0x0 if no SPI is poulated. Otherwise a board depended
+ * code for the size. PHYTEC_EEPROM_INVAL when the data is invalid.
+ */
+u8 phytec_get_imx8m_spi(struct phytec_eeprom_data *data)
+{
+	char *opt;
+	u8 spi;
+
+	if (!data)
+		data = &eeprom_data;
+
+	if (data->api_rev < PHYTEC_API_REV2)
+		return PHYTEC_EEPROM_INVAL;
+
+	opt = phytec_get_opt(data);
+	if (opt)
+		spi = opt[4] - '0';
+	else
+		spi = PHYTEC_EEPROM_INVAL;
+
+	pr_debug("%s: spi: %u\n", __func__, spi);
+
+	return spi;
+}
+
+/*
+ * Filter ethernet phy information. All i.MX8M boards have this at
+ * the same location.
+ * returns: 0x0 if no ethernet phy is poulated. 0x1 if it is populated.
+ * PHYTEC_EEPROM_INVAL when the data is invalid.
+ */
+u8 phytec_get_imx8m_eth(struct phytec_eeprom_data *data)
+{
+	char *opt;
+	u8 eth;
+
+	if (!data)
+		data = &eeprom_data;
+
+	if (data->api_rev < PHYTEC_API_REV2)
+		return PHYTEC_EEPROM_INVAL;
+
+	opt = phytec_get_opt(data);
+	if (opt) {
+		eth = opt[5] - '0';
+		eth &= 0x1;
+	} else {
+		eth = PHYTEC_EEPROM_INVAL;
+	}
+
+	pr_debug("%s: eth: %u\n", __func__, eth);
+
+	return eth;
+}
+
+/*
+ * Filter RTC information.
+ * returns: 0 if no RTC is poulated. 1 if it is populated.
+ * PHYTEC_EEPROM_INVAL when the data is invalid.
+ */
+u8 phytec_get_imx8mp_rtc(struct phytec_eeprom_data *data)
+{
+	char *opt;
+	u8 rtc;
+
+	if (!data)
+		data = &eeprom_data;
+
+	if (data->api_rev < PHYTEC_API_REV2)
+		return PHYTEC_EEPROM_INVAL;
+
+	opt = phytec_get_opt(data);
+	if (opt) {
+		rtc = opt[5] - '0';
+		rtc &= 0x4;
+		rtc = !(rtc >> 2);
+	} else {
+		rtc = PHYTEC_EEPROM_INVAL;
+	}
+
+	pr_debug("%s: rtc: %u\n", __func__, rtc);
+
+	return rtc;
+}
diff --git a/include/phytec-som-detection.h b/include/phytec-som-detection.h
new file mode 100644
index 000000000000..65c7cb561e1d
--- /dev/null
+++ b/include/phytec-som-detection.h
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2020 PHYTEC Messtechnik GmbH
+ * Author: Teresa Remmet <t.remmet@phytec.de>
+ */
+
+#ifndef _PHYTEC_SOM_DETECTION_H
+#define _PHYTEC_SOM_DETECTION_H
+
+#include <common.h>
+#include <pbl/i2c.h>
+
+#define PHYTEC_MAX_OPTIONS	17
+#define PHYTEC_IMX8MQ_SOM	66
+#define PHYTEC_IMX8MM_SOM	69
+#define PHYTEC_IMX8MP_SOM	70
+
+#define PHYTEC_EEPROM_INVAL	0xff
+
+enum {
+	PHYTEC_API_REV0 = 0,
+	PHYTEC_API_REV1,
+	PHYTEC_API_REV2,
+};
+
+static const char * const phytec_som_type_str[] = {
+	"PCM",
+	"PCL",
+	"KSM",
+	"KSP",
+};
+
+struct phytec_api0_data {
+	u8 pcb_rev;		/* PCB revision of SoM */
+	u8 som_type;		/* SoM type */
+	u8 ksp_no;		/* KSP no */
+	char opt[16];		/* SoM options */
+	u8 mac[6];		/* MAC address (optional) */
+	u8 pad[5];		/* padding */
+	u8 cksum;		/* checksum */
+} __attribute__ ((__packed__));
+
+struct phytec_api2_data {
+	u8 pcb_rev;		/* PCB revision of SoM */
+	u8 pcb_sub_opt_rev;	/* PCB subrevision and opt revision */
+	u8 som_type;		/* SoM type */
+	u8 som_no;		/* SoM number */
+	u8 ksp_no;		/* KSP information */
+	char opt[PHYTEC_MAX_OPTIONS]; /* SoM options */
+	char bom_rev[2];	/* BOM revision */
+	u8 mac[6];		/* MAC address (optional) */
+	u8 crc8;		/* checksum */
+} __attribute__ ((__packed__));
+
+struct phytec_eeprom_data {
+	u8 api_rev;
+	union {
+		struct phytec_api0_data data_api0;
+		struct phytec_api2_data data_api2;
+	} data;
+} __attribute__ ((__packed__));
+
+char *phytec_get_opt(struct phytec_eeprom_data *data);
+int phytec_eeprom_data_setup(struct pbl_i2c *i2c, struct phytec_eeprom_data *data,
+			     int addr, int addr_fallback, u8 cpu_type);
+
+void phytec_print_som_info(struct phytec_eeprom_data *data);
+
+#endif /* _PHYTEC_SOM_DETECTION_H */
diff --git a/include/phytec-som-imx8m-detection.h b/include/phytec-som-imx8m-detection.h
new file mode 100644
index 000000000000..108d40bb4030
--- /dev/null
+++ b/include/phytec-som-imx8m-detection.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2020 PHYTEC Messtechnik GmbH
+ * Author: Teresa Remmet <t.remmet@phytec.de>
+ */
+
+#ifndef _PHYTEC_SOM_IMX8M_DETECTION_H
+#define _PHYTEC_SOM_IMX8M_DETECTION_H
+
+#include <common.h>
+#include <phytec-som-detection.h>
+
+u8 phytec_imx8m_detect(u8 som, char *opt, u8 cpu_type);
+u8 phytec_get_imx8m_ddr_size(struct phytec_eeprom_data *data);
+u8 phytec_get_imx8mp_rtc(struct phytec_eeprom_data *data);
+u8 phytec_get_imx8m_spi(struct phytec_eeprom_data *data);
+u8 phytec_get_imx8m_eth(struct phytec_eeprom_data *data);
+
+#endif /* _PHYTEC_SOM_IMX8M_DETECTION_H */

-- 
2.39.2