pld: add support for gowin devices

Change-Id: Idd1a09514bbbbe0a7b54d69010f6c2f91215fd1d
Signed-off-by: Daniel Anselmi <danselmi@gmx.ch>
Reviewed-on: https://review.openocd.org/c/openocd/+/7368
Tested-by: jenkins
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>

6 files changed, 639 insertions, 0 deletions

diff --git a/doc/openocd.texi b/doc/openocd.texi
index 8099455..cea02bd 100644
--- a/doc/openocd.texi
+++ b/doc/openocd.texi
@@ -8559,6 +8559,13 @@ With a value of -1 for @var{pos} the check will be omitted.
 @end deffn
 
 
+@deffn {FPGA Driver} {gowin}
+This driver can be used to load the bitstream into FPGAs from Gowin.
+It is possible to program the SRAM. Programming the flash is not supported.
+The files @verb{|.fs|} and @verb{|.bin|} generated by Gowin FPGA Designer are supported.
+@end deffn
+
+
 @node General Commands
 @chapter General Commands
 @cindex commands
diff --git a/src/pld/Makefile.am b/src/pld/Makefile.am
index a13f738..22ae9fd 100644
--- a/src/pld/Makefile.am
+++ b/src/pld/Makefile.am
@@ -6,6 +6,7 @@ noinst_LTLIBRARIES += %D%/libpld.la
 	%D%/ecp2_3.c \
 	%D%/ecp5.c \
 	%D%/efinix.c \
+	%D%/gowin.c \
 	%D%/intel.c \
 	%D%/lattice.c \
 	%D%/lattice_bit.c \
diff --git a/src/pld/gowin.c b/src/pld/gowin.c
new file mode 100644
index 0000000..467b799
--- /dev/null
+++ b/src/pld/gowin.c
@@ -0,0 +1,581 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+/***************************************************************************
+ *   Copyright (C) 2022 by Daniel Anselmi                                  *
+ *   danselmi@gmx.ch                                                       *
+ ***************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <jtag/jtag.h>
+#include <jtag/adapter.h>
+#include <helper/bits.h>
+#include "pld.h"
+#include "raw_bit.h"
+
+#define NO_OP                       0x02
+#define ERASE_SRAM                  0x05
+#define SRAM_ERASE_DONE             0x09
+#define IDCODE                      0x11
+#define ADDRESS_INITIALIZATION      0x12
+#define READ_USERCODE               0x13
+#define CONFIG_ENABLE               0x15
+#define TRANSFER_CONFIGURATION_DATA 0x17
+#define CONFIG_DISABLE              0x3A
+#define RELOAD                      0x3C
+#define STATUS_REGISTER             0x41
+#define ERASE_FLASH                 0x75
+#define ENABLE_2ND_FLASH            0x78
+
+#define STAUS_MASK_MEMORY_ERASE     BIT(5)
+#define STAUS_MASK_SYSTEM_EDIT_MODE BIT(7)
+
+struct gowin_pld_device {
+	struct jtag_tap *tap;
+};
+
+struct gowin_bit_file {
+	struct raw_bit_file raw_file;
+	size_t capacity;
+	uint32_t id;
+	uint16_t stored_checksum;
+	int compressed;
+	int crc_en;
+	uint16_t checksum;
+	uint8_t replace8x;
+	uint8_t replace4x;
+	uint8_t replace2x;
+};
+
+static uint64_t gowin_read_fs_file_bitsequence(const char *bits, int length)
+{
+	uint64_t res = 0;
+	for (int i = 0; i < length; i++)
+		res = (res << 1) | (*bits++ == '1' ? 1 : 0);
+	return res;
+}
+
+static int gowin_add_byte_to_bit_file(struct gowin_bit_file *bit_file, uint8_t byte)
+{
+	if (bit_file->raw_file.length + 1 > bit_file->capacity) {
+		uint8_t *buffer;
+		if (bit_file->raw_file.data)
+			buffer = realloc(bit_file->raw_file.data, bit_file->capacity + 8192);
+		else
+			buffer = malloc(8192);
+		if (!buffer) {
+			LOG_ERROR("Out of memory");
+			return ERROR_FAIL;
+		}
+		bit_file->raw_file.data = buffer;
+		bit_file->capacity += 8192;
+	}
+
+	bit_file->raw_file.data[bit_file->raw_file.length++] = byte;
+
+	return ERROR_OK;
+}
+
+static int gowin_read_fs_file_header(struct gowin_bit_file *bit_file, FILE *stream)
+{
+	if (!bit_file)
+		return ERROR_FAIL;
+
+	int end_of_header = 0;
+	while (!end_of_header) {
+		char buffer[256];
+		char *line = fgets(buffer, 256, stream);
+		if (!line || feof(stream) || ferror(stream))
+			return ERROR_FAIL;
+
+		if (line[0] == '/')
+			continue;
+
+		size_t line_length = strlen(line);
+		if (line[line_length - 1] != '\n')
+			return ERROR_FAIL;
+		line_length--;
+
+		for (unsigned int i = 0; i < line_length; i += 8) {
+			uint8_t byte = gowin_read_fs_file_bitsequence(line + i, 8);
+			int retval = gowin_add_byte_to_bit_file(bit_file, byte);
+			if (retval != ERROR_OK)
+				return retval;
+		}
+
+		uint8_t key = gowin_read_fs_file_bitsequence(line, 8);
+		line += 8;
+		uint64_t value = gowin_read_fs_file_bitsequence(line, line_length - 8);
+
+		if (key == 0x06) {
+			bit_file->id = value & 0xffffffff;
+		} else if (key == 0x3B) {
+			end_of_header = 1;
+			bit_file->crc_en = (value & BIT(23)) ? 1 : 0;
+		}
+	}
+
+	return ERROR_OK;
+}
+
+static int gowin_read_fs_file(struct gowin_bit_file *bit_file, const char *filename)
+{
+	FILE *input_file = fopen(filename, "r");
+
+	if (!input_file) {
+		LOG_ERROR("Couldn't open %s: %s", filename, strerror(errno));
+		return ERROR_PLD_FILE_LOAD_FAILED;
+	}
+
+	int retval = gowin_read_fs_file_header(bit_file, input_file);
+	if (retval != ERROR_OK) {
+		free(bit_file->raw_file.data);
+		fclose(input_file);
+		return retval;
+	}
+
+	char digits_buffer[9]; /* 8 + 1 trailing zero */
+	do {
+		char *digits = fgets(digits_buffer, 9, input_file);
+		if (feof(input_file))
+			break;
+		if (!digits || ferror(input_file)) {
+			free(bit_file->raw_file.data);
+			fclose(input_file);
+			return ERROR_FAIL;
+		}
+		if (digits[0] == '\n')
+			continue;
+
+		if (strlen(digits) != 8) {
+			free(bit_file->raw_file.data);
+			fclose(input_file);
+			return ERROR_FAIL;
+		}
+		uint8_t byte = gowin_read_fs_file_bitsequence(digits, 8);
+		retval = gowin_add_byte_to_bit_file(bit_file, byte);
+		if (retval != ERROR_OK) {
+			free(bit_file->raw_file.data);
+			fclose(input_file);
+			return ERROR_FAIL;
+		}
+	} while (1);
+
+	fclose(input_file);
+	return ERROR_OK;
+}
+
+static int gowin_read_file(struct gowin_bit_file *bit_file, const char *filename, bool *is_fs)
+{
+	memset(bit_file, 0, sizeof(struct gowin_bit_file));
+
+	if (!filename || !bit_file)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	const char *file_suffix_pos = strrchr(filename, '.');
+	if (!file_suffix_pos) {
+		LOG_ERROR("Unable to detect filename suffix");
+		return ERROR_PLD_FILE_LOAD_FAILED;
+	}
+
+	/* check if binary .bin or ascii .fs */
+	if (strcasecmp(file_suffix_pos, ".bin") == 0) {
+		*is_fs = false;
+		return cpld_read_raw_bit_file(&bit_file->raw_file, filename);
+	} else if (strcasecmp(file_suffix_pos, ".fs") == 0) {
+		*is_fs = true;
+		return gowin_read_fs_file(bit_file, filename);
+	}
+
+	LOG_ERROR("Filetype not supported, expecting .fs or .bin file");
+	return ERROR_PLD_FILE_LOAD_FAILED;
+}
+
+static int gowin_set_instr(struct jtag_tap *tap, uint8_t new_instr)
+{
+	struct scan_field field;
+	field.num_bits = tap->ir_length;
+	void *t = calloc(DIV_ROUND_UP(field.num_bits, 8), 1);
+	if (!t) {
+		LOG_ERROR("Out of memory");
+		return ERROR_FAIL;
+	}
+	field.out_value = t;
+	buf_set_u32(t, 0, field.num_bits, new_instr);
+	field.in_value = NULL;
+	jtag_add_ir_scan(tap, &field, TAP_IDLE);
+	jtag_add_runtest(3, TAP_IDLE);
+	free(t);
+	return ERROR_OK;
+}
+
+static int gowin_read_register(struct jtag_tap *tap, uint32_t reg, uint32_t *result)
+{
+	struct scan_field field;
+
+	int retval = gowin_set_instr(tap, reg);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = jtag_execute_queue();
+	if (retval != ERROR_OK)
+		return retval;
+
+	uint8_t buf[4] = {0};
+	field.check_mask = NULL;
+	field.check_value = NULL;
+	field.num_bits = 32;
+	field.out_value = buf;
+	field.in_value = buf;
+
+	jtag_add_dr_scan(tap, 1, &field, TAP_IDLE);
+	retval = jtag_execute_queue();
+	*result = le_to_h_u32(buf);
+	return retval;
+}
+
+static int gowin_check_status_flag(struct jtag_tap *tap, uint32_t mask, uint32_t flag)
+{
+	uint32_t status = 0;
+
+	int retries = 0;
+	do {
+		int retval = gowin_read_register(tap, STATUS_REGISTER, &status);
+		if (retval != ERROR_OK)
+			return retval;
+		if (retries++ == 100000)
+			return ERROR_FAIL;
+	} while ((status & mask) != flag);
+
+	return ERROR_OK;
+}
+
+static int gowin_enable_config(struct jtag_tap *tap)
+{
+	int retval = gowin_set_instr(tap, CONFIG_ENABLE);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = jtag_execute_queue();
+	if (retval != ERROR_OK)
+		return retval;
+
+	return gowin_check_status_flag(tap, STAUS_MASK_SYSTEM_EDIT_MODE, STAUS_MASK_SYSTEM_EDIT_MODE);
+}
+
+static int gowin_disable_config(struct jtag_tap *tap)
+{
+	int retval = gowin_set_instr(tap, CONFIG_DISABLE);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = jtag_execute_queue();
+	if (retval != ERROR_OK)
+		return retval;
+
+	return gowin_check_status_flag(tap, STAUS_MASK_SYSTEM_EDIT_MODE, 0);
+}
+
+static int gowin_reload(struct jtag_tap *tap)
+{
+	int retval = gowin_set_instr(tap, RELOAD);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = gowin_set_instr(tap, NO_OP);
+	if (retval != ERROR_OK)
+		return retval;
+	return jtag_execute_queue();
+}
+
+static int gowin_runtest_idle(struct jtag_tap *tap, unsigned int frac_sec)
+{
+	int speed = adapter_get_speed_khz() * 1000;
+	int cycles = DIV_ROUND_UP(speed, frac_sec);
+	jtag_add_runtest(cycles, TAP_IDLE);
+	return jtag_execute_queue();
+}
+
+static int gowin_erase_sram(struct jtag_tap *tap, bool tx_erase_done)
+{
+	/* config is already enabled */
+	int retval = gowin_set_instr(tap, ERASE_SRAM);
+	if (retval != ERROR_OK)
+		return retval;
+	retval = gowin_set_instr(tap, NO_OP);
+	if (retval != ERROR_OK)
+		return retval;
+
+	/* Delay or Run Test 2~10ms */
+	/* 10 ms is worst case for GW2A-55 */
+	jtag_add_sleep(10000);
+	retval = jtag_execute_queue();
+	if (retval != ERROR_OK)
+		return retval;
+
+	retval = gowin_check_status_flag(tap, STAUS_MASK_MEMORY_ERASE,
+									STAUS_MASK_MEMORY_ERASE);
+	if (retval != ERROR_OK)
+		return retval;
+
+	if (tx_erase_done) {
+		retval = gowin_set_instr(tap, SRAM_ERASE_DONE);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = gowin_set_instr(tap, NO_OP);
+		if (retval != ERROR_OK)
+			return retval;
+		retval = jtag_execute_queue();
+		if (retval != ERROR_OK)
+			return retval;
+		/* gen clock cycles in RUN/IDLE for 500us -> 1/500us = 2000/s */
+		retval = gowin_runtest_idle(tap, 2000);
+		if (retval != ERROR_OK)
+			return retval;
+	}
+
+	retval = gowin_set_instr(tap, NO_OP);
+	if (retval != ERROR_OK)
+		return retval;
+	return jtag_execute_queue();
+}
+
+static int gowin_load_to_sram(struct pld_device *pld_device, const char *filename)
+{
+	if (!pld_device)
+		return ERROR_FAIL;
+
+	struct gowin_pld_device *gowin_info = pld_device->driver_priv;
+
+	if (!gowin_info || !gowin_info->tap)
+		return ERROR_FAIL;
+	struct jtag_tap *tap = gowin_info->tap;
+
+	bool is_fs = false;
+	struct gowin_bit_file bit_file;
+	int retval = gowin_read_file(&bit_file, filename, &is_fs);
+	if (retval != ERROR_OK)
+		return retval;
+
+	for (unsigned int i = 0; i < bit_file.raw_file.length; i++)
+		bit_file.raw_file.data[i] = flip_u32(bit_file.raw_file.data[i], 8);
+
+	uint32_t id;
+	retval = gowin_read_register(tap, IDCODE, &id);
+	if (retval != ERROR_OK) {
+		free(bit_file.raw_file.data);
+		return retval;
+	}
+
+	if (is_fs && id != bit_file.id) {
+		free(bit_file.raw_file.data);
+		LOG_ERROR("Id on device (0x%8.8" PRIx32 ") and id in bit-stream (0x%8.8" PRIx32 ") don't match.",
+			id, bit_file.id);
+		return ERROR_FAIL;
+	}
+
+	retval = gowin_enable_config(tap);
+	if (retval != ERROR_OK) {
+		free(bit_file.raw_file.data);
+		return retval;
+	}
+
+	retval = gowin_erase_sram(tap, false);
+	if (retval != ERROR_OK) {
+		free(bit_file.raw_file.data);
+		return retval;
+	}
+
+	retval = gowin_set_instr(tap, ADDRESS_INITIALIZATION);
+	if (retval != ERROR_OK) {
+		free(bit_file.raw_file.data);
+		return retval;
+	}
+	retval = gowin_set_instr(tap, TRANSFER_CONFIGURATION_DATA);
+	if (retval != ERROR_OK) {
+		free(bit_file.raw_file.data);
+		return retval;
+	}
+
+	/* scan out the bitstream */
+	struct scan_field field;
+	field.num_bits = bit_file.raw_file.length * 8;
+	field.out_value = bit_file.raw_file.data;
+	field.in_value = bit_file.raw_file.data;
+	jtag_add_dr_scan(gowin_info->tap, 1, &field, TAP_IDLE);
+	jtag_add_runtest(3, TAP_IDLE);
+
+	retval = jtag_execute_queue();
+	if (retval != ERROR_OK) {
+		free(bit_file.raw_file.data);
+		return retval;
+	}
+
+	retval = gowin_disable_config(tap);
+	free(bit_file.raw_file.data);
+	if (retval != ERROR_OK)
+		return retval;
+
+	retval = gowin_set_instr(gowin_info->tap, NO_OP);
+	if (retval != ERROR_OK)
+		return retval;
+
+	retval = jtag_execute_queue();
+
+	return retval;
+}
+
+static int gowin_read_register_command(struct pld_device *pld_device, uint32_t cmd, uint32_t *value)
+{
+	if (!pld_device)
+		return ERROR_FAIL;
+
+	struct gowin_pld_device *gowin_info = pld_device->driver_priv;
+
+	if (!gowin_info || !gowin_info->tap)
+		return ERROR_FAIL;
+
+	return gowin_read_register(gowin_info->tap, cmd, value);
+}
+
+static int gowin_reload_command(struct pld_device *pld_device)
+{
+	if (!pld_device)
+		return ERROR_FAIL;
+
+	struct gowin_pld_device *gowin_info = pld_device->driver_priv;
+
+	if (!gowin_info || !gowin_info->tap)
+		return ERROR_FAIL;
+
+	return gowin_reload(gowin_info->tap);
+}
+
+COMMAND_HANDLER(gowin_read_status_command_handler)
+{
+	int dev_id;
+
+	if (CMD_ARGC != 1)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], dev_id);
+	struct pld_device *device = get_pld_device_by_num(dev_id);
+	if (!device) {
+		command_print(CMD, "pld device '#%s' is out of bounds", CMD_ARGV[0]);
+		return ERROR_FAIL;
+	}
+
+	uint32_t status = 0;
+	int retval = gowin_read_register_command(device, STATUS_REGISTER, &status);
+
+	if (retval == ERROR_OK)
+		command_print(CMD, "0x%8.8" PRIx32, status);
+
+	return retval;
+}
+
+COMMAND_HANDLER(gowin_read_user_register_command_handler)
+{
+	int dev_id;
+
+	if (CMD_ARGC != 1)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], dev_id);
+	struct pld_device *device = get_pld_device_by_num(dev_id);
+	if (!device) {
+		command_print(CMD, "pld device '#%s' is out of bounds", CMD_ARGV[0]);
+		return ERROR_FAIL;
+	}
+
+	uint32_t user_reg = 0;
+	int retval = gowin_read_register_command(device, READ_USERCODE, &user_reg);
+
+	if (retval == ERROR_OK)
+		command_print(CMD, "0x%8.8" PRIx32, user_reg);
+
+	return retval;
+}
+
+COMMAND_HANDLER(gowin_reload_command_handler)
+{
+	int dev_id;
+
+	if (CMD_ARGC != 1)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], dev_id);
+	struct pld_device *device = get_pld_device_by_num(dev_id);
+	if (!device) {
+		command_print(CMD, "pld device '#%s' is out of bounds", CMD_ARGV[0]);
+		return ERROR_FAIL;
+	}
+
+	return gowin_reload_command(device);
+}
+
+static const struct command_registration gowin_exec_command_handlers[] = {
+	{
+		.name = "read_status",
+		.mode = COMMAND_EXEC,
+		.handler = gowin_read_status_command_handler,
+		.help = "reading status register from FPGA",
+		.usage = "num_pld",
+	}, {
+		.name = "read_user",
+		.mode = COMMAND_EXEC,
+		.handler = gowin_read_user_register_command_handler,
+		.help = "reading user register from FPGA",
+		.usage = "num_pld",
+	}, {
+		.name = "reload",
+		.mode = COMMAND_EXEC,
+		.handler = gowin_reload_command_handler,
+		.help = "reloading bitstream from flash to SRAM",
+		.usage = "num_pld",
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+static const struct command_registration gowin_command_handler[] = {
+	{
+		.name = "gowin",
+		.mode = COMMAND_ANY,
+		.help = "gowin specific commands",
+		.usage = "",
+		.chain = gowin_exec_command_handlers
+	},
+	COMMAND_REGISTRATION_DONE
+};
+
+PLD_DEVICE_COMMAND_HANDLER(gowin_pld_device_command)
+{
+	struct jtag_tap *tap;
+
+	struct gowin_pld_device *gowin_info;
+
+	if (CMD_ARGC != 2)
+		return ERROR_COMMAND_SYNTAX_ERROR;
+
+	tap = jtag_tap_by_string(CMD_ARGV[1]);
+	if (!tap) {
+		command_print(CMD, "Tap: %s does not exist", CMD_ARGV[1]);
+		return ERROR_FAIL;
+	}
+
+	gowin_info = malloc(sizeof(struct gowin_pld_device));
+	if (!gowin_info) {
+		LOG_ERROR("Out of memory");
+		return ERROR_FAIL;
+	}
+	gowin_info->tap = tap;
+
+	pld->driver_priv = gowin_info;
+
+	return ERROR_OK;
+}
+
+struct pld_driver gowin_pld = {
+	.name = "gowin",
+	.commands = gowin_command_handler,
+	.pld_device_command = &gowin_pld_device_command,
+	.load = &gowin_load_to_sram,
+};
diff --git a/src/pld/pld.c b/src/pld/pld.c
index f4f79ba..d9e01f1 100644
--- a/src/pld/pld.c
+++ b/src/pld/pld.c
@@ -19,12 +19,14 @@
 /* pld drivers
  */
 extern struct pld_driver efinix_pld;
+extern struct pld_driver gowin_pld;
 extern struct pld_driver intel_pld;
 extern struct pld_driver lattice_pld;
 extern struct pld_driver virtex2_pld;
 
 static struct pld_driver *pld_drivers[] = {
 	&efinix_pld,
+	&gowin_pld,
 	&intel_pld,
 	&lattice_pld,
 	&virtex2_pld,
diff --git a/tcl/board/gowin_runber.cfg b/tcl/board/gowin_runber.cfg
new file mode 100644
index 0000000..9496c6f
--- /dev/null
+++ b/tcl/board/gowin_runber.cfg
@@ -0,0 +1,19 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+# Gowin RUNBER FPGA Development Board
+# https://www.seeedstudio.com/Gowin-RUNBER-Development-Board-p-4779.html
+
+adapter driver ftdi
+ftdi vid_pid 0x0403 0x6010
+
+ftdi channel 0
+ftdi layout_init 0x0008 0x008b
+reset_config none
+transport select jtag
+adapter speed 6000
+
+source [find fpga/gowin_gw1n.cfg]
+
+
+#openocd -f board/gowin_runber.cfg  -c "init" -c "pld load 0 impl/pnr/gw1n_blinker.fs"
+#ipdbg -start -tap gw1n.tap -hub 0x42 -port 5555 -tool 0
diff --git a/tcl/fpga/gowin_gw1n.cfg b/tcl/fpga/gowin_gw1n.cfg
new file mode 100644
index 0000000..43d66b7
--- /dev/null
+++ b/tcl/fpga/gowin_gw1n.cfg
@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+#  Gowin FPGA IDCODEs
+# from JTAG Programming and Configuration Guide
+# http://cdn.gowinsemi.com.cn/TN653E.pdf
+
+if { [info exists CHIPNAME] } {
+	set _CHIPNAME $CHIPNAME
+} else {
+	set _CHIPNAME gw1n
+}
+
+jtag newtap $_CHIPNAME tap -irlen 8 -ignore-version \
+	-expected-id 0x0900281B \
+	-expected-id 0x0900381B \
+	-expected-id 0x0100681B \
+	-expected-id 0x0300081B \
+	-expected-id 0x0300181B \
+	-expected-id 0x0120681B \
+	-expected-id 0x0100381B \
+	-expected-id 0x1100381B \
+	-expected-id 0x0100981B \
+	-expected-id 0x1100581B \
+	-expected-id 0x1100481B \
+	-expected-id 0x0100181B \
+	-expected-id 0x1100181B \
+	-expected-id 0x0100481B
+
+pld device gowin $_CHIPNAME.tap