X-Git-Url: https://review.openocd.org/gitweb?p=openocd.git;a=blobdiff_plain;f=src%2Fjtag%2Fpresto.c;h=f22bd9eb862e487794aa26cb6a1b11973b24b2e2;hp=01cf08a1a902b4096469e7862a9b396566a2a4d0;hb=833e7f5248778bcb31b4db1a1b91160995415203;hpb=e378eeec3634e921405acb0cb86bde4cf53a76d7

diff --git a/src/jtag/presto.c b/src/jtag/presto.c
index 01cf08a1a9..f22bd9eb86 100644
--- a/src/jtag/presto.c
+++ b/src/jtag/presto.c
@@ -23,26 +23,12 @@
 
 #if IS_CYGWIN == 1
 #include "windows.h"
-#undef ERROR
 #endif
 
-#include "replacements.h"
-
-/* project specific includes */
-#include "log.h"
-#include "types.h"
-#include "jtag.h"
-#include "configuration.h"
+#include "interface.h"
 #include "time_support.h"
 #include "bitq.h"
 
-/* system includes */
-#include <string.h>
-#include <stdlib.h>
-#include <unistd.h>
-
-#include <sys/time.h>
-#include <time.h>
 
 /* PRESTO access library includes */
 #if BUILD_PRESTO_FTD2XX == 1
@@ -53,44 +39,8 @@
 #error "BUG: either FTD2XX and LIBFTDI has to be used"
 #endif
 
-
-int presto_jtag_speed(int speed);
-int presto_jtag_register_commands(struct command_context_s *cmd_ctx);
-int presto_jtag_init(void);
-int presto_jtag_quit(void);
-
-jtag_interface_t presto_interface =
-{
-	.name = "presto",
-	.execute_queue = bitq_execute_queue,
-	.speed = presto_jtag_speed,
-	.register_commands = presto_jtag_register_commands,
-	.init = presto_jtag_init,
-	.quit = presto_jtag_quit,
-};
-
-
-int presto_bitq_out(int tms, int tdi, int tdo_req);
-int presto_bitq_flush(void);
-int presto_bitq_sleep(unsigned long us);
-int presto_bitq_reset(int trst, int srst);
-int presto_bitq_in_rdy(void);
-int presto_bitq_in(void);
-
-bitq_interface_t presto_bitq =
-{
-	.out = presto_bitq_out,
-	.flush = presto_bitq_flush,
-	.sleep = presto_bitq_sleep,
-	.reset = presto_bitq_reset,
-	.in_rdy = presto_bitq_in_rdy,
-	.in = presto_bitq_in,
-};
-
-
 /* -------------------------------------------------------------------------- */
 
-
 #define FT_DEVICE_NAME_LEN 64
 #define FT_DEVICE_SERNUM_LEN 64
 
@@ -100,8 +50,7 @@ bitq_interface_t presto_bitq =
 
 #define BUFFER_SIZE (64*62)
 
-typedef struct presto_s
-{
+struct presto {
 #if BUILD_PRESTO_FTD2XX == 1
 	FT_HANDLE handle;
 	FT_STATUS status;
@@ -112,10 +61,10 @@ typedef struct presto_s
 
 	char serial[FT_DEVICE_SERNUM_LEN];
 
-	u8 buff_out[BUFFER_SIZE];
+	uint8_t buff_out[BUFFER_SIZE];
 	int buff_out_pos;
 
-	u8 buff_in[BUFFER_SIZE];
+	uint8_t buff_in[BUFFER_SIZE];
 	int buff_in_exp; /* expected in buffer length */
 	int buff_in_len; /* length of data received */
 	int buff_in_pos;
@@ -125,35 +74,37 @@ typedef struct presto_s
 
 	int jtag_tms; /* last tms state */
 	int jtag_tck; /* last tck state */
+	int jtag_rst; /* last trst state */
 
 	int jtag_tdi_data;
 	int jtag_tdi_count;
 
-} presto_t;
+	int jtag_speed;
+};
 
-presto_t presto_state;
-presto_t *presto = &presto_state;
+static struct presto presto_state;
+static struct presto *presto = &presto_state;
 
-u8 presto_init_seq[] =
+static uint8_t presto_init_seq[] =
 {
 	0x80, 0xA0, 0xA8, 0xB0, 0xC0, 0xE0
 };
 
-int presto_write(u8 *buf, int size)
+static int presto_write(uint8_t *buf, uint32_t size)
 {
 #if BUILD_PRESTO_FTD2XX == 1
 	DWORD ftbytes;
 	if ((presto->status = FT_Write(presto->handle, buf, size, &ftbytes)) != FT_OK)
 	{
-		ERROR("FT_Write returned: %lu", presto->status);
+		LOG_ERROR("FT_Write returned: %lu", presto->status);
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
 #elif BUILD_PRESTO_LIBFTDI == 1
-	u32 ftbytes;
+	uint32_t ftbytes;
 	if ((presto->retval = ftdi_write_data(&presto->ftdic, buf, size)) < 0)
 	{
-		ERROR("ftdi_write_data: %s", ftdi_get_error_string(&presto->ftdic));
+		LOG_ERROR("ftdi_write_data: %s", ftdi_get_error_string(&presto->ftdic));
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 	ftbytes = presto->retval;
@@ -161,25 +112,26 @@ int presto_write(u8 *buf, int size)
 
 	if (ftbytes != size)
 	{
-		ERROR("couldn't write the requested number of bytes to PRESTO (%i < %i)", ftbytes, size);
+		LOG_ERROR("couldn't write the requested number of bytes to PRESTO (%u < %u)",
+			  (unsigned)ftbytes, (unsigned)size);
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
 	return ERROR_OK;
 }
 
-int presto_read(u8* buf, int size)
+static int presto_read(uint8_t* buf, uint32_t size)
 {
 #if BUILD_PRESTO_FTD2XX == 1
 	DWORD ftbytes;
 	if ((presto->status = FT_Read(presto->handle, buf, size, &ftbytes)) != FT_OK)
 	{
-		ERROR("FT_Read returned: %lu", presto->status);
+		LOG_ERROR("FT_Read returned: %lu", presto->status);
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
 #elif BUILD_PRESTO_LIBFTDI == 1
-	u32 ftbytes = 0;
+	uint32_t ftbytes = 0;
 
 	struct timeval timeout, now;
 	gettimeofday(&timeout, NULL);
@@ -189,7 +141,7 @@ int presto_read(u8* buf, int size)
 	{
 		if ((presto->retval = ftdi_read_data(&presto->ftdic, buf + ftbytes, size - ftbytes)) < 0)
 		{
-			ERROR("ftdi_read_data: %s", ftdi_get_error_string(&presto->ftdic));
+			LOG_ERROR("ftdi_read_data: %s", ftdi_get_error_string(&presto->ftdic));
 			return ERROR_JTAG_DEVICE_ERROR;
 		}
 		ftbytes += presto->retval;
@@ -203,7 +155,8 @@ int presto_read(u8* buf, int size)
 	if (ftbytes != size)
 	{
 		/* this is just a warning, there might have been timeout when detecting PRESTO, which is not fatal */
-		WARNING("couldn't read the requested number of bytes from PRESTO (%i < %i)", ftbytes, size);
+		LOG_WARNING("couldn't read the requested number of bytes from PRESTO (%u < %u)",
+			    (unsigned)ftbytes, (unsigned)size);
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
@@ -211,9 +164,9 @@ int presto_read(u8* buf, int size)
 }
 
 #if BUILD_PRESTO_FTD2XX == 1
-int presto_open_ftd2xx(char *req_serial)
+static int presto_open_ftd2xx(char *req_serial)
 {
-	int i;
+	uint32_t i;
 	DWORD numdevs;
 	DWORD vidpid;
 	char devname[FT_DEVICE_NAME_LEN];
@@ -228,27 +181,27 @@ int presto_open_ftd2xx(char *req_serial)
 	/* Add non-standard Vid/Pid to the linux driver */
 	if ((presto->status = FT_SetVIDPID(PRESTO_VID, PRESTO_PID)) != FT_OK)
 	{
-		ERROR("couldn't add PRESTO VID/PID");
+		LOG_ERROR("couldn't add PRESTO VID/PID");
 		exit(-1);
 	}
 #endif
 
 	if ((presto->status = FT_ListDevices(&numdevs, NULL, FT_LIST_NUMBER_ONLY)) != FT_OK)
 	{
-		ERROR("FT_ListDevices failed: %i", (int)presto->status);
+		LOG_ERROR("FT_ListDevices failed: %i", (int)presto->status);
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
-	DEBUG("FTDI devices available: %i", numdevs);
+	LOG_DEBUG("FTDI devices available: %lu", numdevs);
 	for (i = 0; i < numdevs; i++)
 	{
 		if ((presto->status = FT_Open(i, &(presto->handle))) != FT_OK)
 		{
 			/* this is not fatal, the device may be legitimately open by other process, hence debug message only */
-			DEBUG("FT_Open failed: %i", (int)presto->status);
+			LOG_DEBUG("FT_Open failed: %i", (int)presto->status);
 			continue;
 		}
-		DEBUG("FTDI device %i open", i);
+		LOG_DEBUG("FTDI device %i open", (int)i);
 
 		if ((presto->status = FT_GetDeviceInfo(presto->handle, &device, &vidpid,
 				presto->serial, devname, NULL)) == FT_OK)
@@ -258,9 +211,9 @@ int presto_open_ftd2xx(char *req_serial)
 				break;
 		}
 		else
-			DEBUG("FT_GetDeviceInfo failed: %i", presto->status);
+			LOG_DEBUG("FT_GetDeviceInfo failed: %lu", presto->status);
 
-		DEBUG("FTDI device %i does not match, closing", i);
+		LOG_DEBUG("FTDI device %i does not match, closing", (int)i);
 		FT_Close(presto->handle);
 		presto->handle = (FT_HANDLE)INVALID_HANDLE_VALUE;
 	}
@@ -288,9 +241,9 @@ int presto_open_ftd2xx(char *req_serial)
 	if ((presto->status = FT_Read(presto->handle, &presto_data, 1, &ftbytes)) != FT_OK)
 		return ERROR_JTAG_DEVICE_ERROR;
 
-	if (ftbytes!=1)
+	if (ftbytes != 1)
 	{
-		DEBUG("PRESTO reset");
+		LOG_DEBUG("PRESTO reset");
 
 		if ((presto->status = FT_Purge(presto->handle, FT_PURGE_TX | FT_PURGE_RX)) != FT_OK)
 			return ERROR_JTAG_DEVICE_ERROR;
@@ -301,7 +254,7 @@ int presto_open_ftd2xx(char *req_serial)
 
 		presto_data = 0;
 		for (i = 0; i < 4 * 62; i++)
-			if ((presto->status=FT_Write(presto->handle, &presto_data, 1, &ftbytes)) != FT_OK)
+			if ((presto->status = FT_Write(presto->handle, &presto_data, 1, &ftbytes)) != FT_OK)
 				return ERROR_JTAG_DEVICE_ERROR;
 
 		usleep(100000);
@@ -322,9 +275,9 @@ int presto_open_ftd2xx(char *req_serial)
 		if ((presto->status = FT_Read(presto->handle, &presto_data, 1, &ftbytes)) != FT_OK)
 			return ERROR_JTAG_DEVICE_ERROR;
 
-		if (ftbytes!=1)
+		if (ftbytes != 1)
 		{
-			DEBUG("PRESTO not responding");
+			LOG_DEBUG("PRESTO not responding");
 			return ERROR_JTAG_DEVICE_ERROR;
 		}
 	}
@@ -341,54 +294,54 @@ int presto_open_ftd2xx(char *req_serial)
 }
 
 #elif BUILD_PRESTO_LIBFTDI == 1
-int presto_open_libftdi(char *req_serial)
+static int presto_open_libftdi(char *req_serial)
 {
-	u8 presto_data;
+	uint8_t presto_data;
 
-	DEBUG("searching for PRESTO using libftdi");
+	LOG_DEBUG("searching for PRESTO using libftdi");
 
 	/* initialize FTDI context structure */
 	if (ftdi_init(&presto->ftdic) < 0)
 	{
-		ERROR("unable to init libftdi: %s", presto->ftdic.error_str);
+		LOG_ERROR("unable to init libftdi: %s", presto->ftdic.error_str);
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
 	/* context, vendor id, product id */
 	if (ftdi_usb_open_desc(&presto->ftdic, PRESTO_VID, PRESTO_PID, NULL, req_serial) < 0)
 	{
-		ERROR("unable to open PRESTO: %s", presto->ftdic.error_str);
+		LOG_ERROR("unable to open PRESTO: %s", presto->ftdic.error_str);
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
 	if (ftdi_usb_reset(&presto->ftdic) < 0)
 	{
-		ERROR("unable to reset PRESTO device");
+		LOG_ERROR("unable to reset PRESTO device");
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
 	if (ftdi_set_latency_timer(&presto->ftdic, 1) < 0)
 	{
-		ERROR("unable to set latency timer");
+		LOG_ERROR("unable to set latency timer");
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
 	if (ftdi_usb_purge_buffers(&presto->ftdic) < 0)
 	{
-		ERROR("unable to purge PRESTO buffers");
+		LOG_ERROR("unable to purge PRESTO buffers");
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
 	presto_data = 0xD0;
 	if (presto_write(&presto_data, 1) != ERROR_OK)
 	{
-		ERROR("error writing to PRESTO");
+		LOG_ERROR("error writing to PRESTO");
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
 	if (presto_read(&presto_data, 1) != ERROR_OK)
 	{
-		DEBUG("no response from PRESTO, retrying");
+		LOG_DEBUG("no response from PRESTO, retrying");
 
 		if (ftdi_usb_purge_buffers(&presto->ftdic) < 0)
 			return ERROR_JTAG_DEVICE_ERROR;
@@ -399,14 +352,14 @@ int presto_open_libftdi(char *req_serial)
 
 		if (presto_read(&presto_data, 1) != ERROR_OK)
 		{
-			ERROR("no response from PRESTO, giving up");
+			LOG_ERROR("no response from PRESTO, giving up");
 			return ERROR_JTAG_DEVICE_ERROR;
 		}
 	}
 
 	if (presto_write(presto_init_seq, sizeof(presto_init_seq)) != ERROR_OK)
 	{
-		ERROR("error writing PRESTO init sequence");
+		LOG_ERROR("error writing PRESTO init sequence");
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
@@ -414,20 +367,23 @@ int presto_open_libftdi(char *req_serial)
 }
 #endif /* BUILD_PRESTO_LIBFTDI == 1 */
 
-int presto_open(char *req_serial)
+static int presto_open(char *req_serial)
 {
-	presto->buff_out_pos=0;
-	presto->buff_in_pos=0;
-	presto->buff_in_len=0;
-	presto->buff_in_exp=0;
+	presto->buff_out_pos = 0;
+	presto->buff_in_pos = 0;
+	presto->buff_in_len = 0;
+	presto->buff_in_exp = 0;
+
+	presto->total_out = 0;
+	presto->total_in = 0;
 
-	presto->total_out=0;
-	presto->total_in=0;
+	presto->jtag_tms = 0;
+	presto->jtag_tck = 0;
+	presto->jtag_rst = 0;
+	presto->jtag_tdi_data = 0;
+	presto->jtag_tdi_count = 0;
 
-	presto->jtag_tms=0;
-	presto->jtag_tck=0;
-	presto->jtag_tdi_data=0;
-	presto->jtag_tdi_count=0;
+	presto->jtag_speed = 0;
 
 #if BUILD_PRESTO_FTD2XX == 1
 	return presto_open_ftd2xx(req_serial);
@@ -436,7 +392,7 @@ int presto_open(char *req_serial)
 #endif
 }
 
-int presto_close(void)
+static int presto_close(void)
 {
 
 	int result = ERROR_OK;
@@ -480,8 +436,7 @@ int presto_close(void)
 	return result;
 }
 
-
-int presto_flush(void)
+static int presto_flush(void)
 {
 	if (presto->buff_out_pos == 0)
 		return ERROR_OK;
@@ -492,7 +447,7 @@ int presto_flush(void)
 	if (presto->retval < 0)
 #endif
 	{
-		DEBUG("error in previous communication, canceling I/O operation");
+		LOG_DEBUG("error in previous communication, canceling I/O operation");
 		return ERROR_JTAG_DEVICE_ERROR;
 	}
 
@@ -524,14 +479,13 @@ int presto_flush(void)
 	return ERROR_OK;
 }
 
-
-int presto_sendbyte(int data)
+static int presto_sendbyte(int data)
 {
 	if (data == EOF) return presto_flush();
 
 	if (presto->buff_out_pos < BUFFER_SIZE)
 	{
-		presto->buff_out[presto->buff_out_pos++] = (u8)data;
+		presto->buff_out[presto->buff_out_pos++] = (uint8_t)data;
 		if (((data & 0xC0) == 0x40) || ((data & 0xD0)== 0xD0))
 			presto->buff_in_exp++;
 	}
@@ -542,15 +496,15 @@ int presto_sendbyte(int data)
 	if (presto->buff_out_pos >= BUFFER_SIZE)
 #elif BUILD_PRESTO_LIBFTDI == 1
 	/* libftdi does not do background read, be sure that USB IN buffer does not overflow (128 bytes only!) */
-	if (presto->buff_out_pos >= BUFFER_SIZE || presto->buff_in_exp==128)
+	if (presto->buff_out_pos >= BUFFER_SIZE || presto->buff_in_exp == 128)
 #endif
 		return presto_flush();
 
 	return ERROR_OK;
 }
 
-
-int presto_getbyte(void)
+#if 0
+static int presto_getbyte(void)
 {
 	if (presto->buff_in_pos < presto->buff_in_len)
 		return presto->buff_in[presto->buff_in_pos++];
@@ -561,113 +515,125 @@ int presto_getbyte(void)
 	if (presto_flush() != ERROR_OK)
 		return -1;
 
-	if (presto->buff_in_pos<presto->buff_in_len)
+	if (presto->buff_in_pos < presto->buff_in_len)
 		return presto->buff_in[presto->buff_in_pos++];
 
 	return -1;
 }
-
+#endif
 
 /* -------------------------------------------------------------------------- */
 
-
-int presto_bitq_out(int tms, int tdi, int tdo_req)
+static int presto_tdi_flush(void)
 {
-	unsigned char cmdparam;
+	if (presto->jtag_tdi_count == 0)
+		return 0;
 
 	if (presto->jtag_tck == 0)
 	{
-		presto_sendbyte(0xA4);
-		presto->jtag_tck = 1;
+		LOG_ERROR("BUG: unexpected TAP condition, TCK low");
+		return -1;
 	}
 
-	else if (!tdo_req && tms == presto->jtag_tms)
-	{
-		if (presto->jtag_tdi_count == 0)
-			presto->jtag_tdi_data = (tdi != 0);
-		else
-			presto->jtag_tdi_data |= (tdi != 0) << presto->jtag_tdi_count;
+	presto->jtag_tdi_data |= (presto->jtag_tdi_count - 1) << 4;
+	presto_sendbyte(presto->jtag_tdi_data);
+	presto->jtag_tdi_count = 0;
+	presto->jtag_tdi_data = 0;
 
-		if (++presto->jtag_tdi_count == 4)
-		{
-			presto->jtag_tdi_data |= (presto->jtag_tdi_count - 1) << 4;
-			presto_sendbyte(presto->jtag_tdi_data);
-			presto->jtag_tdi_count = 0;
-		}
-		return 0;
+	return 0;
+}
+
+static int presto_tck_idle(void)
+{
+	if (presto->jtag_tck == 1)
+	{
+		presto_sendbyte(0xCA);
+		presto->jtag_tck = 0;
 	}
 
-	if (presto->jtag_tdi_count)
+	return 0;
+}
+
+/* -------------------------------------------------------------------------- */
+
+static int presto_bitq_out(int tms, int tdi, int tdo_req)
+{
+	int i;
+	unsigned char cmd;
+
+	if (presto->jtag_tck == 0)
 	{
-		presto->jtag_tdi_data |= (presto->jtag_tdi_count - 1) << 4;
-		presto_sendbyte(presto->jtag_tdi_data);
-		presto->jtag_tdi_count = 0;
+		presto_sendbyte(0xA4); /* LED idicator - JTAG active */
 	}
+	else if (presto->jtag_speed == 0 && !tdo_req && tms == presto->jtag_tms)
+	{
+		presto->jtag_tdi_data |= (tdi != 0) << presto->jtag_tdi_count;
 
-	if (tdi)
-		cmdparam = 0x0B;
-	else
-		cmdparam = 0x0A;
+		if (++presto->jtag_tdi_count == 4)
+			presto_tdi_flush();
+
+		return 0;
+	}
 
-	presto_sendbyte( 0xC0 | cmdparam);
+	presto_tdi_flush();
+
+	cmd = tdi ? 0xCB : 0xCA;
+	presto_sendbyte(cmd);
 
 	if (tms != presto->jtag_tms)
 	{
-		if (tms)
-			presto_sendbyte(0xEC);
-		else
-			presto_sendbyte(0xE8);
+		presto_sendbyte((tms ? 0xEC : 0xE8) | (presto->jtag_rst ? 0x02 : 0));
 		presto->jtag_tms = tms;
 	}
 
-	if (tdo_req)
-		presto_sendbyte(0xD4 | cmdparam);
-	else
-		presto_sendbyte(0xC4|cmdparam);
+	/* delay with TCK low */
+	for (i = presto->jtag_speed; i > 1; i--)
+		presto_sendbyte(cmd);
+
+	cmd |= 0x04;
+	presto_sendbyte(cmd | (tdo_req ? 0x10 : 0));
+
+	/* delay with TCK high */
+	for (i = presto->jtag_speed; i > 1; i--)
+		presto_sendbyte(cmd);
+
+	presto->jtag_tck = 1;
 
 	return 0;
 }
 
-
-int presto_bitq_flush(void)
+static int presto_bitq_flush(void)
 {
-	if (presto->jtag_tdi_count)
-	{
-		presto->jtag_tdi_data |= (presto->jtag_tdi_count - 1) << 4;
-		presto_sendbyte(presto->jtag_tdi_data);
-		presto->jtag_tdi_count = 0;
-	}
+	presto_tdi_flush();
+	presto_tck_idle();
 
-	presto_sendbyte(0xCA);
-	presto->jtag_tck = 0;
-
-	presto_sendbyte(0xA0);
+	presto_sendbyte(0xA0); /* LED idicator - JTAG idle */
 
 	return presto_flush();
 }
 
-
-int presto_bitq_in_rdy(void)
+static int presto_bitq_in_rdy(void)
 {
-	if (presto->buff_in_pos>=presto->buff_in_len)
+	if (presto->buff_in_pos >= presto->buff_in_len)
 		return 0;
 	return presto->buff_in_len-presto->buff_in_pos;
 }
 
-
-int presto_bitq_in(void)
+static int presto_bitq_in(void)
 {
-	if (presto->buff_in_pos>=presto->buff_in_len)
+	if (presto->buff_in_pos >= presto->buff_in_len)
 		return -1;
 	if (presto->buff_in[presto->buff_in_pos++]&0x08) return 1;
 	return 0;
 }
 
-
-int presto_bitq_sleep(unsigned long us)
+static int presto_bitq_sleep(unsigned long us)
 {
 	long waits;
 
+	presto_tdi_flush();
+	presto_tck_idle();
+
 	if (us > 100000)
 	{
 		presto_bitq_flush();
@@ -682,101 +648,129 @@ int presto_bitq_sleep(unsigned long us)
 	return 0;
 }
 
-
-int presto_bitq_reset(int trst, int srst)
+static int presto_bitq_reset(int trst, int srst)
 {
-	unsigned char cmd;
+	presto_tdi_flush();
+	presto_tck_idle();
 
-	cmd = 0xE8;
-	if (presto->jtag_tms)
-		cmd |= 0x04;
+	/* add a delay after possible TCK transition */
+	presto_sendbyte(0x80);
+	presto_sendbyte(0x80);
 
-	if (trst || srst)
-		cmd |= 0x02;
+	presto->jtag_rst = trst || srst;
+	presto_sendbyte((presto->jtag_rst ? 0xEA : 0xE8) | (presto->jtag_tms ? 0x04 : 0));
 
-	presto_sendbyte(cmd);
 	return 0;
 }
 
+static struct bitq_interface presto_bitq = {
+		.out = &presto_bitq_out,
+		.flush = &presto_bitq_flush,
+		.sleep = &presto_bitq_sleep,
+		.reset = &presto_bitq_reset,
+		.in_rdy = &presto_bitq_in_rdy,
+		.in = &presto_bitq_in,
+	};
 
 /* -------------------------------------------------------------------------- */
 
-char *presto_speed_text[4] =
+static int presto_jtag_khz(int khz, int *jtag_speed)
 {
-	"3 MHz",
-	"1.5 MHz",
-	"750 kHz",
-	"93.75 kHz"
-};
+	if (khz < 0)
+	{
+		*jtag_speed = 0;
+		return ERROR_INVALID_ARGUMENTS;
+	}
 
-int presto_jtag_speed(int speed)
-{
+	if (khz >= 3000) *jtag_speed = 0;
+	else *jtag_speed = (1000 + khz-1)/khz;
 
-	if ((speed < 0) || (speed > 3))
+	return 0;
+}
+
+static int presto_jtag_speed_div(int speed, int *khz)
+{
+	if ((speed < 0) || (speed > 1000))
 	{
-		INFO("valid speed values: 0 (3 MHz), 1 (1.5 MHz), 2 (750 kHz) and 3 (93.75 kHz)");
+		*khz = 0;
 		return ERROR_INVALID_ARGUMENTS;
 	}
 
-	jtag_speed = speed;
-	INFO("setting speed to %d, max. TCK freq. is %s", speed, presto_speed_text[speed]);
-	return presto_sendbyte(0xA8 | speed);
+	if (speed == 0) *khz = 3000;
+	else *khz = 1000/speed;
+
+	return 0;
 }
 
+static int presto_jtag_speed(int speed)
+{
+	int khz;
+
+	if (presto_jtag_speed_div(speed, &khz))
+	{
+		return ERROR_INVALID_ARGUMENTS;
+	}
 
-char *presto_serial;
+	presto->jtag_speed = speed;
 
-int presto_handle_serial_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+	if (khz%1000 == 0)
+		LOG_INFO("setting speed to %d, max. TCK freq. is %d MHz", speed, khz/1000);
+	else
+		LOG_INFO("setting speed to %d, max. TCK freq. is %d kHz", speed, khz);
+
+	return 0;
+}
+
+static char *presto_serial;
+
+COMMAND_HANDLER(presto_handle_serial_command)
 {
-	if (argc == 1)
+	if (CMD_ARGC == 1)
 	{
 		if (presto_serial)
 			free(presto_serial);
-		presto_serial = strdup(args[0]);
+		presto_serial = strdup(CMD_ARGV[0]);
 	}
 	else
 	{
-		ERROR("expected exactly one argument to presto_serial <serial-number>");
+		LOG_ERROR("expected exactly one argument to presto_serial <serial-number>");
 	}
 
 	return ERROR_OK;
 }
 
-
-int presto_jtag_register_commands(struct command_context_s *cmd_ctx)
+static int presto_jtag_register_commands(struct command_context *cmd_ctx)
 {
-	register_command(cmd_ctx, NULL, "presto_serial", presto_handle_serial_command,
+	COMMAND_REGISTER(cmd_ctx, NULL, "presto_serial", presto_handle_serial_command,
 		COMMAND_CONFIG, NULL);
 	return ERROR_OK;
 }
 
-
-int presto_jtag_init(void)
+static int presto_jtag_init(void)
 {
 	if (presto_open(presto_serial) != ERROR_OK)
 	{
 		presto_close();
 		if (presto_serial != NULL)
-			ERROR("Cannot open PRESTO, serial number '%s'", presto_serial);
+			LOG_ERROR("Cannot open PRESTO, serial number '%s'", presto_serial);
 		else
-			ERROR("Cannot open PRESTO");
+			LOG_ERROR("Cannot open PRESTO");
 		return ERROR_JTAG_INIT_FAILED;
 	}
-	INFO("PRESTO open, serial number '%s'", presto->serial);
+	LOG_INFO("PRESTO open, serial number '%s'", presto->serial);
 
 	/* use JTAG speed setting from configuration file */
-	presto_jtag_speed(jtag_speed);
+	presto_jtag_speed(jtag_get_speed());
 
 	bitq_interface = &presto_bitq;
 	return ERROR_OK;
 }
 
-
-int presto_jtag_quit(void)
+static int presto_jtag_quit(void)
 {
 	bitq_cleanup();
 	presto_close();
-	INFO("PRESTO closed");
+	LOG_INFO("PRESTO closed");
 
 	if (presto_serial)
 	{
@@ -786,3 +780,14 @@ int presto_jtag_quit(void)
 
 	return ERROR_OK;
 }
+
+struct jtag_interface presto_interface = {
+		.name = "presto",
+		.execute_queue = &bitq_execute_queue,
+		.speed = &presto_jtag_speed,
+		.khz = &presto_jtag_khz,
+		.speed_div = &presto_jtag_speed_div,
+		.register_commands = &presto_jtag_register_commands,
+		.init = &presto_jtag_init,
+		.quit = &presto_jtag_quit,
+	};