Signed-off-by: Wjatscheslaw Stoljarski
<wjatscheslaw.stoljar...@kiwigrid.com>
---
drivers/Kconfig | 1 +
drivers/Makefile | 1 +
drivers/misc/Kconfig | 27 ++++
drivers/misc/Makefile | 5 +
drivers/misc/jtag.c | 395
+++++++++++++++++++++++++++++++++++++++++++++++++
include/jtag.h | 113 ++++++++++++++
6 files changed, 542 insertions(+)
create mode 100644 drivers/misc/Kconfig
create mode 100644 drivers/misc/Makefile
create mode 100644 drivers/misc/jtag.c
create mode 100644 include/jtag.h
diff --git a/drivers/Kconfig b/drivers/Kconfig
index c52c56a..c4d7962 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -12,6 +12,7 @@ source "drivers/video/Kconfig"
source "drivers/mci/Kconfig"
source "drivers/clk/Kconfig"
source "drivers/mfd/Kconfig"
+source "drivers/misc/Kconfig"
source "drivers/led/Kconfig"
source "drivers/eeprom/Kconfig"
source "drivers/input/Kconfig"
diff --git a/drivers/Makefile b/drivers/Makefile
index 3aefc12..8e692cb 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -15,3 +15,4 @@ obj-$(CONFIG_LED) += led/
obj-y += eeprom/
obj-$(CONFIG_PWM) += pwm/
obj-y += input/
+obj-y += misc/
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
new file mode 100644
index 0000000..122e065
--- /dev/null
+++ b/drivers/misc/Kconfig
@@ -0,0 +1,27 @@
+#
+# Misc strange devices
+#
+
+menuconfig MISC_DEVICES
+ bool "Misc devices "
+ default y
+ ---help---
+ Say Y here to get to see options for device drivers from various
+ different categories. This option alone does not add any kernel code.
+
+ If you say N, all options in this submenu will be skipped and
disabled.
+
+if MISC_DEVICES
+
+config JTAG
+ tristate "Jtag Bitbang driver"
+ default n
+ ---help---
+ Controls jtag chains connected to I/O pins
+
+ This driver can also be built as a module. If so, the module
+ will be called jtag.
+
+ If unsure, say N.
+
+endif # MISC_DEVICES
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
new file mode 100644
index 0000000..b085577
--- /dev/null
+++ b/drivers/misc/Makefile
@@ -0,0 +1,5 @@
+#
+# Makefile for misc devices that really don't fit anywhere else.
+#
+
+obj-$(CONFIG_JTAG) += jtag.o
diff --git a/drivers/misc/jtag.c b/drivers/misc/jtag.c
new file mode 100644
index 0000000..1bd927b
--- /dev/null
+++ b/drivers/misc/jtag.c
@@ -0,0 +1,395 @@
+/*
+ * drivers/misc/jtag.c - More infos in include/jtag.h
+ *
+ * Written Aug 2009 by Davide Rizzo <elpa.ri...@gmail.com>
+ *
+ * Ported to barebox Jul 2012 by
+ * Wjatscheslaw Stoljarski <wjatscheslaw.stoljar...@kiwigrid.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <fs.h>
+#include <errno.h>
+#include <linux/list.h>
+#include <jtag.h>
+#include <gpio.h>
+#include <driver.h>
+#include <malloc.h>
+#include <common.h>
+#include <init.h>
+#include <ioctl.h>
+#include <io.h>
+
+#define VERSION_MAJ 1
+#define VERSION_MIN 0
+
+/* Max devices in the jtag chain */
+#define MAX_DEVICES 16
+
+static LIST_HEAD(jtag_device_list);
+
+struct jtag_info {
+ struct jtag_platdata *pdata;
+ struct cdev cdev;
+ unsigned int devices; /* Number of devices found in the jtag chain */
+ struct list_head device_entry;
+ /* Instruction register length of every device in the chain */
+ unsigned int ir_len[]; /* [devices] */
+};
+
+static const unsigned long bypass = 0xFFFFFFFF;
+
+static void pulseTMS0(const struct jtag_platdata *pdata)
+{
+ gpio_set_value(pdata->pin_tms, 0);
+ gpio_set_value(pdata->pin_tclk, 0);
+ gpio_set_value(pdata->pin_tclk, 1);
+}
+
+static void pulseTMS1(const struct jtag_platdata *pdata)
+{
+ gpio_set_value(pdata->pin_tms, 1);
+ gpio_set_value(pdata->pin_tclk, 0);
+ gpio_set_value(pdata->pin_tclk, 1);
+}
+
+static void jtag_reset(const struct jtag_platdata *pdata)
+{
+ gpio_set_value(pdata->pin_tms, 1);
+ gpio_set_value(pdata->pin_tclk, 0);
+ gpio_set_value(pdata->pin_tclk, 1);
+ gpio_set_value(pdata->pin_tclk, 0);
+ gpio_set_value(pdata->pin_tclk, 1);
+ gpio_set_value(pdata->pin_tclk, 0);
+ gpio_set_value(pdata->pin_tclk, 1);
+ gpio_set_value(pdata->pin_tclk, 0);
+ gpio_set_value(pdata->pin_tclk, 1);
+ gpio_set_value(pdata->pin_tclk, 0);
+ gpio_set_value(pdata->pin_tclk, 1);
+}
+
+static void jtag_output(const struct jtag_platdata *pdata,
+ const unsigned long *data, unsigned int bitlen, int notlast)
+{
+ unsigned int a;
+ unsigned long mask;
+ gpio_set_value(pdata->pin_tms, 0);
+ while (bitlen > 0) {
+ for (a = *data++, mask = 0x00000001; mask != 0 && bitlen > 0;
+ mask <<= 1, bitlen--) {
+ gpio_set_value(pdata->pin_tdo, (a & mask) ? 1 : 0);
+ if ((bitlen == 1) && !notlast)
+ gpio_set_value(pdata->pin_tms, 1);
+ gpio_set_value(pdata->pin_tclk, 0);
+ gpio_set_value(pdata->pin_tclk, 1);
+ }
+ }
+}
+
+static int jtag_ioctl(struct cdev *inode, int cmd, void *arg)
+{
+ int ret = 0;
+ struct jtag_info *info = (struct jtag_info *)inode->priv;
+ int devices = info->devices;
+ struct jtag_cmd *jcmd = (struct jtag_cmd *)arg;
+ struct jtag_platdata *pdata = info->pdata;
+
+ if (_IOC_TYPE(cmd) != JTAG_IOC_MAGIC) return -ENOTTY;
+ if (_IOC_NR(cmd) > JTAG_IOC_MAXNR) return -ENOTTY;
+
+ switch (cmd) {
+
+ case JTAG_GET_DEVICES:
+ /* Returns how many devices found in the chain */
+ ret = info->devices;
+ break;
+
+ case JTAG_GET_ID:
+ /* Returns ID register of selected device */
+ if ((((struct jtag_rd_id *)arg)->device < 0) ||
+ (((struct jtag_rd_id *)arg)->device >= devices)) {
+ ret = -EINVAL;
+ break;
+ }
+ jtag_reset(pdata);
+ pulseTMS0(pdata);
+ pulseTMS1(pdata);
+ pulseTMS0(pdata);
+ pulseTMS0(pdata);
+ while (devices-- > 0) {
+ unsigned long id = 0;
+ pulseTMS0(pdata);
+ if (gpio_get_value(pdata->pin_tdi)) {
+ unsigned long mask;
+ for (id = 1, mask = 0x00000002; (mask != 0);
+ mask <<= 1) {
+ pulseTMS0(pdata);
+ if (gpio_get_value(pdata->pin_tdi))
+ id |= mask;
+ }
+ }
+ if (devices == ((struct jtag_rd_id *)arg)->device) {
+ ((struct jtag_rd_id *)arg)->id = id;
+ ret = 0;
+ break;
+ }
+ }
+ jtag_reset(pdata);
+ break;
+
+ case JTAG_SET_IR_LENGTH:
+ /* Sets up IR length of one device */
+ if ((jcmd->device >= 0) && (jcmd->device < devices))
+ info->ir_len[jcmd->device] = jcmd->bitlen;
+ else
+ ret = -EINVAL;
+ break;
+
+ case JTAG_RESET:
+ /* Resets all JTAG states */
+ jtag_reset(pdata);
+ break;
+
+ case JTAG_IR_WR:
+ /* Writes Instruction Register
+ If device == -1 writes same Instruction Register in all devices
+ If device >= 0 writes Instruction Register in selected device
+ and loads BYPASS instruction in all others */
+ if ((jcmd->device < -1) || (jcmd->device >= devices)) {
+ ret = -EINVAL;
+ break;
+ }
+ pulseTMS0(pdata);
+ pulseTMS1(pdata);
+ pulseTMS1(pdata);
+ pulseTMS0(pdata);
+ pulseTMS0(pdata);
+ while (devices-- > 0) {
+ if ((jcmd->device == -1) || (jcmd->device == devices))
+ /* Loads desired instruction */
+ jtag_output(pdata, jcmd->data,
+ info->ir_len[devices], devices);
+ else
+ /* Loads BYPASS instruction */
+ jtag_output(pdata, &bypass,
+ info->ir_len[devices], devices);
+ }
+ pulseTMS1(pdata);
+ pulseTMS0(pdata);
+ break;
+
+ case JTAG_DR_WR:
+ /* Writes Data Register of all devices
+ If device == -1 writes same Data Register in all devices
+ If device >= 0 writes Data Register in selected device
+ and loads BYPASS instruction in all others */
+ if ((jcmd->device < -1) || (jcmd->device >= devices)) {
+ ret = -EINVAL;
+ break;
+ }
+ pulseTMS0(pdata);
+ pulseTMS1(pdata);
+ pulseTMS0(pdata);
+ pulseTMS0(pdata);
+ while (devices-- > 0) {
+ if ((jcmd->device == -1) || (devices == jcmd->device))
+ /* Loads desired data */
+ jtag_output(pdata, jcmd->data, jcmd->bitlen,
+ devices);
+ else
+ /* Loads 1 dummy bit in BYPASS data register */
+ jtag_output(pdata, &bypass, 1, devices);
+ }
+ pulseTMS1(pdata);
+ pulseTMS0(pdata);
+ break;
+
+ case JTAG_DR_RD:
+ /* Reads data register of selected device */
+ if ((jcmd->device < 0) || (jcmd->device >= devices))
+ ret = -EINVAL;
+ else {
+ unsigned long mask;
+ int bitlen = jcmd->bitlen;
+ unsigned long *data = jcmd->data;
+ pulseTMS0(pdata);
+ pulseTMS1(pdata);
+ pulseTMS0(pdata);
+ pulseTMS0(pdata);
+ devices -= (jcmd->device + 1);
+ while (devices-- > 0)
+ pulseTMS0(pdata);
+ while (bitlen > 0) {
+ for (*data = 0, mask = 0x00000001;
+ (mask != 0) && (bitlen > 0);
+ mask <<= 1, bitlen--) {
+ if (bitlen == 1)
+ pulseTMS1(pdata);
+ else
+ pulseTMS0(pdata);
+ if (gpio_get_value(pdata->pin_tdi))
+ *data |= mask;
+ }
+ data++;
+ }
+ pulseTMS1(pdata);
+ pulseTMS0(pdata);
+ }
+ break;
+
+ case JTAG_CLK:
+ /* Generates arg clock pulses */
+ gpio_set_value(pdata->pin_tms, 0);
+ while ((*(unsigned int *) arg)--) {
+ gpio_set_value(pdata->pin_tclk, 0);
+ gpio_set_value(pdata->pin_tclk, 1);
+ }
+ break;
+
+ default:
+ ret = -EFAULT;
+ }
+
+ return ret;
+}
+
+struct file_operations jtag_operations = {
+ .ioctl = jtag_ioctl,
+};
+
+static int jtag_probe(struct device_d *pdev)
+{
+ int i, ret;
+ struct jtag_info *info;
+ struct jtag_platdata *pdata = pdev->platform_data;
+
+ /* Setup gpio pins */
+ gpio_direction_output(pdata->pin_tms, 0);
+ gpio_direction_output(pdata->pin_tclk, 1);
+ gpio_direction_output(pdata->pin_tdo, 0);
+ gpio_direction_input(pdata->pin_tdi);
+ if (pdata->use_pin_trst) {
+ /* Keep fixed at 1 because some devices in the chain could
+ not use it, to reset chain use jtag_reset() */
+ gpio_direction_output(pdata->pin_trst, 1);
+ }
+
+ /* Find how many devices in chain */
+ jtag_reset(pdata);
+ pulseTMS0(pdata);
+ pulseTMS1(pdata);
+ pulseTMS1(pdata);
+ pulseTMS0(pdata);
+ pulseTMS0(pdata);
+ gpio_set_value(pdata->pin_tdo, 1);
+ /* Fills all IR with bypass instruction */
+ for (i = 0; i < 32 * MAX_DEVICES; i++)
+ pulseTMS0(pdata);
+ pulseTMS1(pdata);
+ pulseTMS1(pdata);
+ pulseTMS1(pdata);
+ pulseTMS0(pdata);
+ pulseTMS0(pdata);
+ gpio_set_value(pdata->pin_tdo, 0);
+ /* Fills all 1-bit bypass register with 0 */
+ for (i = 0; i < MAX_DEVICES + 2; i++)
+ pulseTMS0(pdata);
+ gpio_set_value(pdata->pin_tdo, 1);
+ /* Counts chain's bit length */
+ for (i = 0; i < MAX_DEVICES + 1; i++) {
+ pulseTMS0(pdata);
+ if (gpio_get_value(pdata->pin_tdi))
+ break;
+ }
+ dev_notice(pdev, "%d devices found in chain\n", i);
+
+ /* Allocate structure with chain specific infos */
+ info = xzalloc(sizeof(struct jtag_info) + sizeof(info->ir_len[0]) * i);
+ if (!info) {
+ dev_err(pdev, "out of kernel memory\n");
+ return -ENOMEM;
+ }
+ info->devices = i;
+ INIT_LIST_HEAD(&info->device_entry);
+ list_add(&info->device_entry, &jtag_device_list);
+ info->pdata = pdata;
+ pdev->priv = info;
+
+ info->cdev.name = JTAG_NAME;
+ info->cdev.dev = pdev;
+ info->cdev.ops = &jtag_operations;
+ info->cdev.priv = info;
+ ret = devfs_create(&info->cdev);
+
+ if (ret)
+ goto fail_devfs_create;
+
+ return 0;
+
+fail_devfs_create:
+ pdev->priv = NULL;
+ free(info);
+ return ret;
+}
+
+static void jtag_info(struct device_d *pdev)
+{
+ int dn, ret;
+ struct jtag_rd_id jid;
+ struct jtag_info *info = pdev->priv;
+
+ printf(" JTAG:\n");
+ printf(" Devices found: %d\n", info->devices);
+ for(dn = 0; dn < info->devices; dn++) {
+ jid.device = dn;
+ ret = jtag_ioctl(&info->cdev, JTAG_GET_ID, &jid);
+ printf(" Device number: %d\n", dn);
+ if ( ret == -1 )
+ printf(" JTAG_GET_ID failed: %s\n", strerror(errno));
+ else
+ printf(" ID: 0x%lX\n", jid.id);
+ }
+}
+
+static void jtag_remove(struct device_d *pdev)
+{
+ struct jtag_info *info = (struct jtag_info *) pdev->priv;
+
+ list_del(&info->device_entry);
+ devfs_remove(&info->cdev);
+ pdev->priv = NULL;
+ free(info);
+ dev_notice(pdev, "Device removed\n");
+}
+
+static struct driver_d jtag_driver = {
+ .name = JTAG_NAME,
+ .probe = jtag_probe,
+ .remove = jtag_remove,
+ .info = jtag_info,
+};
+
+static int jtag_module_init(void)
+{
+ return register_driver(&jtag_driver);
+}
+
+device_initcall(jtag_module_init);
+
+MODULE_AUTHOR("Davide Rizzo <elpa.ri...@gmail.com>");
+MODULE_AUTHOR("Wjatscheslaw Stoljarski
<wjatscheslaw.stoljar...@kiwigrid.com>");
+MODULE_DESCRIPTION("JTAG bitbang driver");
+MODULE_LICENSE("GPL");
diff --git a/include/jtag.h b/include/jtag.h
new file mode 100644
index 0000000..d8f0606
--- /dev/null
+++ b/include/jtag.h
@@ -0,0 +1,113 @@
+/*
+ * include/linux/jtag.h
+ *
+ * Written Aug 2009 by Davide Rizzo <elpa.ri...@gmail.com>
+ * Ported to barebox Jul 2012 by
+ * Wjatscheslaw Stoljarski <wjatscheslaw.stoljar...@kiwigrid.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/*
+ * This driver manages one or more jtag chains controlled by host pins.
+ * Jtag chains must be defined during setup using jtag_platdata structs.
+ * All operations must be done from user programs using ioctls to /dev/jtag
+ * Typical operation sequence is:
+ * - open() the device (normally /dev/jtag)
+ * - ioctl JTAG_GET_DEVICES reads how many devices in the chain
+ * (repeat for each chip in the chain)
+ * - ioctl JTAG_GET_ID identifies the chip
+ * - ioctl JTAG_SET_IR_LENGTH sets the instruction register length
+ * Before accessing the data registers, instruction registers' lenghtes
+ * MUST be programmed for all chips.
+ * After this initialization, you can execute JTAG_IR_WR, JTAG_DR_RD,
JTAG_DR_WR
+ * commands in any sequence.
+ */
+
+#ifndef __JTAG_H__
+#define __JTAG_H__
+
+#ifdef __KERNEL__
+/* Controller's pin_tdi must be connected to last device's pin_tdo */
+/* Controller's pin_tdo must be connected to first device's pin_tdi */
+struct jtag_platdata {
+ unsigned int pin_tclk;
+ unsigned int pin_tms;
+ unsigned int pin_tdi;
+ unsigned int pin_tdo;
+ unsigned int pin_trst;
+ int use_pin_trst;
+};
+#endif /* __KERNEL__ */
+
+#define JTAG_NAME "jtag"
+
+/* structures used for passing arguments to ioctl */
+
+struct jtag_rd_id {
+ int device; /* Device in the chain */
+ unsigned long id;
+};
+
+struct jtag_cmd {
+ int device; /* Device in the chain (-1 = all devices) */
+ unsigned int bitlen; /* Bit length of the register to be transfered */
+ unsigned long *data; /* Data to be transfered */
+};
+
+/* Use 'j' as magic number */
+#define JTAG_IOC_MAGIC 'j'
+
+/* ioctl commands */
+
+/* Resets jtag chain status, arg is ignored */
+#define JTAG_RESET _IO(JTAG_IOC_MAGIC, 0)
+
+/* Returns the number of devices in the jtag chain, arg is ignored. */
+#define JTAG_GET_DEVICES _IO(JTAG_IOC_MAGIC, 1)
+
+/* arg must point to a jtag_rd_id structure.
+ Fills up the id field with ID of selected device */
+#define JTAG_GET_ID _IOR(JTAG_IOC_MAGIC, 2, struct jtag_rd_id)
+
+/* arg must point to a struct jtag_cmd.
+ Programs the Instruction Register length of specified device at
bitlen value.
+ *data is ignored. */
+#define JTAG_SET_IR_LENGTH _IOW(JTAG_IOC_MAGIC, 3, struct jtag_rd_id)
+
+/* arg must point to a struct jtag_cmd.
+ Writes *data in the Instruction Register of selected device, and BYPASS
+ instruction into Instruction Registers of all other devices in the
chain.
+ If device == -1, the Instruction Registers of all devices are programmed
+ to the same value.
+ bitlen is always ignored, before using this command you have to
program all
+ Instruction Register's lengthes with JTAG_SET_IR_LENGTH command. */
+#define JTAG_IR_WR _IOW(JTAG_IOC_MAGIC, 4, struct jtag_cmd)
+
+/* arg must point to a struct jtag_cmd.
+ Reads data register of selected device, with length bitlen */
+#define JTAG_DR_RD _IOR(JTAG_IOC_MAGIC, 5, struct jtag_cmd)
+
+/* arg must point to a struct jtag_cmd.
+ Writes data register of selected device, with length bitlen.
+ If device == -1, writes same data on all devices. */
+#define JTAG_DR_WR _IOW(JTAG_IOC_MAGIC, 6, struct jtag_cmd)
+
+/* Generates arg pulses on TCLK pin */
+#define JTAG_CLK _IOW(JTAG_IOC_MAGIC, 7, unsigned int)
+
+#define JTAG_IOC_MAXNR 9
+
+#endif /* __JTAG_H__ */
--
1.7.9.5
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