Initial patch for JTAG driver JTAG class driver provide infrastructure to support hardware/software JTAG platform drivers. It provide user layer API interface for flashing and debugging external devices which equipped with JTAG interface using standard transactions. Driver exposes set of IOCTL to user space for: - XFER: - SIR (Scan Instruction Register, IEEE 1149.1 Data Register scan); - SDR (Scan Data Register, IEEE 1149.1 Instruction Register scan); - RUNTEST (Forces the IEEE 1149.1 bus to a run state for a specified number of clocks). - SIOCFREQ/GIOCFREQ for setting and reading JTAG frequency. Driver core provides set of internal APIs for allocation and registration: - jtag_register; - jtag_unregister; - jtag_alloc; - jtag_free; Platform driver on registration with jtag-core creates the next entry in dev folder: /dev/jtagX Signed-off-by: Oleksandr Shamray <oleksandrs@xxxxxxxxxxxx> Signed-off-by: Jiri Pirko <jiri@xxxxxxxxxxxx> Acked-by: Philippe Ombredanne <pombredanne@xxxxxxxx> --- v19->v20 Comments pointed by Randy Dunlap <rdunlap@xxxxxxxxxxxxx> - Fix JTAG dirver help in Kconfig Notifications from kbuild test robot <lkp@xxxxxxxxx> - fix incompatible type casts v18->v19 Comments pointed by Julia Cartwright <juliac@xxxxxxxxxxxx> - Fix memory leak on jtag_alloc exit v17->v18 Comments pointed by Julia Cartwright <juliac@xxxxxxxxxxxx> - Change to return -EOPNOTSUPP in case of error in JTAG_GIOCFREQ - Add ops callbacks check to jtag_alloc - Add err check for copy_to_user - Move the kfree() above the if (err) in JTAG_IOCXFER - remove unnecessary check for error after put_user - add padding to struct jtag_xfer v16->v17 Comments pointed by Julia Cartwright <juliac@xxxxxxxxxxxx> - Fix memory allocation on jtag alloc - Move out unnecessary form lock on jtag open - Rework jtag register behavior v15->v16 Commen ts pointed by Florian Fainelli <f.fainelli@xxxxxxxxx> - move check jtag->ops->* in ioctl before get_user() - change error type -EINVAL --> -EBUSY on open already opened jtag - remove unnecessary ARCH_DMA_MINALIGN flag from kzalloc - remove define ARCH_DMA_MINALIGN v14->v15 v13->v14 Comments pointed by Philippe Ombredanne <pombredanne@xxxxxxxx> - Change style of head block comment from /**/ to // v12->v13 Comments pointed by Philippe Ombredanne <pombredanne@xxxxxxxx> - Change jtag.c licence type to SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note and reorder line with license in description v11->v12 Comments pointed by Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> - Change jtag.h licence type to SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note and reorder line with license in description Chip Bilbrey <chip@xxxxxxxxxxx> - Remove Apeed reference from uapi jtag.h header - Remove access mode from xfer and idle transactions - Add new ioctl JTAG_SIOCMODE for set hw mode - Add only one open per JTAG port blocking with mutex blocking v10->v11 Notifications from kbuild test robot <lkp@xxxxxxxxx> - include types.h headeri to jtag.h - fix incompatible type of xfer callback - remove rdundant class defination - Fix return order in case of xfer error V9->v10 Comments pointed by Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> - remove unnecessary alignment for pirv data - move jtag_copy_to_user and jtag_copy_from_user code just to ioctl - move int jtag_run_test_idle_op and jtag_xfer_op code just to ioctl - change return error codes to more applicable - add missing error checks - fix error check order in ioctl - remove unnecessary blank lines - add param validation to ioctl - remove compat_ioctl - remove only one open per JTAG port blocking. User will care about this. - Fix idr memory leak on jtag_exit - change cdev device type to misc V8->v9 Comments pointed by Arnd Bergmann <arnd@xxxxxxxx> - use get_user() instead of __get_user(). - change jtag->open type from int to atomic_t - remove spinlock on jtg_open - remove mutex on jtag_register - add unregister_chrdev_region on jtag_init err - add unregister_chrdev_region on jtag_exit - remove unnecessary pointer casts - add *data parameter to xfer function prototype v7->v8 Comments pointed by Moritz Fischer <moritz.fischer@xxxxxxxxx> - Fix misspelling s/friver/driver v6->v7 Notifications from kbuild test robot <lkp@xxxxxxxxx> - Remove include asm/types.h from jtag.h - Add include <linux/types.h> to jtag.c v5->v6 v4->v5 v3->v4 Comments pointed by Arnd Bergmann <arnd@xxxxxxxx> - change transaction pointer tdio type to __u64 - change internal status type from enum to __u32 - reorder jtag_xfer members to avoid the implied padding - add __packed attribute to jtag_xfer and jtag_run_test_idle v2->v3 Notifications from kbuild test robot <lkp@xxxxxxxxx> - Change include path to <linux/types.h> in jtag.h v1->v2 Comments pointed by Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> - Change license type from GPLv2/BSD to GPLv2 - Change type of variables which crossed user/kernel to __type - Remove "default n" from Kconfig Comments pointed by Andrew Lunn <andrew@xxxxxxx> - Change list_add_tail in jtag_unregister to list_del Comments pointed by Neil Armstrong <narmstrong@xxxxxxxxxxxx> - Add SPDX-License-Identifier instead of license text Comments pointed by Arnd Bergmann <arnd@xxxxxxxx> - Change __copy_to_user to memdup_user - Change __put_user to put_user - Change type of variables to __type for compatible 32 and 64-bit systems - Add check for maximum xfer data size - Change lookup data mechanism to get jtag data from inode - Add .compat_ioctl to file ops - Add mem alignment for jtag priv data Comments pointed by Tobias Klauser <tklauser@xxxxxxxxxx> - Change function names to avoid match with variable types - Fix description for jtag_ru_test_idle in uapi jtag.h - Fix misprints IDEL/IDLE, trough/through --- Documentation/ioctl/ioctl-number.txt | 2 + MAINTAINERS | 10 ++ drivers/Kconfig | 2 + drivers/Makefile | 1 + drivers/jtag/Kconfig | 18 +++ drivers/jtag/Makefile | 1 + drivers/jtag/jtag.c | 274 ++++++++++++++++++++++++++++++++++ include/linux/jtag.h | 41 +++++ include/uapi/linux/jtag.h | 105 +++++++++++++ 9 files changed, 454 insertions(+), 0 deletions(-) create mode 100644 drivers/jtag/Kconfig create mode 100644 drivers/jtag/Makefile create mode 100644 drivers/jtag/jtag.c create mode 100644 include/linux/jtag.h create mode 100644 include/uapi/linux/jtag.h diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt index 7f7413e..c5548b5 100644 --- a/Documentation/ioctl/ioctl-number.txt +++ b/Documentation/ioctl/ioctl-number.txt @@ -318,6 +318,8 @@ Code Seq#(hex) Include File Comments 0xB0 all RATIO devices in development: <mailto:vgo@xxxxxxxx> 0xB1 00-1F PPPoX <mailto:mostrows@xxxxxxxxxxxxxxxxx> +0xB2 00-0f linux/jtag.h JTAG driver + <mailto:oleksandrs@xxxxxxxxxxxx> 0xB3 00 linux/mmc/ioctl.h 0xB4 00-0F linux/gpio.h <mailto:linux-gpio@xxxxxxxxxxxxxxx> 0xB5 00-0F uapi/linux/rpmsg.h <mailto:linux-remoteproc@xxxxxxxxxxxxxxx> diff --git a/MAINTAINERS b/MAINTAINERS index 79bb02f..2fd22d6 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7610,6 +7610,16 @@ L: linux-serial@xxxxxxxxxxxxxxx S: Maintained F: drivers/tty/serial/jsm/ +JTAG SUBSYSTEM +M: Oleksandr Shamray <oleksandrs@xxxxxxxxxxxx> +M: Vadim Pasternak <vadimp@xxxxxxxxxxxx> +S: Maintained +F: include/linux/jtag.h +F: include/uapi/linux/jtag.h +F: drivers/jtag/ +F: Documentation/devicetree/bindings/jtag/ +F: Documentation/ABI/testing/jtag-cdev + K10TEMP HARDWARE MONITORING DRIVER M: Clemens Ladisch <clemens@xxxxxxxxxx> L: linux-hwmon@xxxxxxxxxxxxxxx diff --git a/drivers/Kconfig b/drivers/Kconfig index 95b9ccc..bb71e48 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -217,4 +217,6 @@ source "drivers/siox/Kconfig" source "drivers/slimbus/Kconfig" +source "drivers/jtag/Kconfig" + endmenu diff --git a/drivers/Makefile b/drivers/Makefile index 24cd470..c92636b 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -185,3 +185,4 @@ obj-$(CONFIG_TEE) += tee/ obj-$(CONFIG_MULTIPLEXER) += mux/ obj-$(CONFIG_UNISYS_VISORBUS) += visorbus/ obj-$(CONFIG_SIOX) += siox/ +obj-$(CONFIG_JTAG) += jtag/ diff --git a/drivers/jtag/Kconfig b/drivers/jtag/Kconfig new file mode 100644 index 0000000..ba72a2b --- /dev/null +++ b/drivers/jtag/Kconfig @@ -0,0 +1,18 @@ +menuconfig JTAG + tristate "JTAG support" + help + This provides basic core functionality support for JTAG class devices + Hardware that is equipped with a JTAG microcontroller can be + supported by using this driver's interfaces. + This driver exposes a set of IOCTL to the user space for + another commands: + SDR: (Scan Data Register) Performs an IEEE 1149.1 Data Register scan + SIR: (Scan Instruction Register) Performs an IEEE 1149.1 Instruction + Register scan. + RUNTEST: Forces the IEEE 1149.1 bus to a run state for a specified + number of clocks or a specified time period. + + If you want this support, you should say Y here. + + To compile this driver as a module, choose M here: the module will + be called jtag. diff --git a/drivers/jtag/Makefile b/drivers/jtag/Makefile new file mode 100644 index 0000000..af37493 --- /dev/null +++ b/drivers/jtag/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_JTAG) += jtag.o diff --git a/drivers/jtag/jtag.c b/drivers/jtag/jtag.c new file mode 100644 index 0000000..84c29c8 --- /dev/null +++ b/drivers/jtag/jtag.c @@ -0,0 +1,274 @@ +// SPDX-License-Identifier: GPL-2.0-only +// drivers/jtag/jtag.c +// +// Copyright (c) 2018 Mellanox Technologies. All rights reserved. +// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@xxxxxxxxxxxx> + +#include <linux/cdev.h> +#include <linux/device.h> +#include <linux/jtag.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/rtnetlink.h> +#include <linux/spinlock.h> +#include <linux/types.h> +#include <uapi/linux/jtag.h> + +#define JTAG_NAME "jtag0" +#define MAX_JTAG_NAME_LEN (sizeof("jtag") + 5) + +struct jtag { + struct miscdevice miscdev; + struct device *dev; + const struct jtag_ops *ops; + int id; + bool opened; + struct mutex open_lock; + unsigned long priv[0]; +}; + +static DEFINE_IDA(jtag_ida); + +void *jtag_priv(struct jtag *jtag) +{ + return jtag->priv; +} +EXPORT_SYMBOL_GPL(jtag_priv); + +static long jtag_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct jtag *jtag = file->private_data; + struct jtag_run_test_idle idle; + struct jtag_xfer xfer; + u8 *xfer_data; + u32 data_size; + u32 value; + int err; + + if (!arg) + return -EINVAL; + + switch (cmd) { + case JTAG_GIOCFREQ: + if (!jtag->ops->freq_get) + return -EOPNOTSUPP; + + err = jtag->ops->freq_get(jtag, &value); + if (err) + break; + + if (put_user(value, (__u32 __user *)arg)) + err = -EFAULT; + break; + + case JTAG_SIOCFREQ: + if (!jtag->ops->freq_set) + return -EOPNOTSUPP; + + if (get_user(value, (__u32 __user *)arg)) + return -EFAULT; + if (value == 0) + return -EINVAL; + + err = jtag->ops->freq_set(jtag, value); + break; + + case JTAG_IOCRUNTEST: + if (copy_from_user(&idle, (const void __user *)arg, + sizeof(struct jtag_run_test_idle))) + return -EFAULT; + + if (idle.endstate > JTAG_STATE_PAUSEDR) + return -EINVAL; + + err = jtag->ops->idle(jtag, &idle); + break; + + case JTAG_IOCXFER: + if (copy_from_user(&xfer, (const void __user *)arg, + sizeof(struct jtag_xfer))) + return -EFAULT; + + if (xfer.length >= JTAG_MAX_XFER_DATA_LEN) + return -EINVAL; + + if (xfer.type > JTAG_SDR_XFER) + return -EINVAL; + + if (xfer.direction > JTAG_WRITE_XFER) + return -EINVAL; + + if (xfer.endstate > JTAG_STATE_PAUSEDR) + return -EINVAL; + + data_size = DIV_ROUND_UP(xfer.length, BITS_PER_BYTE); + xfer_data = memdup_user(u64_to_user_ptr(xfer.tdio), data_size); + + if (IS_ERR(xfer_data)) + return -EFAULT; + + err = jtag->ops->xfer(jtag, &xfer, xfer_data); + if (err) { + kfree(xfer_data); + return -EFAULT; + } + + err = copy_to_user(u64_to_user_ptr(xfer.tdio), + (void *)(xfer_data), data_size); + kfree(xfer_data); + if (err) + return -EFAULT; + + if (copy_to_user((void __user *)arg, (void *)&xfer, + sizeof(struct jtag_xfer))) + return -EFAULT; + break; + + case JTAG_GIOCSTATUS: + err = jtag->ops->status_get(jtag, &value); + if (err) + break; + + err = put_user(value, (__u32 __user *)arg); + break; + case JTAG_SIOCMODE: + if (get_user(value, (__u32 __user *)arg)) + return -EFAULT; + if (value == 0) + return -EINVAL; + + err = jtag->ops->mode_set(jtag, value); + break; + + default: + return -EINVAL; + } + return err; +} + +static int jtag_open(struct inode *inode, struct file *file) +{ + struct jtag *jtag = container_of(file->private_data, struct jtag, + miscdev); + + if (mutex_lock_interruptible(&jtag->open_lock)) + return -ERESTARTSYS; + + if (jtag->opened) { + mutex_unlock(&jtag->open_lock); + return -EBUSY; + } + jtag->opened = true; + mutex_unlock(&jtag->open_lock); + + nonseekable_open(inode, file); + file->private_data = jtag; + return 0; +} + +static int jtag_release(struct inode *inode, struct file *file) +{ + struct jtag *jtag = file->private_data; + + mutex_lock(&jtag->open_lock); + jtag->opened = false; + mutex_unlock(&jtag->open_lock); + return 0; +} + +static const struct file_operations jtag_fops = { + .owner = THIS_MODULE, + .open = jtag_open, + .release = jtag_release, + .llseek = noop_llseek, + .unlocked_ioctl = jtag_ioctl, +}; + +struct jtag *jtag_alloc(size_t priv_size, const struct jtag_ops *ops) +{ + struct jtag *jtag; + + if (!ops) + return NULL; + + if (!ops->idle || !ops->mode_set || !ops->status_get || !ops->xfer) + return NULL; + + jtag = kzalloc(sizeof(*jtag) + priv_size, GFP_KERNEL); + if (!jtag) + return NULL; + + jtag->ops = ops; + return jtag; +} +EXPORT_SYMBOL_GPL(jtag_alloc); + +void jtag_free(struct jtag *jtag) +{ + kfree(jtag); +} +EXPORT_SYMBOL_GPL(jtag_free); + +int jtag_register(struct jtag *jtag) +{ + char *name; + int err; + int id; + + id = ida_simple_get(&jtag_ida, 0, 0, GFP_KERNEL); + if (id < 0) + return id; + + jtag->id = id; + jtag->opened = false; + + name = kzalloc(MAX_JTAG_NAME_LEN, GFP_KERNEL); + if (!name) { + err = -ENOMEM; + goto err_jtag_alloc; + } + + err = snprintf(name, MAX_JTAG_NAME_LEN, "jtag%d", id); + if (err < 0) + goto err_jtag_name; + + mutex_init(&jtag->open_lock); + jtag->miscdev.fops = &jtag_fops; + jtag->miscdev.minor = MISC_DYNAMIC_MINOR; + jtag->miscdev.name = name; + + err = misc_register(&jtag->miscdev); + if (err) { + dev_err(jtag->dev, "Unable to register device\n"); + goto err_jtag_name; + } + return 0; + +err_jtag_name: + kfree(name); +err_jtag_alloc: + ida_simple_remove(&jtag_ida, id); + return err; +} +EXPORT_SYMBOL_GPL(jtag_register); + +void jtag_unregister(struct jtag *jtag) +{ + misc_deregister(&jtag->miscdev); + kfree(jtag->miscdev.name); + ida_simple_remove(&jtag_ida, jtag->id); +} +EXPORT_SYMBOL_GPL(jtag_unregister); + +static void __exit jtag_exit(void) +{ + ida_destroy(&jtag_ida); +} + +module_exit(jtag_exit); + +MODULE_AUTHOR("Oleksandr Shamray <oleksandrs@xxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Generic jtag support"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/jtag.h b/include/linux/jtag.h new file mode 100644 index 0000000..80a887f --- /dev/null +++ b/include/linux/jtag.h @@ -0,0 +1,41 @@ +// SPDX-License-Identifier: GPL-2.0 +// include/linux/jtag.h - JTAG class driver +// +// Copyright (c) 2018 Mellanox Technologies. All rights reserved. +// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@xxxxxxxxxxxx> + +#ifndef __JTAG_H +#define __JTAG_H + +#include <uapi/linux/jtag.h> + +#define jtag_u64_to_ptr(arg) ((void *)(uintptr_t)arg) + +#define JTAG_MAX_XFER_DATA_LEN 65535 + +struct jtag; +/** + * struct jtag_ops - callbacks for jtag control functions: + * + * @freq_get: get frequency function. Filled by device driver + * @freq_set: set frequency function. Filled by device driver + * @status_get: set status function. Filled by device driver + * @idle: set JTAG to idle state function. Filled by device driver + * @xfer: send JTAG xfer function. Filled by device driver + */ +struct jtag_ops { + int (*freq_get)(struct jtag *jtag, u32 *freq); + int (*freq_set)(struct jtag *jtag, u32 freq); + int (*status_get)(struct jtag *jtag, u32 *state); + int (*idle)(struct jtag *jtag, struct jtag_run_test_idle *idle); + int (*xfer)(struct jtag *jtag, struct jtag_xfer *xfer, u8 *xfer_data); + int (*mode_set)(struct jtag *jtag, u32 mode_mask); +}; + +void *jtag_priv(struct jtag *jtag); +int jtag_register(struct jtag *jtag); +void jtag_unregister(struct jtag *jtag); +struct jtag *jtag_alloc(size_t priv_size, const struct jtag_ops *ops); +void jtag_free(struct jtag *jtag); + +#endif /* __JTAG_H */ diff --git a/include/uapi/linux/jtag.h b/include/uapi/linux/jtag.h new file mode 100644 index 0000000..ecd02a0 --- /dev/null +++ b/include/uapi/linux/jtag.h @@ -0,0 +1,105 @@ +// SPDX-License-Identifier: GPL-2.0 +// include/uapi/linux/jtag.h - JTAG class driver uapi +// +// Copyright (c) 2018 Mellanox Technologies. All rights reserved. +// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@xxxxxxxxxxxx> + +#ifndef __UAPI_LINUX_JTAG_H +#define __UAPI_LINUX_JTAG_H + +#include <linux/types.h> +/* + * JTAG_XFER_HW_MODE: JTAG hardware mode. Used to set HW drived or bitbang + * mode. This is bitmask param of ioctl JTAG_SIOCMODE command + */ +#define JTAG_XFER_HW_MODE 1 + +/** + * enum jtag_endstate: + * + * @JTAG_STATE_IDLE: JTAG state machine IDLE state + * @JTAG_STATE_PAUSEIR: JTAG state machine PAUSE_IR state + * @JTAG_STATE_PAUSEDR: JTAG state machine PAUSE_DR state + */ +enum jtag_endstate { + JTAG_STATE_IDLE, + JTAG_STATE_PAUSEIR, + JTAG_STATE_PAUSEDR, +}; + +/** + * enum jtag_xfer_type: + * + * @JTAG_SIR_XFER: SIR transfer + * @JTAG_SDR_XFER: SDR transfer + */ +enum jtag_xfer_type { + JTAG_SIR_XFER, + JTAG_SDR_XFER, +}; + +/** + * enum jtag_xfer_direction: + * + * @JTAG_READ_XFER: read transfer + * @JTAG_WRITE_XFER: write transfer + */ +enum jtag_xfer_direction { + JTAG_READ_XFER, + JTAG_WRITE_XFER, +}; + +/** + * struct jtag_run_test_idle - forces JTAG state machine to + * RUN_TEST/IDLE state + * + * @reset: 0 - run IDLE/PAUSE from current state + * 1 - go through TEST_LOGIC/RESET state before IDLE/PAUSE + * @end: completion flag + * @tck: clock counter + * + * Structure represents interface to JTAG device for jtag idle + * execution. + */ +struct jtag_run_test_idle { + __u8 reset; + __u8 endstate; + __u8 tck; +}; + +/** + * struct jtag_xfer - jtag xfer: + * + * @type: transfer type + * @direction: xfer direction + * @length: xfer bits len + * @tdio : xfer data array + * @endir: xfer end state + * + * Structure represents interface to JTAG device for jtag sdr xfer + * execution. + */ +struct jtag_xfer { + __u8 type; + __u8 direction; + __u8 endstate; + __u8 padding; + __u32 length; + __u64 tdio; +}; + +/* ioctl interface */ +#define __JTAG_IOCTL_MAGIC 0xb2 + +#define JTAG_IOCRUNTEST _IOW(__JTAG_IOCTL_MAGIC, 0,\ + struct jtag_run_test_idle) +#define JTAG_SIOCFREQ _IOW(__JTAG_IOCTL_MAGIC, 1, unsigned int) +#define JTAG_GIOCFREQ _IOR(__JTAG_IOCTL_MAGIC, 2, unsigned int) +#define JTAG_IOCXFER _IOWR(__JTAG_IOCTL_MAGIC, 3, struct jtag_xfer) +#define JTAG_GIOCSTATUS _IOWR(__JTAG_IOCTL_MAGIC, 4, enum jtag_endstate) +#define JTAG_SIOCMODE _IOW(__JTAG_IOCTL_MAGIC, 5, unsigned int) + +#define JTAG_FIRST_MINOR 0 +#define JTAG_MAX_DEVICES 32 + +#endif /* __UAPI_LINUX_JTAG_H */ -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
