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* [PATCH 2/4] thermal: bcm2835: Stop using printk format %pCr
From: Geert Uytterhoeven @ 2018-06-01  9:28 UTC (permalink / raw)
  To: Jia-Ju Bai, Jonathan Corbet, Michael Turquette, Stephen Boyd,
	Zhang Rui, Eduardo Valentin, Eric Anholt, Stefan Wahren,
	Greg Kroah-Hartman
  Cc: Sergey Senozhatsky, Petr Mladek, Linus Torvalds, Steven Rostedt,
	linux-doc, linux-clk, linux-pm, linux-serial, linux-arm-kernel,
	linux-renesas-soc, linux-kernel, Geert Uytterhoeven
In-Reply-To: <1527845302-12159-1-git-send-email-geert+renesas@glider.be>

Printk format "%pCr" will be removed soon, as clk_get_rate() must not be
called in atomic context.

Replace it by printing the variable that already holds the clock rate.
Note that calling clk_get_rate() is safe here, as the code runs in task
context.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/thermal/broadcom/bcm2835_thermal.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/thermal/broadcom/bcm2835_thermal.c b/drivers/thermal/broadcom/bcm2835_thermal.c
index a4d6a0e2e9938190..23ad4f9f21438e45 100644
--- a/drivers/thermal/broadcom/bcm2835_thermal.c
+++ b/drivers/thermal/broadcom/bcm2835_thermal.c
@@ -213,8 +213,8 @@ static int bcm2835_thermal_probe(struct platform_device *pdev)
 	rate = clk_get_rate(data->clk);
 	if ((rate < 1920000) || (rate > 5000000))
 		dev_warn(&pdev->dev,
-			 "Clock %pCn running at %pCr Hz is outside of the recommended range: 1.92 to 5MHz\n",
-			 data->clk, data->clk);
+			 "Clock %pCn running at %lu Hz is outside of the recommended range: 1.92 to 5MHz\n",
+			 data->clk, rate);
 
 	/* register of thermal sensor and get info from DT */
 	tz = thermal_zone_of_sensor_register(&pdev->dev, 0, data,
-- 
2.7.4

^ permalink raw reply related

* [PATCH 1/4] clk: renesas: cpg-mssr: Stop using printk format %pCr
From: Geert Uytterhoeven @ 2018-06-01  9:28 UTC (permalink / raw)
  To: Jia-Ju Bai, Jonathan Corbet, Michael Turquette, Stephen Boyd,
	Zhang Rui, Eduardo Valentin, Eric Anholt, Stefan Wahren,
	Greg Kroah-Hartman
  Cc: Petr Mladek, Sergey Senozhatsky, Geert Uytterhoeven, linux-doc,
	linux-pm, linux-kernel, Steven Rostedt, linux-renesas-soc,
	linux-serial, Linus Torvalds, linux-clk, linux-arm-kernel
In-Reply-To: <1527845302-12159-1-git-send-email-geert+renesas@glider.be>

Printk format "%pCr" will be removed soon, as clk_get_rate() must not be
called in atomic context.

Replace it by open-coding the operation.  This is safe here, as the code
runs in task context.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/clk/renesas/renesas-cpg-mssr.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/renesas/renesas-cpg-mssr.c b/drivers/clk/renesas/renesas-cpg-mssr.c
index 49e510691eeeab07..f4b013e9352d9efc 100644
--- a/drivers/clk/renesas/renesas-cpg-mssr.c
+++ b/drivers/clk/renesas/renesas-cpg-mssr.c
@@ -258,8 +258,9 @@ struct clk *cpg_mssr_clk_src_twocell_get(struct of_phandle_args *clkspec,
 		dev_err(dev, "Cannot get %s clock %u: %ld", type, clkidx,
 		       PTR_ERR(clk));
 	else
-		dev_dbg(dev, "clock (%u, %u) is %pC at %pCr Hz\n",
-			clkspec->args[0], clkspec->args[1], clk, clk);
+		dev_dbg(dev, "clock (%u, %u) is %pC at %lu Hz\n",
+			clkspec->args[0], clkspec->args[1], clk,
+			clk_get_rate(clk));
 	return clk;
 }
 
@@ -326,7 +327,7 @@ static void __init cpg_mssr_register_core_clk(const struct cpg_core_clk *core,
 	if (IS_ERR_OR_NULL(clk))
 		goto fail;
 
-	dev_dbg(dev, "Core clock %pC at %pCr Hz\n", clk, clk);
+	dev_dbg(dev, "Core clock %pC at %lu Hz\n", clk, clk_get_rate(clk));
 	priv->clks[id] = clk;
 	return;
 
@@ -392,7 +393,7 @@ static void __init cpg_mssr_register_mod_clk(const struct mssr_mod_clk *mod,
 	if (IS_ERR(clk))
 		goto fail;
 
-	dev_dbg(dev, "Module clock %pC at %pCr Hz\n", clk, clk);
+	dev_dbg(dev, "Module clock %pC at %lu Hz\n", clk, clk_get_rate(clk));
 	priv->clks[id] = clk;
 	priv->smstpcr_saved[clock->index / 32].mask |= BIT(clock->index % 32);
 	return;
-- 
2.7.4

^ permalink raw reply related

* [PATCH 0/4] lib/vsprintf: Remove atomic-unsafe support for printk format %pCr
From: Geert Uytterhoeven @ 2018-06-01  9:28 UTC (permalink / raw)
  To: Jia-Ju Bai, Jonathan Corbet, Michael Turquette, Stephen Boyd,
	Zhang Rui, Eduardo Valentin, Eric Anholt, Stefan Wahren,
	Greg Kroah-Hartman
  Cc: Sergey Senozhatsky, Petr Mladek, Linus Torvalds, Steven Rostedt,
	linux-doc, linux-clk, linux-pm, linux-serial, linux-arm-kernel,
	linux-renesas-soc, linux-kernel, Geert Uytterhoeven

	Hi all,

"%pCr" formats the current rate of a clock, and calls clk_get_rate().
The latter obtains a mutex, hence it must not be called from atomic
context.  As vsprintf() (and e.g. printk()) must be callable from any
context, it's better to remove support for this (rarely-used) format.

This patch series:
  - Changes all existing users of "%pCr" to print the result of
    clk_get_rate() directly, which is safe as they all do this in task
    context only,
  - Removes support for the "%pCr" printk format.

Note that any remaining out-of-tree users will start seeing the clock's
name printed instead of its rate.

Thanks for your comments!

Geert Uytterhoeven (4):
  clk: renesas: cpg-mssr: Stop using printk format %pCr
  thermal: bcm2835: Stop using printk format %pCr
  serial: sh-sci: Stop using printk format %pCr
  lib/vsprintf: Remove atomic-unsafe support for %pCr

 Documentation/core-api/printk-formats.rst  | 3 +--
 drivers/clk/renesas/renesas-cpg-mssr.c     | 9 +++++----
 drivers/thermal/broadcom/bcm2835_thermal.c | 4 ++--
 drivers/tty/serial/sh-sci.c                | 4 ++--
 lib/vsprintf.c                             | 3 ---
 5 files changed, 10 insertions(+), 13 deletions(-)

-- 
2.7.4

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds

^ permalink raw reply

* Re: [PATCH 15/19] net: qualcomm: MODULE_DEVICE_TABLE(serdev)
From: Stefan Wahren @ 2018-06-01  8:59 UTC (permalink / raw)
  To: Ricardo Ribalda Delgado, linux-kernel, linux-serial
  Cc: Lino Sanfilippo, David S . Miller, Rob Herring, Johan Hovold,
	netdev
In-Reply-To: <20180529131014.18641-16-ricardo.ribalda@gmail.com>

Hi Ricardo,


Am 29.05.2018 um 15:10 schrieb Ricardo Ribalda Delgado:
> Export serdev table to the module header, allowing module autoload via
> udev/modprobe.
>
> Cc: Lino Sanfilippo <LinoSanfilippo@gmx.de>
> Cc: David S. Miller <davem@davemloft.net>
> Cc: Stefan Wahren <stefan.wahren@i2se.com>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Johan Hovold <johan@kernel.org>
> Cc: netdev@vger.kernel.org
> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
> ---
>   drivers/net/ethernet/qualcomm/qca_uart.c | 7 +++++++
>   1 file changed, 7 insertions(+)
>
> diff --git a/drivers/net/ethernet/qualcomm/qca_uart.c b/drivers/net/ethernet/qualcomm/qca_uart.c
> index db6068cd7a1f..bb7aed805083 100644
> --- a/drivers/net/ethernet/qualcomm/qca_uart.c
> +++ b/drivers/net/ethernet/qualcomm/qca_uart.c
> @@ -405,6 +405,12 @@ static void qca_uart_remove(struct serdev_device *serdev)
>   	free_netdev(qca->net_dev);
>   }
>   
> +static struct serdev_device_id qca_uart_serdev_id[] = {
> +	{ QCAUART_DRV_NAME, },

i guess the id must be stable, so in case someone changes the driver 
name this has unexpected side effects?

Apart from that i'm fine with this patch.

Thanks
Stefan

> +	{},
> +};
> +MODULE_DEVICE_TABLE(serdev, qca_uart_serdev_id);
> +
>   static struct serdev_device_driver qca_uart_driver = {
>   	.probe = qca_uart_probe,
>   	.remove = qca_uart_remove,
> @@ -412,6 +418,7 @@ static struct serdev_device_driver qca_uart_driver = {
>   		.name = QCAUART_DRV_NAME,
>   		.of_match_table = of_match_ptr(qca_uart_of_match),
>   	},
> +	.id_table = qca_uart_serdev_id,
>   };
>   
>   module_serdev_device_driver(qca_uart_driver);

^ permalink raw reply

* Re: [PATCH v4 3/6] mfd: at91-usart: added mfd driver for usart
From: Rob Herring @ 2018-05-31  1:02 UTC (permalink / raw)
  To: Radu Pirea
  Cc: broonie, nicolas.ferre, alexandre.belloni, lee.jones,
	richard.genoud, mark.rutland, gregkh, linux-spi, linux-arm-kernel,
	linux-kernel, devicetree, linux-serial
In-Reply-To: <20180525171941.26766-4-radu.pirea@microchip.com>

On Fri, May 25, 2018 at 08:19:38PM +0300, Radu Pirea wrote:
> This mfd driver is just a wrapper over atmel_serial driver and
> spi-at91-usart driver. Selection of one of the drivers is based on a
> property from device tree. If the property is not specified, the default
> driver is atmel_serial.
> 
> Signed-off-by: Radu Pirea <radu.pirea@microchip.com>
> ---
>  drivers/mfd/Kconfig                  | 10 ++++
>  drivers/mfd/Makefile                 |  1 +
>  drivers/mfd/at91-usart.c             | 75 ++++++++++++++++++++++++++++

>  include/dt-bindings/mfd/at91-usart.h | 17 +++++++

This really should be part of the binding patch.

Acked-by: Rob Herring <robh@kernel.org>

>  4 files changed, 103 insertions(+)
>  create mode 100644 drivers/mfd/at91-usart.c
>  create mode 100644 include/dt-bindings/mfd/at91-usart.h

^ permalink raw reply

* Re: [PATCH v4 2/6] dt-bindings: add binding for atmel-usart in SPI mode
From: Rob Herring @ 2018-05-31  1:00 UTC (permalink / raw)
  To: Radu Pirea
  Cc: broonie, nicolas.ferre, alexandre.belloni, lee.jones,
	richard.genoud, mark.rutland, gregkh, linux-spi, linux-arm-kernel,
	linux-kernel, devicetree, linux-serial
In-Reply-To: <20180525171941.26766-3-radu.pirea@microchip.com>

On Fri, May 25, 2018 at 08:19:37PM +0300, Radu Pirea wrote:
> This patch moves the bindings for serial from serial/atmel-usart.txt to
> mfd/atmel-usart.txt and adds bindings for USART in SPI mode.
> 
> Signed-off-by: Radu Pirea <radu.pirea@microchip.com>
> ---
>  .../bindings/{serial => mfd}/atmel-usart.txt  | 25 +++++++++++++++++--
>  1 file changed, 23 insertions(+), 2 deletions(-)
>  rename Documentation/devicetree/bindings/{serial => mfd}/atmel-usart.txt (76%)

Reviewed-by: Rob Herring <robh@kernel.org>

^ permalink raw reply

* Re: [PATCH RESEND] serdev: add controller runtime PM support
From: Rob Herring @ 2018-05-30 13:20 UTC (permalink / raw)
  To: Johan Hovold
  Cc: Greg Kroah-Hartman, Sebastian Reichel, Tony Lindgren,
	H. Nikolaus Schaller, Andreas Kemnade, Mark Rutland,
	Arnd Bergmann, Pavel Machek, linux-kernel@vger.kernel.org,
	open list:SERIAL DRIVERS, linux-pm
In-Reply-To: <20180530105059.21409-1-johan@kernel.org>

On Wed, May 30, 2018 at 5:50 AM, Johan Hovold <johan@kernel.org> wrote:
> Add support for controller runtime power management to serdev core. This
> is needed to allow slave drivers to manage the runtime PM state of the
> underlying serial controller when its driver, in turn, implements more
> aggressive runtime power management (e.g. using autosuspend).
>
> For some applications, for example, where loss off initial data after a
> remote-wakeup event is acceptable or where rx is not used at all,
> aggressive serial controller runtime PM may be used without further
> involvement of the slave driver. But when this is not the case, the
> slave driver must be able to indicate when incoming data is expected in
> order to avoid data loss.
>
> To facilitate the common case, where the serial controller power state
> is active whenever the port is open (which is the case with just about
> every serial driver), and where data loss is not acceptable and cannot
> even be prevented by explicit controller runtime power management, an
> RPM reference is taken in serdev open and put again at close. This
> reference can later be balanced by any serdev driver which wants and/or
> can handle aggressive controller runtime PM.
>
> Note that the .ignore_children flag is set for the serdev controller to
> allow the underlying hardware to idle when no I/O is expected, regardless
> of the slave device RPM state.
>
> Acked-by: Tony Lindgren <tony@atomide.com>
> Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
> Signed-off-by: Johan Hovold <johan@kernel.org>
> ---
>
> Hi Rob and Greg,
>
> This is a resend of the serdev controller runtime PM patch, which you
> haven't commented on yet (possibly due to the following extensive
> discussions on how to generalise the aggressive OMAP serial runtime PM
> implementation).
>
> This patch works with what we have today, regardless of how we end up
> configuring the serial controller (active) runtime PM behaviour
> (currently done through sysfs for OMAP), which is a separate issue.
>
> No changes in this resend, besides me adding Tony's and Sebastian's ack
> and reviewed-by tags and dropping the second patch which only served as
> an example of how to use this in a serdev driver.

Acked-by: Rob Herring <robh@kernel.org>

Rob

^ permalink raw reply

* [PATCH RESEND] serdev: add controller runtime PM support
From: Johan Hovold @ 2018-05-30 10:50 UTC (permalink / raw)
  To: Greg Kroah-Hartman, Rob Herring
  Cc: Sebastian Reichel, Tony Lindgren, H. Nikolaus Schaller,
	Andreas Kemnade, Mark Rutland, Arnd Bergmann, Pavel Machek,
	linux-kernel, linux-serial, linux-pm, Johan Hovold

Add support for controller runtime power management to serdev core. This
is needed to allow slave drivers to manage the runtime PM state of the
underlying serial controller when its driver, in turn, implements more
aggressive runtime power management (e.g. using autosuspend).

For some applications, for example, where loss off initial data after a
remote-wakeup event is acceptable or where rx is not used at all,
aggressive serial controller runtime PM may be used without further
involvement of the slave driver. But when this is not the case, the
slave driver must be able to indicate when incoming data is expected in
order to avoid data loss.

To facilitate the common case, where the serial controller power state
is active whenever the port is open (which is the case with just about
every serial driver), and where data loss is not acceptable and cannot
even be prevented by explicit controller runtime power management, an
RPM reference is taken in serdev open and put again at close. This
reference can later be balanced by any serdev driver which wants and/or
can handle aggressive controller runtime PM.

Note that the .ignore_children flag is set for the serdev controller to
allow the underlying hardware to idle when no I/O is expected, regardless
of the slave device RPM state.

Acked-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Johan Hovold <johan@kernel.org>
---

Hi Rob and Greg,

This is a resend of the serdev controller runtime PM patch, which you
haven't commented on yet (possibly due to the following extensive
discussions on how to generalise the aggressive OMAP serial runtime PM
implementation).

This patch works with what we have today, regardless of how we end up
configuring the serial controller (active) runtime PM behaviour
(currently done through sysfs for OMAP), which is a separate issue.

No changes in this resend, besides me adding Tony's and Sebastian's ack
and reviewed-by tags and dropping the second patch which only served as
an example of how to use this in a serdev driver.

Johan


 drivers/tty/serdev/core.c | 33 ++++++++++++++++++++++++++++++---
 1 file changed, 30 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
index df93b727e984..e5e84303faca 100644
--- a/drivers/tty/serdev/core.c
+++ b/drivers/tty/serdev/core.c
@@ -13,6 +13,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/serdev.h>
 #include <linux/slab.h>
 
@@ -143,11 +144,28 @@ EXPORT_SYMBOL_GPL(serdev_device_remove);
 int serdev_device_open(struct serdev_device *serdev)
 {
 	struct serdev_controller *ctrl = serdev->ctrl;
+	int ret;
 
 	if (!ctrl || !ctrl->ops->open)
 		return -EINVAL;
 
-	return ctrl->ops->open(ctrl);
+	ret = ctrl->ops->open(ctrl);
+	if (ret)
+		return ret;
+
+	ret = pm_runtime_get_sync(&ctrl->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(&ctrl->dev);
+		goto err_close;
+	}
+
+	return 0;
+
+err_close:
+	if (ctrl->ops->close)
+		ctrl->ops->close(ctrl);
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(serdev_device_open);
 
@@ -158,6 +176,8 @@ void serdev_device_close(struct serdev_device *serdev)
 	if (!ctrl || !ctrl->ops->close)
 		return;
 
+	pm_runtime_put(&ctrl->dev);
+
 	ctrl->ops->close(ctrl);
 }
 EXPORT_SYMBOL_GPL(serdev_device_close);
@@ -416,6 +436,9 @@ struct serdev_controller *serdev_controller_alloc(struct device *parent,
 
 	dev_set_name(&ctrl->dev, "serial%d", id);
 
+	pm_runtime_no_callbacks(&ctrl->dev);
+	pm_suspend_ignore_children(&ctrl->dev, true);
+
 	dev_dbg(&ctrl->dev, "allocated controller 0x%p id %d\n", ctrl, id);
 	return ctrl;
 
@@ -547,20 +570,23 @@ int serdev_controller_add(struct serdev_controller *ctrl)
 	if (ret)
 		return ret;
 
+	pm_runtime_enable(&ctrl->dev);
+
 	ret_of = of_serdev_register_devices(ctrl);
 	ret_acpi = acpi_serdev_register_devices(ctrl);
 	if (ret_of && ret_acpi) {
 		dev_dbg(&ctrl->dev, "no devices registered: of:%d acpi:%d\n",
 			ret_of, ret_acpi);
 		ret = -ENODEV;
-		goto out_dev_del;
+		goto err_rpm_disable;
 	}
 
 	dev_dbg(&ctrl->dev, "serdev%d registered: dev:%p\n",
 		ctrl->nr, &ctrl->dev);
 	return 0;
 
-out_dev_del:
+err_rpm_disable:
+	pm_runtime_disable(&ctrl->dev);
 	device_del(&ctrl->dev);
 	return ret;
 };
@@ -591,6 +617,7 @@ void serdev_controller_remove(struct serdev_controller *ctrl)
 
 	dummy = device_for_each_child(&ctrl->dev, NULL,
 				      serdev_remove_device);
+	pm_runtime_disable(&ctrl->dev);
 	device_del(&ctrl->dev);
 }
 EXPORT_SYMBOL_GPL(serdev_controller_remove);
-- 
2.17.0

^ permalink raw reply related

* Re: [PATCH 07/19] serdev: Allows dynamic creation of devices via sysfs
From: Ricardo Ribalda Delgado @ 2018-05-29 21:23 UTC (permalink / raw)
  To: Andy Shevchenko
  Cc: LKML, open list:SERIAL DRIVERS, Rob Herring, Johan Hovold,
	Greg Kroah-Hartman, Jiri Slaby
In-Reply-To: <CAHp75Ve_=euX83qVfArU+ZbcU2Z_PnBdtQGi7XbA7AVfM1XO-w@mail.gmail.com>

Hi Andy,

On Tue, May 29, 2018 at 10:35 PM Andy Shevchenko <andy.shevchenko@gmail.com>
wrote:

> On Tue, May 29, 2018 at 4:10 PM, Ricardo Ribalda Delgado
> <ricardo.ribalda@gmail.com> wrote:
> > Allow creating and deleting devices via sysfs. Devices created will be
> > matched to serdev drivers via modalias (the string provided by the user)
> > and deleted via their name.

> > +       int err;
> > +       char *nline;

> Better to read in reversed order.

> > +       nline = strchr(buf, '\n');
> > +       if (nline)
> > +               *nline = '\0';

> strim() / strstrip() ?

> > +       nline = strchr(buf, '\n');
> > +       if (nline)
> > +               *nline = '\0';

> Ditto.

> > +static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, 0200, NULL,
> > +                                 delete_device_store);

> Perhaps leave it on one line?

> --
> With Best Regards,
> Andy Shevchenko

Thanks for your review. I am working on v2 at
https://github.com/ribalda/linux/tree/serdev2 it fixes your comments except
the line cut for DEVICE_ATTR, I want also to make checkpatch happy ;)

Will send v2  to the list after I got more feedback, you can of course ping
me if there is something in my tree that it is not fixed properly.

Cheers


-- 
Ricardo Ribalda

^ permalink raw reply

* Re: [patch v25 0/4] JTAG driver introduction
From: Andy Shevchenko @ 2018-05-29 20:40 UTC (permalink / raw)
  To: Oleksandr Shamray
  Cc: Greg Kroah-Hartman, Arnd Bergmann, Linux Kernel Mailing List,
	linux-arm Mailing List, devicetree, openbmc, Joel Stanley,
	Jiří Pírko, Tobias Klauser,
	open list:SERIAL DRIVERS, Vadim Pasternak, system-sw-low-level,
	Rob Herring, openocd-devel-owner, linux-api, David S. Miller,
	Mauro Carvalho Chehab
In-Reply-To: <1527605618-15705-1-git-send-email-oleksandrs@mellanox.com>

On Tue, May 29, 2018 at 5:53 PM, Oleksandr Shamray
<oleksandrs@mellanox.com> wrote:

Please, STOP spamming mailing lists. Give (potential) reviewers time
to look at this.
In any case you already missed a next cycle, so, calm down and better
collect reports and address comments thoroughly.

-- 
With Best Regards,
Andy Shevchenko

^ permalink raw reply

* Re: [PATCH 07/19] serdev: Allows dynamic creation of devices via sysfs
From: Andy Shevchenko @ 2018-05-29 20:35 UTC (permalink / raw)
  To: Ricardo Ribalda Delgado
  Cc: Linux Kernel Mailing List, open list:SERIAL DRIVERS, Rob Herring,
	Johan Hovold, Greg Kroah-Hartman, Jiri Slaby
In-Reply-To: <20180529131014.18641-8-ricardo.ribalda@gmail.com>

On Tue, May 29, 2018 at 4:10 PM, Ricardo Ribalda Delgado
<ricardo.ribalda@gmail.com> wrote:
> Allow creating and deleting devices via sysfs. Devices created will be
> matched to serdev drivers via modalias (the string provided by the user)
> and deleted via their name.

> +       int err;
> +       char *nline;

Better to read in reversed order.

> +       nline = strchr(buf, '\n');
> +       if (nline)
> +               *nline = '\0';

strim() / strstrip() ?

> +       nline = strchr(buf, '\n');
> +       if (nline)
> +               *nline = '\0';

Ditto.

> +static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, 0200, NULL,
> +                                 delete_device_store);

Perhaps leave it on one line?

-- 
With Best Regards,
Andy Shevchenko

^ permalink raw reply

* Re: [patch v22 1/4] drivers: jtag: Add JTAG core driver
From: kbuild test robot @ 2018-05-29 20:08 UTC (permalink / raw)
  Cc: kbuild-all, gregkh, arnd, linux-kernel, linux-arm-kernel,
	devicetree, openbmc, joel, jiri, tklauser, linux-serial, vadimp,
	system-sw-low-level, robh+dt, openocd-devel-owner, linux-api,
	davem, mchehab, Oleksandr Shamray
In-Reply-To: <1527503652-21975-2-git-send-email-oleksandrs@mellanox.com>

[-- Attachment #1: Type: text/plain, Size: 1553 bytes --]

Hi Oleksandr,

I love your patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v4.17-rc7 next-20180529]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Oleksandr-Shamray/JTAG-driver-introduction/20180529-195609
config: sh-allmodconfig (attached as .config)
compiler: sh4-linux-gnu-gcc (Debian 7.2.0-11) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=sh 

All errors (new ones prefixed by >>):

>> drivers/jtag/jtag.c:288:13: error: static declaration of 'devm_jtag_unregister' follows non-static declaration
    static void devm_jtag_unregister(struct device *dev, void *res)
                ^~~~~~~~~~~~~~~~~~~~
   In file included from drivers/jtag/jtag.c:9:0:
   include/linux/jtag.h:38:6: note: previous declaration of 'devm_jtag_unregister' was here
    void devm_jtag_unregister(struct device *dev, void *res);
         ^~~~~~~~~~~~~~~~~~~~

vim +/devm_jtag_unregister +288 drivers/jtag/jtag.c

   287	
 > 288	static void devm_jtag_unregister(struct device *dev, void *res)
   289	{
   290		jtag_unregister(*(struct jtag **)res);
   291	}
   292	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 47739 bytes --]

^ permalink raw reply

* Re: [patch v25 4/4] Documentation: jtag: Add ABI documentation
From: Randy Dunlap @ 2018-05-29 18:54 UTC (permalink / raw)
  To: Oleksandr Shamray, gregkh, arnd
  Cc: system-sw-low-level, devicetree, jiri, vadimp, linux-api, openbmc,
	linux-kernel, openocd-devel-owner, robh+dt, joel, linux-serial,
	tklauser, mchehab, davem, linux-arm-kernel
In-Reply-To: <1527605618-15705-5-git-send-email-oleksandrs@mellanox.com>

On 05/29/2018 07:53 AM, Oleksandr Shamray wrote:
> Added document that describe the ABI for JTAG class drivrer

Sorry, there are still a few typos.  Please see below.

> ---
>  Documentation/ABI/testing/gpio-cdev |    1 -
>  Documentation/ABI/testing/jtag-dev  |   23 +++++++
>  Documentation/jtag/overview         |   27 +++++++++
>  Documentation/jtag/transactions     |  109 +++++++++++++++++++++++++++++++++++
>  MAINTAINERS                         |    1 +
>  5 files changed, 160 insertions(+), 1 deletions(-)
>  create mode 100644 Documentation/ABI/testing/jtag-dev
>  create mode 100644 Documentation/jtag/overview
>  create mode 100644 Documentation/jtag/transactions
> 

> diff --git a/Documentation/jtag/overview b/Documentation/jtag/overview
> new file mode 100644
> index 0000000..f179095
> --- /dev/null
> +++ b/Documentation/jtag/overview
> @@ -0,0 +1,27 @@
> +Linux kernel JTAG support
> +=========================
> +
> +JTAG is an industry standard for verifying hardware.JTAG provides access to

needs space:
                                              hardware. JTAG provides

> +many logic signals of a complex integrated circuit, including the device pins.
> +
> +A JTAG interface is a special interface added to a chip.
> +Depending on the version of JTAG, two, four, or five pins are added.
> +
> +The connector pins are:
> +	TDI (Test Data In)
> +	TDO (Test Data Out)
> +	TCK (Test Clock)
> +	TMS (Test Mode Select)
> +	TRST (Test Reset) optional
> +
> +JTAG interface is designed to have two parts - basic core driver and
> +hardware specific driver. The basic driver introduces a general interface
> +which is not dependent of specific hardware. It provides communication
> +between user space and hardware specific driver.
> +Each JTAG device is represented as a char device from (jtag0, jtag1, ...).
> +Access to a JTAG device is performed through IOCTL calls.
> +
> +Call flow example:
> +User: open  -> /dev/jatgX
> +User: ioctl -> /dev/jtagX -> JTAG core driver -> JTAG hardware specific driver
> +User: close -> /dev/jatgX

> diff --git a/Documentation/jtag/transactions b/Documentation/jtag/transactions
> new file mode 100644
> index 0000000..c5176a7
> --- /dev/null
> +++ b/Documentation/jtag/transactions
> @@ -0,0 +1,109 @@
> +The JTAG API
> +=============
> +
> +JTAG master devices can be accessed through a character misc-device.
> +Each JTAG master interface can be accessed by using /dev/jtagN.
> +
> +JTAG system calls set:
> +- SIR (Scan Instruction Register, IEEE 1149.1 Instruction Register scan);
> +- SDR (Scan Data Register, IEEE 1149.1 Data Register scan);
> +- RUNTEST (Forces the IEEE 1149.1 bus to a run state for a specified
> +number of clocks.
> +
> +open(), close()
> +-------
> +open() opens JTAG device.
> +
> +Open/Close  device:
> +- jtag_fd = open("/dev/jtag0", O_RDWR);
> +- close(jtag_fd);
> +
> +ioctl()
> +-------
> +All access operations to JTAG devices are erformed through ioctl interface.

                                             performed

> +The IOCTL interface supports these requests:
> +	JTAG_IOCRUNTEST - Force JTAG state machine to RUN_TEST/IDLE state
> +	JTAG_SIOCFREQ - Set JTAG TCK frequency
> +	JTAG_GIOCFREQ - Get JTAG TCK frequency
> +	JTAG_IOCXFER - send JTAG data Xfer
> +	JTAG_GIOCSTATUS - get current JTAG TAP status
> +	JTAG_SIOCMODE - set JTAG mode flags.



-- 
~Randy

^ permalink raw reply

* Re: [PATCH 07/19] serdev: Allows dynamic creation of devices via sysfs
From: Ricardo Ribalda Delgado @ 2018-05-29 16:32 UTC (permalink / raw)
  To: Rob Herring
  Cc: LKML, open list:SERIAL DRIVERS, Johan Hovold, Greg Kroah-Hartman,
	Jiri Slaby, Wolfram Sang
In-Reply-To: <CAPybu_1Pxc_Bd9gTaKO2TJ83aZbA4R1wcAhCE+HQxJbfAFNYDA@mail.gmail.com>

Using the right address for Wolfram
On Tue, May 29, 2018 at 6:30 PM Ricardo Ribalda Delgado <
ricardo.ribalda@gmail.com> wrote:

> Hi Rob

> On Tue, May 29, 2018 at 5:38 PM Rob Herring <robh@kernel.org> wrote:

> > On Tue, May 29, 2018 at 8:10 AM, Ricardo Ribalda Delgado
> > <ricardo.ribalda@gmail.com> wrote:
> > > Allow creating and deleting devices via sysfs. Devices created will be
> > > matched to serdev drivers via modalias (the string provided by the
user)
> > > and deleted via their name. Eg:
> > >
> > >  # Create device
> > > root@qt5022:~# echo ttydev >
/sys/bus/serial/devices/serial0/new_device
> > >
> > >  # Delete device
> > > root@qt5022:~#
> > >         echo serial0-0 > /sys/bus/serial/devices/serial0/delete_device

> > I think the model here should be the kernel provides dummy slave
> > device for each serial port and then you can use bind and unbind to
> > bind to a particular driver.


> I have been researching a bit that approach, but I found a couple of
issues:

> - With the bind/unbind you need to modprobe manually the module. Something
> like

> modprobe myserdev
> echo myserdev > bind

> - You need one module per part_number, with modalias you can have a
> different alias per module

> - I guess that the final user will appreciate that the serdev has the same
> API as other serial slow bus (i2c).

> ccing Wolfram becase maybe he has some feedback to same from his
experience
> with the i2c bus.

> Thanks!


> > Rob



> --
> Ricardo Ribalda



-- 
Ricardo Ribalda

^ permalink raw reply

* Re: [PATCH 07/19] serdev: Allows dynamic creation of devices via sysfs
From: Ricardo Ribalda Delgado @ 2018-05-29 16:30 UTC (permalink / raw)
  To: Rob Herring
  Cc: LKML, open list:SERIAL DRIVERS, Johan Hovold, Greg Kroah-Hartman,
	Jiri Slaby, Wolfram Sang
In-Reply-To: <CAL_JsqKRqKJmPc-QQBcN9j5=_y+MH+Rn1aZNun=MAgBMpvDL2w@mail.gmail.com>

Hi Rob

On Tue, May 29, 2018 at 5:38 PM Rob Herring <robh@kernel.org> wrote:

> On Tue, May 29, 2018 at 8:10 AM, Ricardo Ribalda Delgado
> <ricardo.ribalda@gmail.com> wrote:
> > Allow creating and deleting devices via sysfs. Devices created will be
> > matched to serdev drivers via modalias (the string provided by the user)
> > and deleted via their name. Eg:
> >
> >  # Create device
> > root@qt5022:~# echo ttydev > /sys/bus/serial/devices/serial0/new_device
> >
> >  # Delete device
> > root@qt5022:~#
> >         echo serial0-0 > /sys/bus/serial/devices/serial0/delete_device

> I think the model here should be the kernel provides dummy slave
> device for each serial port and then you can use bind and unbind to
> bind to a particular driver.


I have been researching a bit that approach, but I found a couple of issues:

- With the bind/unbind you need to modprobe manually the module. Something
like

modprobe myserdev
echo myserdev > bind

- You need one module per part_number, with modalias you can have a
different alias per module

- I guess that the final user will appreciate that the serdev has the same
API as other serial slow bus (i2c).

ccing Wolfram becase maybe he has some feedback to same from his experience
with the i2c bus.

Thanks!


> Rob



-- 
Ricardo Ribalda

^ permalink raw reply

* Re: [PATCH 07/19] serdev: Allows dynamic creation of devices via sysfs
From: Rob Herring @ 2018-05-29 15:38 UTC (permalink / raw)
  To: Ricardo Ribalda Delgado
  Cc: linux-kernel@vger.kernel.org, open list:SERIAL DRIVERS,
	Johan Hovold, Greg Kroah-Hartman, Jiri Slaby
In-Reply-To: <20180529131014.18641-8-ricardo.ribalda@gmail.com>

On Tue, May 29, 2018 at 8:10 AM, Ricardo Ribalda Delgado
<ricardo.ribalda@gmail.com> wrote:
> Allow creating and deleting devices via sysfs. Devices created will be
> matched to serdev drivers via modalias (the string provided by the user)
> and deleted via their name. Eg:
>
>  # Create device
> root@qt5022:~# echo ttydev > /sys/bus/serial/devices/serial0/new_device
>
>  # Delete device
> root@qt5022:~#
>         echo serial0-0 > /sys/bus/serial/devices/serial0/delete_device

I think the model here should be the kernel provides dummy slave
device for each serial port and then you can use bind and unbind to
bind to a particular driver.

Rob

^ permalink raw reply

* [patch v25 4/4] Documentation: jtag: Add ABI documentation
From: Oleksandr Shamray @ 2018-05-29 14:53 UTC (permalink / raw)
  To: gregkh, arnd
  Cc: linux-kernel, linux-arm-kernel, devicetree, openbmc, joel, jiri,
	tklauser, linux-serial, vadimp, system-sw-low-level, robh+dt,
	openocd-devel-owner, linux-api, davem, mchehab, Oleksandr Shamray
In-Reply-To: <1527605618-15705-1-git-send-email-oleksandrs@mellanox.com>

Added document that describe the ABI for JTAG class drivrer

Signed-off-by: Oleksandr Shamray <oleksandrs@mellanox.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
---
v24->v25
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- Fixed documentation according to new open() behavior

v23->24
v22->v23
Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- fix spell in ABI doccumentation

v21->v22
Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- fix spell in ABI doccumentation

v20->v21
Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- Fix JTAG dirver help in Kconfig

v19->v20
Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- Fix JTAG doccumentation

v18->v19
Pavel Machek <pavel@ucw.cz>
- Added JTAG doccumentation to Documentation/jtag

v17->v18
v16->v17
v15->v16
v14->v15
v13->v14
v12->v13
v11->v12 Tobias Klauser <tklauser@distanz.ch>
Comments pointed by
- rename /Documentation/ABI/testing/jatg-dev -> jtag-dev
- Typo: s/interfase/interface
v10->v11
v9->v10
Fixes added by Oleksandr:
- change jtag-cdev to jtag-dev in documentation
- update KernelVersion and Date in jtag-dev documentation;
v8->v9
v7->v8
v6->v7
Comments pointed by Pavel Machek <pavel@ucw.cz>
- Added jtag-cdev documentation to Documentation/ABI/testing folder
---
 Documentation/ABI/testing/gpio-cdev |    1 -
 Documentation/ABI/testing/jtag-dev  |   23 +++++++
 Documentation/jtag/overview         |   27 +++++++++
 Documentation/jtag/transactions     |  109 +++++++++++++++++++++++++++++++++++
 MAINTAINERS                         |    1 +
 5 files changed, 160 insertions(+), 1 deletions(-)
 create mode 100644 Documentation/ABI/testing/jtag-dev
 create mode 100644 Documentation/jtag/overview
 create mode 100644 Documentation/jtag/transactions

diff --git a/Documentation/ABI/testing/gpio-cdev b/Documentation/ABI/testing/gpio-cdev
index 7b265fb..c09d589 100644
--- a/Documentation/ABI/testing/gpio-cdev
+++ b/Documentation/ABI/testing/gpio-cdev
@@ -12,7 +12,6 @@ Description:
 		The following file operations are supported:
 
 		open(2)
-		Currently the only useful flags are O_RDWR.
 
 		ioctl(2)
 		Initiate various actions.
diff --git a/Documentation/ABI/testing/jtag-dev b/Documentation/ABI/testing/jtag-dev
new file mode 100644
index 0000000..08249fe
--- /dev/null
+++ b/Documentation/ABI/testing/jtag-dev
@@ -0,0 +1,23 @@
+What:		/dev/jtag[0-9]+
+Date:		May 2018
+KernelVersion:	4.18
+Contact:	oleksandrs@mellanox.com
+Description:
+		The misc device files /dev/jtag* are the interface
+		between JTAG master interface and userspace.
+
+		The ioctl(2)-based ABI is defined and documented in
+		[include/uapi]<linux/jtag.h>.
+
+		The following file operations are supported:
+
+		open(2)
+		Opens and allocates file descriptor.
+
+		ioctl(2)
+		Initiate various actions.
+		See the inline documentation in [include/uapi]<linux/jtag.h>
+		for descriptions of all ioctls.
+
+Users:
+		userspace tools which wants to access to JTAG bus
diff --git a/Documentation/jtag/overview b/Documentation/jtag/overview
new file mode 100644
index 0000000..f179095
--- /dev/null
+++ b/Documentation/jtag/overview
@@ -0,0 +1,27 @@
+Linux kernel JTAG support
+=========================
+
+JTAG is an industry standard for verifying hardware.JTAG provides access to
+many logic signals of a complex integrated circuit, including the device pins.
+
+A JTAG interface is a special interface added to a chip.
+Depending on the version of JTAG, two, four, or five pins are added.
+
+The connector pins are:
+	TDI (Test Data In)
+	TDO (Test Data Out)
+	TCK (Test Clock)
+	TMS (Test Mode Select)
+	TRST (Test Reset) optional
+
+JTAG interface is designed to have two parts - basic core driver and
+hardware specific driver. The basic driver introduces a general interface
+which is not dependent of specific hardware. It provides communication
+between user space and hardware specific driver.
+Each JTAG device is represented as a char device from (jtag0, jtag1, ...).
+Access to a JTAG device is performed through IOCTL calls.
+
+Call flow example:
+User: open  -> /dev/jatgX
+User: ioctl -> /dev/jtagX -> JTAG core driver -> JTAG hardware specific driver
+User: close -> /dev/jatgX
diff --git a/Documentation/jtag/transactions b/Documentation/jtag/transactions
new file mode 100644
index 0000000..c5176a7
--- /dev/null
+++ b/Documentation/jtag/transactions
@@ -0,0 +1,109 @@
+The JTAG API
+=============
+
+JTAG master devices can be accessed through a character misc-device.
+Each JTAG master interface can be accessed by using /dev/jtagN.
+
+JTAG system calls set:
+- SIR (Scan Instruction Register, IEEE 1149.1 Instruction Register scan);
+- SDR (Scan Data Register, IEEE 1149.1 Data Register scan);
+- RUNTEST (Forces the IEEE 1149.1 bus to a run state for a specified
+number of clocks.
+
+open(), close()
+-------
+open() opens JTAG device.
+
+Open/Close  device:
+- jtag_fd = open("/dev/jtag0", O_RDWR);
+- close(jtag_fd);
+
+ioctl()
+-------
+All access operations to JTAG devices are erformed through ioctl interface.
+The IOCTL interface supports these requests:
+	JTAG_IOCRUNTEST - Force JTAG state machine to RUN_TEST/IDLE state
+	JTAG_SIOCFREQ - Set JTAG TCK frequency
+	JTAG_GIOCFREQ - Get JTAG TCK frequency
+	JTAG_IOCXFER - send JTAG data Xfer
+	JTAG_GIOCSTATUS - get current JTAG TAP status
+	JTAG_SIOCMODE - set JTAG mode flags.
+
+JTAG_SIOCFREQ, JTAG_GIOCFREQ
+------
+Set/Get JTAG clock speed:
+
+	unsigned int jtag_fd;
+	ioctl(jtag_fd, JTAG_SIOCFREQ, &frq);
+	ioctl(jtag_fd, JTAG_GIOCFREQ, &frq);
+
+JTAG_IOCRUNTEST
+------
+Force JTAG state machine to RUN_TEST/IDLE state
+
+struct jtag_run_test_idle {
+	__u8	reset;
+	__u8	endstate;
+	__u8	tck;
+};
+
+reset:
+	JTAG_NO_RESET - run IDLE/PAUSE from current state
+	JTAG_FORCE_RESET - go through TEST_LOGIC/RESET state before IDLE/PAUSE
+endstate: completion flag
+tck: clock counter
+
+Example:
+	struct jtag_run_test_idle runtest;
+
+	runtest.endstate = JTAG_STATE_IDLE;
+	runtest.reset = 0;
+	runtest.tck = data_p->tck;
+	usleep(25 * 1000);
+	ioctl(jtag_fd, JTAG_IOCRUNTEST, &runtest);
+
+JTAG_IOCXFER
+------
+Send SDR/SIR transaction
+
+struct jtag_xfer {
+	__u8	type;
+	__u8	direction;
+	__u8	endstate;
+	__u8	padding;
+	__u32	length;
+	__u64	tdio;
+};
+
+type: transfer type - JTAG_SIR_XFER/JTAG_SDR_XFER
+direction: xfer direction - JTAG_SIR_XFER/JTAG_SDR_XFER
+length: xfer data length in bits
+tdio : xfer data array
+endstate: xfer end state after transaction finish
+	   can be: JTAG_STATE_IDLE/JTAG_STATE_PAUSEIR/JTAG_STATE_PAUSEDR
+
+Example:
+	struct jtag_xfer xfer;
+	static char buf[64];
+	static unsigned int buf_len = 0;
+	[...]
+	xfer.type = JTAG_SDR_XFER;
+	xfer.tdio = (__u64)buf;
+	xfer.length = buf_len;
+	xfer.endstate = JTAG_STATE_IDLE;
+
+	if (is_read)
+		xfer.direction = JTAG_READ_XFER;
+	else
+		xfer.direction = JTAG_WRITE_XFER;
+
+	ioctl(jtag_fd, JTAG_IOCXFER, &xfer);
+
+JTAG_SIOCMODE
+------
+If hardware driver can support different running modes you can change it.
+
+Example:
+	unsigned int mode;
+	mode = JTAG_XFER_HW_MODE;
+	ioctl(jtag_fd, JTAG_SIOCMODE, &mode);
diff --git a/MAINTAINERS b/MAINTAINERS
index a5e5f75..e067eda 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7618,6 +7618,7 @@ F:	include/linux/jtag.h
 F:	include/uapi/linux/jtag.h
 F:	drivers/jtag/
 F:	Documentation/devicetree/bindings/jtag/
+F:	Documentation/ABI/testing/jtag-dev
 
 K10TEMP HARDWARE MONITORING DRIVER
 M:	Clemens Ladisch <clemens@ladisch.de>
-- 
1.7.1

^ permalink raw reply related

* [patch v25 3/4] Documentation: jtag: Add bindings for Aspeed SoC 24xx and 25xx families JTAG master driver
From: Oleksandr Shamray @ 2018-05-29 14:53 UTC (permalink / raw)
  To: gregkh, arnd
  Cc: linux-kernel, linux-arm-kernel, devicetree, openbmc, joel, jiri,
	tklauser, linux-serial, vadimp, system-sw-low-level, robh+dt,
	openocd-devel-owner, linux-api, davem, mchehab, Oleksandr Shamray
In-Reply-To: <1527605618-15705-1-git-send-email-oleksandrs@mellanox.com>

It has been tested on Mellanox system with BMC equipped with
Aspeed 2520 SoC for programming CPLD devices.

Signed-off-by: Oleksandr Shamray <oleksandrs@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Rob Herring <robh@kernel.org>
---
v21->v22
v20->v21
v19->v20
v18->v19

v17->v18
v16->v17
v15->v16
Comments pointed by Joel Stanley <joel.stan@gmail.com>
- change clocks = <&clk_apb> to proper clocks = <&syscon ASPEED_CLK_APB>
- add reset descriptions in bndings file

v14->v15
v13->v14
v12->v13
v11->v12
v10->v11
v9->v10
v8->v9
v7->v8
Comments pointed by pointed by Joel Stanley <joel.stan@gmail.com>
- Change compatible string to ast2400 and ast2000

V6->v7
Comments pointed by Tobias Klauser <tklauser@distanz.ch>
 - Fix spell "Doccumentation" -> "Documentation"

v5->v6
Comments pointed by Tobias Klauser <tklauser@distanz.ch>
- Small nit: s/documentation/Documentation/

v4->v5

V3->v4
Comments pointed by Rob Herring <robh@kernel.org>
- delete unnecessary "status" and "reg-shift" descriptions in
  bndings file

v2->v3
Comments pointed by Rob Herring <robh@kernel.org>
- split Aspeed jtag driver and binding to sepatrate patches
- delete unnecessary "status" and "reg-shift" descriptions in
  bndings file
---
 .../devicetree/bindings/jtag/aspeed-jtag.txt       |   22 ++++++++++++++++++++
 MAINTAINERS                                        |    1 +
 2 files changed, 23 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/jtag/aspeed-jtag.txt

diff --git a/Documentation/devicetree/bindings/jtag/aspeed-jtag.txt b/Documentation/devicetree/bindings/jtag/aspeed-jtag.txt
new file mode 100644
index 0000000..7c36eb6
--- /dev/null
+++ b/Documentation/devicetree/bindings/jtag/aspeed-jtag.txt
@@ -0,0 +1,22 @@
+Aspeed JTAG driver for ast2400 and ast2500 SoC
+
+Required properties:
+- compatible:		Should be one of
+      - "aspeed,ast2400-jtag"
+      - "aspeed,ast2500-jtag"
+- reg			contains the offset and length of the JTAG memory
+			region
+- clocks		root clock of bus, should reference the APB
+			clock in the second cell
+- resets		phandle to reset controller with the reset number in
+			the second cell
+- interrupts		should contain JTAG controller interrupt
+
+Example:
+jtag: jtag@1e6e4000 {
+	compatible = "aspeed,ast2500-jtag";
+	reg = <0x1e6e4000 0x1c>;
+	clocks = <&syscon ASPEED_CLK_APB>;
+	resets = <&syscon ASPEED_RESET_JTAG_MASTER>;
+	interrupts = <43>;
+};
diff --git a/MAINTAINERS b/MAINTAINERS
index e7b8b2c..a5e5f75 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7617,6 +7617,7 @@ S:	Maintained
 F:	include/linux/jtag.h
 F:	include/uapi/linux/jtag.h
 F:	drivers/jtag/
+F:	Documentation/devicetree/bindings/jtag/
 
 K10TEMP HARDWARE MONITORING DRIVER
 M:	Clemens Ladisch <clemens@ladisch.de>
-- 
1.7.1

^ permalink raw reply related

* [patch v25 2/4] drivers: jtag: Add Aspeed SoC 24xx and 25xx families JTAG master driver
From: Oleksandr Shamray @ 2018-05-29 14:53 UTC (permalink / raw)
  To: gregkh, arnd
  Cc: linux-kernel, linux-arm-kernel, devicetree, openbmc, joel, jiri,
	tklauser, linux-serial, vadimp, system-sw-low-level, robh+dt,
	openocd-devel-owner, linux-api, davem, mchehab, Oleksandr Shamray
In-Reply-To: <1527605618-15705-1-git-send-email-oleksandrs@mellanox.com>

Driver adds support of Aspeed 2500/2400 series SOC JTAG master controller.

Driver implements the following jtag ops:
- freq_get;
- freq_set;
- status_get;
- idle;
- xfer;

It has been tested on Mellanox system with BMC equipped with
Aspeed 2520 SoC for programming CPLD devices.

Signed-off-by: Oleksandr Shamray <oleksandrs@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-by: Joel Stanley <joel@jms.id.au>
---
v24->v25
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- reduced debug printouts

v23->v24
v22->v23
v21->v22
Comments pointed by Andy Shevchenko <andy.shevchenko@gmail.com>
- rearrange ASPEED register defines
- simplified JTAG divider calculation formula
- change delay function in bit-bang operation
- add helper functions for TAP states switching
- remove unnecessary comments
- remove redundant debug messages
- make dines for repetative register bit sets
- fixed indentation
- change checks from negative to positive
- add error check for clk_prepare_enable
- rework driver alloc/register to devm_ variant
- Increasing line length up to 85 in order to improve readability

v20->v21
v19->v20
Notifications from kbuild test robot <lkp@intel.com>
- add static declaration to 'aspeed_jtag_init' and
  'aspeed_jtag_deinit' functions

v18->v19
v17->v18
v16->v17
v15->v16
Comments pointed by Joel Stanley <joel.stan@gmail.com>
- Add reset_control on Jtag init/deinit

v14->v15
Comments pointed by Joel Stanley <joel.stan@gmail.com>
- Add ARCH_ASPEED || COMPILE_TEST to Kconfig
- remove unused offset variable
- remove "aspeed_jtag" from dev_err and dev_dbg messages
- change clk_prepare_enable initialisation order

v13->v14
Comments pointed by Philippe Ombredanne <pombredanne@nexb.com>
- Change style of head block comment from /**/ to //

v12->v13
Comments pointed by Philippe Ombredanne <pombredanne@nexb.com>
- Change jtag-aspeed.c licence type to
  SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note
  and reorder line with license- add reset descriptions in bndings file
 in description
Comments pointed by Kun Yi <kunyi@google.com>
- Changed capability check for aspeed,ast2400-jtag/ast200-jtag

v11->v12
Comments pointed by Chip Bilbrey <chip@bilbrey.org>
- Remove access mode from xfer and idle transactions
- Add new ioctl JTAG_SIOCMODE for set hw mode

v10->v11
v9->v10
V8->v9
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- add *data parameter to xfer function prototype

v7->v8
Comments pointed by Joel Stanley <joel.stan@gmail.com>
- aspeed_jtag_init replace goto to return;
- change input variables type from __u32 to u32
  in functios freq_get, freq_set, status_get
- change sm_ variables type from char to u8
- in jatg_init add disable clocks on error case
- remove release_mem_region on error case
- remove devm_free_irq on jtag_deinit
- Fix misspelling Disabe/Disable
- Change compatible string to ast2400 and ast2000

v6->v7
Notifications from kbuild test robot <lkp@intel.com>
- Add include <linux/types.h> to jtag-asapeed.c

v5->v6
v4->v5
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- Added HAS_IOMEM dependence in Kconfig to avoid
  "undefined reference to `devm_ioremap_resource'" error,
  because in some arch this not supported

v3->v4
Comments pointed by Arnd Bergmann <arnd@arndb.de>
- change transaction pointer tdio type  to __u64
- change internal status type from enum to __u32

v2->v3

v1->v2
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- change license type from GPLv2/BSD to GPLv2

Comments pointed by Neil Armstrong <narmstrong@baylibre.com>
- Add clk_prepare_enable/clk_disable_unprepare in clock init/deinit
- Change .compatible to soc-specific compatible names
  aspeed,aspeed4000-jtag/aspeed5000-jtag
- Added dt-bindings

Comments pointed by Arnd Bergmann <arnd@arndb.de>
- Reorder functions and removed the forward declarations
- Add static const qualifier to state machine states transitions
- Change .compatible to soc-specific compatible names
  aspeed,aspeed4000-jtag/aspeed5000-jtag
- Add dt-bindings

Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- Change module name jtag-aspeed in description in Kconfig

Comments pointed by kbuild test robot <lkp@intel.com>
- Remove invalid include <asm/mach-types.h>
- add resource_size instead of calculation
---
 drivers/jtag/Kconfig       |   14 +
 drivers/jtag/Makefile      |    1 +
 drivers/jtag/jtag-aspeed.c |  756 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 771 insertions(+), 0 deletions(-)
 create mode 100644 drivers/jtag/jtag-aspeed.c

diff --git a/drivers/jtag/Kconfig b/drivers/jtag/Kconfig
index 47771fc..0cc163f 100644
--- a/drivers/jtag/Kconfig
+++ b/drivers/jtag/Kconfig
@@ -15,3 +15,17 @@ menuconfig JTAG
 
 	  To compile this driver as a module, choose M here: the module will
 	  be called jtag.
+
+menuconfig JTAG_ASPEED
+	tristate "Aspeed SoC JTAG controller support"
+	depends on JTAG && HAS_IOMEM
+	depends on ARCH_ASPEED || COMPILE_TEST
+	help
+	  This provides a support for Aspeed JTAG device, equipped on
+	  Aspeed SoC 24xx and 25xx families. Drivers allows programming
+	  of hardware devices, connected to SoC through the JTAG interface.
+
+	  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-aspeed.
diff --git a/drivers/jtag/Makefile b/drivers/jtag/Makefile
index af37493..04a855e 100644
--- a/drivers/jtag/Makefile
+++ b/drivers/jtag/Makefile
@@ -1 +1,2 @@
 obj-$(CONFIG_JTAG)		+= jtag.o
+obj-$(CONFIG_JTAG_ASPEED)	+= jtag-aspeed.o
diff --git a/drivers/jtag/jtag-aspeed.c b/drivers/jtag/jtag-aspeed.c
new file mode 100644
index 0000000..15ae188
--- /dev/null
+++ b/drivers/jtag/jtag-aspeed.c
@@ -0,0 +1,756 @@
+// SPDX-License-Identifier: GPL-2.0
+// drivers/jtag/aspeed-jtag.c
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@mellanox.com>
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/jtag.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <uapi/linux/jtag.h>
+
+#define ASPEED_JTAG_DATA		0x00
+#define ASPEED_JTAG_INST		0x04
+#define ASPEED_JTAG_CTRL		0x08
+#define ASPEED_JTAG_ISR			0x0C
+#define ASPEED_JTAG_SW			0x10
+#define ASPEED_JTAG_TCK			0x14
+#define ASPEED_JTAG_EC			0x18
+
+#define ASPEED_JTAG_DATA_MSB		0x01
+#define ASPEED_JTAG_DATA_CHUNK_SIZE	0x20
+
+/* ASPEED_JTAG_CTRL: Engine Control */
+#define ASPEED_JTAG_CTL_ENG_EN		BIT(31)
+#define ASPEED_JTAG_CTL_ENG_OUT_EN	BIT(30)
+#define ASPEED_JTAG_CTL_FORCE_TMS	BIT(29)
+#define ASPEED_JTAG_CTL_INST_LEN(x)	((x) << 20)
+#define ASPEED_JTAG_CTL_LASPEED_INST	BIT(17)
+#define ASPEED_JTAG_CTL_INST_EN		BIT(16)
+#define ASPEED_JTAG_CTL_DR_UPDATE	BIT(10)
+#define ASPEED_JTAG_CTL_DATA_LEN(x)	((x) << 4)
+#define ASPEED_JTAG_CTL_LASPEED_DATA	BIT(1)
+#define ASPEED_JTAG_CTL_DATA_EN		BIT(0)
+
+/* ASPEED_JTAG_ISR : Interrupt status and enable */
+#define ASPEED_JTAG_ISR_INST_PAUSE	BIT(19)
+#define ASPEED_JTAG_ISR_INST_COMPLETE	BIT(18)
+#define ASPEED_JTAG_ISR_DATA_PAUSE	BIT(17)
+#define ASPEED_JTAG_ISR_DATA_COMPLETE	BIT(16)
+#define ASPEED_JTAG_ISR_INST_PAUSE_EN	BIT(3)
+#define ASPEED_JTAG_ISR_INST_COMPLETE_EN BIT(2)
+#define ASPEED_JTAG_ISR_DATA_PAUSE_EN	BIT(1)
+#define ASPEED_JTAG_ISR_DATA_COMPLETE_EN BIT(0)
+#define ASPEED_JTAG_ISR_INT_EN_MASK	GENMASK(3, 0)
+#define ASPEED_JTAG_ISR_INT_MASK	GENMASK(19, 16)
+
+/* ASPEED_JTAG_SW : Software Mode and Status */
+#define ASPEED_JTAG_SW_MODE_EN		BIT(19)
+#define ASPEED_JTAG_SW_MODE_TCK		BIT(18)
+#define ASPEED_JTAG_SW_MODE_TMS		BIT(17)
+#define ASPEED_JTAG_SW_MODE_TDIO	BIT(16)
+
+/* ASPEED_JTAG_TCK : TCK Control */
+#define ASPEED_JTAG_TCK_DIVISOR_MASK	GENMASK(10, 0)
+#define ASPEED_JTAG_TCK_GET_DIV(x)	((x) & ASPEED_JTAG_TCK_DIVISOR_MASK)
+
+/* ASPEED_JTAG_EC : Controller set for go to IDLE */
+#define ASPEED_JTAG_EC_GO_IDLE		BIT(0)
+
+#define ASPEED_JTAG_IOUT_LEN(len) \
+	(ASPEED_JTAG_CTL_ENG_EN | \
+	 ASPEED_JTAG_CTL_ENG_OUT_EN | \
+	 ASPEED_JTAG_CTL_INST_LEN(len))
+
+#define ASPEED_JTAG_DOUT_LEN(len) \
+	(ASPEED_JTAG_CTL_ENG_EN | \
+	 ASPEED_JTAG_CTL_ENG_OUT_EN | \
+	 ASPEED_JTAG_CTL_DATA_LEN(len))
+
+#define ASPEED_JTAG_SW_TDIO (ASPEED_JTAG_SW_MODE_EN | ASPEED_JTAG_SW_MODE_TDIO)
+
+#define ASPEED_JTAG_GET_TDI(direction, byte) \
+	((direction == JTAG_READ_XFER) ? UINT_MAX : byte)
+
+#define ASPEED_JTAG_TCK_WAIT		10
+#define ASPEED_JTAG_RESET_CNTR		10
+
+#define ASPEED_JTAG_NAME		"jtag-aspeed"
+
+struct aspeed_jtag {
+	void __iomem			*reg_base;
+	struct device			*dev;
+	struct clk			*pclk;
+	enum jtag_endstate		status;
+	int				irq;
+	struct reset_control		*rst;
+	u32				flag;
+	wait_queue_head_t		jtag_wq;
+	u32				mode;
+};
+
+static char *end_status_str[] = {"idle", "ir pause", "drpause"};
+
+static u32 aspeed_jtag_read(struct aspeed_jtag *aspeed_jtag, u32 reg)
+{
+	return readl(aspeed_jtag->reg_base + reg);
+}
+
+static void
+aspeed_jtag_write(struct aspeed_jtag *aspeed_jtag, u32 val, u32 reg)
+{
+	writel(val, aspeed_jtag->reg_base + reg);
+}
+
+static int aspeed_jtag_freq_set(struct jtag *jtag, u32 freq)
+{
+	struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+	unsigned long apb_frq;
+	u32 tck_val;
+	u16 div;
+
+	apb_frq = clk_get_rate(aspeed_jtag->pclk);
+	if (!apb_frq)
+		return -ENOTSUPP;
+
+	div = (apb_frq - 1) / freq;
+	tck_val = aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_TCK);
+	aspeed_jtag_write(aspeed_jtag,
+			  (tck_val & ASPEED_JTAG_TCK_DIVISOR_MASK) | div,
+			  ASPEED_JTAG_TCK);
+	return 0;
+}
+
+static int aspeed_jtag_freq_get(struct jtag *jtag, u32 *frq)
+{
+	struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+	u32 pclk;
+	u32 tck;
+
+	pclk = clk_get_rate(aspeed_jtag->pclk);
+	tck = aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_TCK);
+	*frq = pclk / (ASPEED_JTAG_TCK_GET_DIV(tck) + 1);
+
+	return 0;
+}
+
+static int aspeed_jtag_mode_set(struct jtag *jtag, u32 mode)
+{
+	struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+
+	aspeed_jtag->mode = mode;
+	return 0;
+}
+
+static void aspeed_jtag_sw_delay(struct aspeed_jtag *aspeed_jtag, int cnt)
+{
+	int i;
+
+	for (i = 0; i < cnt; i++)
+		aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_SW);
+}
+
+static char aspeed_jtag_tck_cycle(struct aspeed_jtag *aspeed_jtag,
+				  u8 tms, u8 tdi)
+{
+	char tdo = 0;
+
+	/* TCK = 0 */
+	aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
+			  (tms * ASPEED_JTAG_SW_MODE_TMS) |
+			  (tdi * ASPEED_JTAG_SW_MODE_TDIO), ASPEED_JTAG_SW);
+
+	ndelay(ASPEED_JTAG_TCK_WAIT);
+	aspeed_jtag_sw_delay(aspeed_jtag, ASPEED_JTAG_TCK_WAIT);
+
+	/* TCK = 1 */
+	aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
+			  ASPEED_JTAG_SW_MODE_TCK |
+			  (tms * ASPEED_JTAG_SW_MODE_TMS) |
+			  (tdi * ASPEED_JTAG_SW_MODE_TDIO), ASPEED_JTAG_SW);
+
+	if (aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_SW) &
+	    ASPEED_JTAG_SW_MODE_TDIO)
+		tdo = 1;
+
+	aspeed_jtag_sw_delay(aspeed_jtag, ASPEED_JTAG_TCK_WAIT);
+
+	/* TCK = 0 */
+	aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
+			  (tms * ASPEED_JTAG_SW_MODE_TMS) |
+			  (tdi * ASPEED_JTAG_SW_MODE_TDIO), ASPEED_JTAG_SW);
+	return tdo;
+}
+
+static void aspeed_jtag_wait_instruction_pause(struct aspeed_jtag *aspeed_jtag)
+{
+	wait_event_interruptible(aspeed_jtag->jtag_wq,
+				 aspeed_jtag->flag &  ASPEED_JTAG_ISR_INST_PAUSE);
+	aspeed_jtag->flag &= ~ASPEED_JTAG_ISR_INST_PAUSE;
+}
+
+static void
+aspeed_jtag_wait_instruction_complete(struct aspeed_jtag *aspeed_jtag)
+{
+	wait_event_interruptible(aspeed_jtag->jtag_wq,
+				 aspeed_jtag->flag & ASPEED_JTAG_ISR_INST_COMPLETE);
+	aspeed_jtag->flag &= ~ASPEED_JTAG_ISR_INST_COMPLETE;
+}
+
+static void
+aspeed_jtag_wait_data_pause_complete(struct aspeed_jtag *aspeed_jtag)
+{
+	wait_event_interruptible(aspeed_jtag->jtag_wq,
+				 aspeed_jtag->flag & ASPEED_JTAG_ISR_DATA_PAUSE);
+	aspeed_jtag->flag &= ~ASPEED_JTAG_ISR_DATA_PAUSE;
+}
+
+static void aspeed_jtag_wait_data_complete(struct aspeed_jtag *aspeed_jtag)
+{
+	wait_event_interruptible(aspeed_jtag->jtag_wq,
+				 aspeed_jtag->flag & ASPEED_JTAG_ISR_DATA_COMPLETE);
+	aspeed_jtag->flag &= ~ASPEED_JTAG_ISR_DATA_COMPLETE;
+}
+
+static void aspeed_jtag_sm_cycle(struct aspeed_jtag *aspeed_jtag,
+				 const u8 *tms, int len)
+{
+	int i;
+
+	for (i = 0; i < len; i++)
+		aspeed_jtag_tck_cycle(aspeed_jtag, tms[i], 0);
+}
+
+static void aspeed_jtag_run_idle(struct aspeed_jtag *aspeed_jtag,
+				 struct jtag_run_test_idle *runtest)
+{
+	static const u8 sm_idle_irpause[] = {1, 1, 0, 1, 0};
+	static const u8 sm_idle_drpause[] = {1, 0, 1, 0};
+
+	switch (runtest->endstate) {
+	case JTAG_STATE_PAUSEIR:
+		/* ->DRSCan->IRSCan->IRCap->IRExit1->PauseIR */
+		aspeed_jtag_sm_cycle(aspeed_jtag, sm_idle_irpause,
+				     sizeof(sm_idle_irpause));
+		aspeed_jtag->status = JTAG_STATE_PAUSEIR;
+		break;
+	case JTAG_STATE_PAUSEDR:
+		/* ->DRSCan->DRCap->DRExit1->PauseDR */
+		aspeed_jtag_sm_cycle(aspeed_jtag, sm_idle_drpause,
+				     sizeof(sm_idle_drpause));
+
+		aspeed_jtag->status = JTAG_STATE_PAUSEDR;
+		break;
+	case JTAG_STATE_IDLE:
+		/* IDLE */
+		aspeed_jtag_tck_cycle(aspeed_jtag, 0, 0);
+		aspeed_jtag->status = JTAG_STATE_IDLE;
+		break;
+	default:
+		break;
+	}
+}
+
+static void aspeed_jtag_run_pause(struct aspeed_jtag *aspeed_jtag,
+				  struct jtag_run_test_idle *runtest)
+{
+	static const u8 sm_pause_irpause[] = {1, 1, 1, 1, 0, 1, 0};
+	static const u8 sm_pause_drpause[] = {1, 1, 1, 0, 1, 0};
+	static const u8 sm_pause_idle[] = {1, 1, 0};
+
+	/* From IR/DR Pa.use */
+	switch (runtest->endstate) {
+	case JTAG_STATE_PAUSEIR:
+		/*
+		 * to Exit2 IR/DR->Updt IR/DR->DRSCan->IRSCan->IRCap->
+		 * IRExit1->PauseIR
+		 */
+		aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_irpause,
+				     sizeof(sm_pause_irpause));
+
+		aspeed_jtag->status = JTAG_STATE_PAUSEIR;
+		break;
+	case JTAG_STATE_PAUSEDR:
+		/*
+		 * to Exit2 IR/DR->Updt IR/DR->DRSCan->DRCap->
+		 * DRExit1->PauseDR
+		 */
+		aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_drpause,
+				     sizeof(sm_pause_drpause));
+		aspeed_jtag->status = JTAG_STATE_PAUSEDR;
+		break;
+	case JTAG_STATE_IDLE:
+		/* to Exit2 IR/DR->Updt IR/DR->IDLE */
+		aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_idle,
+				     sizeof(sm_pause_idle));
+		aspeed_jtag->status = JTAG_STATE_IDLE;
+		break;
+	default:
+		break;
+	}
+}
+
+static void aspeed_jtag_run_test_idle_sw(struct aspeed_jtag *aspeed_jtag,
+					 struct jtag_run_test_idle *runtest)
+{
+	int i;
+
+	/* SW mode from idle/pause-> to pause/idle */
+	if (runtest->reset) {
+		for (i = 0; i < ASPEED_JTAG_RESET_CNTR; i++)
+			aspeed_jtag_tck_cycle(aspeed_jtag, 1, 0);
+	}
+
+	switch (aspeed_jtag->status) {
+	case JTAG_STATE_IDLE:
+		aspeed_jtag_run_idle(aspeed_jtag, runtest);
+		break;
+
+	case JTAG_STATE_PAUSEIR:
+	/* Fall-through */
+	case JTAG_STATE_PAUSEDR:
+		aspeed_jtag_run_pause(aspeed_jtag, runtest);
+		break;
+
+	default:
+		dev_err(aspeed_jtag->dev, "aspeed_jtag_run_test_idle error\n");
+		break;
+	}
+
+	/* Stay on IDLE for at least  TCK cycle */
+	for (i = 0; i < runtest->tck; i++)
+		aspeed_jtag_tck_cycle(aspeed_jtag, 0, 0);
+}
+
+static int aspeed_jtag_idle(struct jtag *jtag,
+			    struct jtag_run_test_idle *runtest)
+{
+	struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+
+	dev_dbg(aspeed_jtag->dev, "runtest, state:%s\n",
+		end_status_str[runtest->endstate]);
+
+	if (!(aspeed_jtag->mode & JTAG_XFER_HW_MODE)) {
+		aspeed_jtag_run_test_idle_sw(aspeed_jtag, runtest);
+		return 0;
+	}
+
+	/* Disable sw mode */
+	aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_SW);
+	/* x TMS high + 1 TMS low */
+	if (runtest->reset)
+		aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_CTL_ENG_EN |
+				  ASPEED_JTAG_CTL_ENG_OUT_EN |
+				  ASPEED_JTAG_CTL_FORCE_TMS, ASPEED_JTAG_CTRL);
+	else
+		aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_EC_GO_IDLE,
+				  ASPEED_JTAG_EC);
+
+	aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_TDIO, ASPEED_JTAG_SW);
+
+	aspeed_jtag->status = JTAG_STATE_IDLE;
+	return 0;
+}
+
+static void aspeed_jtag_xfer_sw(struct aspeed_jtag *aspeed_jtag,
+				struct jtag_xfer *xfer, u32 *data)
+{
+	static const u8 sm_update_shiftir[] = { 1, 1, 0, 0 };
+	static const u8 sm_update_shiftdr[] = { 1, 0, 0 };
+	static const u8 sm_pause_idle[] = { 1, 1, 0 };
+	static const u8 sm_pause_update[] = { 1, 1 };
+	unsigned long remain_xfer = xfer->length;
+	unsigned long shift_bits = 0;
+	unsigned long index = 0;
+	unsigned long tdi;
+	char tdo;
+
+	if (aspeed_jtag->status != JTAG_STATE_IDLE) {
+		/*IR/DR Pause->Exit2 IR / DR->Update IR /DR */
+		aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_update,
+				     sizeof(sm_pause_update));
+	}
+
+	if (xfer->type == JTAG_SIR_XFER)
+		/* ->IRSCan->CapIR->ShiftIR */
+		aspeed_jtag_sm_cycle(aspeed_jtag, sm_update_shiftir,
+				     sizeof(sm_update_shiftir));
+	else
+		/* ->DRScan->DRCap->DRShift */
+		aspeed_jtag_sm_cycle(aspeed_jtag, sm_update_shiftdr,
+				     sizeof(sm_update_shiftdr));
+
+	tdi = ASPEED_JTAG_GET_TDI(xfer->direction, data[index]);
+
+	while (remain_xfer > 1) {
+		tdo = aspeed_jtag_tck_cycle(aspeed_jtag, 0,
+					    tdi & ASPEED_JTAG_DATA_MSB);
+		data[index] |= tdo << (shift_bits %
+					    ASPEED_JTAG_DATA_CHUNK_SIZE);
+
+		tdi >>= 1;
+		shift_bits++;
+		remain_xfer--;
+
+		if (shift_bits % ASPEED_JTAG_DATA_CHUNK_SIZE == 0) {
+			tdo = 0;
+			index++;
+
+			tdi = ASPEED_JTAG_GET_TDI(xfer->direction, data[index]);
+		}
+	}
+
+	tdo = aspeed_jtag_tck_cycle(aspeed_jtag, 1, tdi & ASPEED_JTAG_DATA_MSB);
+	data[index] |= tdo << (shift_bits % ASPEED_JTAG_DATA_CHUNK_SIZE);
+
+	/* DIPause/DRPause */
+	aspeed_jtag_tck_cycle(aspeed_jtag, 0, 0);
+
+	if (xfer->endstate == JTAG_STATE_IDLE) {
+		/* ->DRExit2->DRUpdate->IDLE */
+		aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_idle,
+				     sizeof(sm_pause_idle));
+	}
+}
+
+static void aspeed_jtag_xfer_push_data(struct aspeed_jtag *aspeed_jtag,
+				       enum jtag_xfer_type type, u32 bits_len)
+{
+	if (type == JTAG_SIR_XFER) {
+		aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_IOUT_LEN(bits_len),
+				  ASPEED_JTAG_CTRL);
+		aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_DOUT_LEN(bits_len) |
+				  ASPEED_JTAG_CTL_INST_EN, ASPEED_JTAG_CTRL);
+	} else {
+		aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_DOUT_LEN(bits_len),
+				  ASPEED_JTAG_CTRL);
+		aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_DOUT_LEN(bits_len) |
+				  ASPEED_JTAG_CTL_DATA_EN, ASPEED_JTAG_CTRL);
+	}
+}
+
+static void aspeed_jtag_xfer_push_data_last(struct aspeed_jtag *aspeed_jtag,
+					    enum jtag_xfer_type type,
+					    u32 shift_bits,
+					    enum jtag_endstate endstate)
+{
+	if (endstate == JTAG_STATE_IDLE) {
+		if (type == JTAG_SIR_XFER) {
+			aspeed_jtag_write(aspeed_jtag,
+					  ASPEED_JTAG_IOUT_LEN(shift_bits),
+					  ASPEED_JTAG_CTRL);
+			aspeed_jtag_write(aspeed_jtag,
+					  ASPEED_JTAG_IOUT_LEN(shift_bits) |
+					  ASPEED_JTAG_CTL_INST_EN,
+					  ASPEED_JTAG_CTRL);
+			aspeed_jtag_wait_instruction_pause(aspeed_jtag);
+		} else {
+			aspeed_jtag_write(aspeed_jtag,
+					  ASPEED_JTAG_DOUT_LEN(shift_bits) |
+					  ASPEED_JTAG_CTL_DR_UPDATE,
+					  ASPEED_JTAG_CTRL);
+			aspeed_jtag_write(aspeed_jtag,
+					  ASPEED_JTAG_DOUT_LEN(shift_bits) |
+					  ASPEED_JTAG_CTL_DR_UPDATE |
+					  ASPEED_JTAG_CTL_DATA_EN,
+					  ASPEED_JTAG_CTRL);
+			aspeed_jtag_wait_data_pause_complete(aspeed_jtag);
+		}
+	} else {
+		if (type == JTAG_SIR_XFER) {
+			aspeed_jtag_write(aspeed_jtag,
+					  ASPEED_JTAG_IOUT_LEN(shift_bits) |
+					  ASPEED_JTAG_CTL_LASPEED_INST,
+					  ASPEED_JTAG_CTRL);
+			aspeed_jtag_write(aspeed_jtag,
+					  ASPEED_JTAG_IOUT_LEN(shift_bits) |
+					  ASPEED_JTAG_CTL_LASPEED_INST |
+					  ASPEED_JTAG_CTL_INST_EN,
+					  ASPEED_JTAG_CTRL);
+			aspeed_jtag_wait_instruction_complete(aspeed_jtag);
+		} else {
+			aspeed_jtag_write(aspeed_jtag,
+					  ASPEED_JTAG_DOUT_LEN(shift_bits) |
+					  ASPEED_JTAG_CTL_LASPEED_DATA,
+					  ASPEED_JTAG_CTRL);
+			aspeed_jtag_write(aspeed_jtag,
+					  ASPEED_JTAG_DOUT_LEN(shift_bits) |
+					  ASPEED_JTAG_CTL_LASPEED_DATA |
+					  ASPEED_JTAG_CTL_DATA_EN,
+					  ASPEED_JTAG_CTRL);
+			aspeed_jtag_wait_data_complete(aspeed_jtag);
+		}
+	}
+}
+
+static void aspeed_jtag_xfer_hw(struct aspeed_jtag *aspeed_jtag,
+				struct jtag_xfer *xfer, u32 *data)
+{
+	unsigned long remain_xfer = xfer->length;
+	unsigned long index = 0;
+	char shift_bits;
+	u32 data_reg;
+
+	data_reg = xfer->type == JTAG_SIR_XFER ?
+		   ASPEED_JTAG_INST : ASPEED_JTAG_DATA;
+	while (remain_xfer) {
+		if (xfer->direction == JTAG_WRITE_XFER)
+			aspeed_jtag_write(aspeed_jtag, data[index], data_reg);
+		else
+			aspeed_jtag_write(aspeed_jtag, 0, data_reg);
+
+		if (remain_xfer > ASPEED_JTAG_DATA_CHUNK_SIZE) {
+			shift_bits = ASPEED_JTAG_DATA_CHUNK_SIZE;
+
+			/*
+			 * Read bytes were not equals to column length
+			 * and go to Pause-DR
+			 */
+			aspeed_jtag_xfer_push_data(aspeed_jtag, xfer->type,
+						   shift_bits);
+		} else {
+			/*
+			 * Read bytes equals to column length =>
+			 * Update-DR
+			 */
+			shift_bits = remain_xfer;
+			aspeed_jtag_xfer_push_data_last(aspeed_jtag, xfer->type,
+							shift_bits,
+							xfer->endstate);
+		}
+
+		if (xfer->direction == JTAG_READ_XFER) {
+			if (shift_bits < ASPEED_JTAG_DATA_CHUNK_SIZE) {
+				data[index] = aspeed_jtag_read(aspeed_jtag,
+							       data_reg);
+
+				data[index] >>= ASPEED_JTAG_DATA_CHUNK_SIZE -
+								shift_bits;
+			} else {
+				data[index] = aspeed_jtag_read(aspeed_jtag,
+							       data_reg);
+			}
+		}
+
+		remain_xfer = remain_xfer - shift_bits;
+		index++;
+	}
+}
+
+static int aspeed_jtag_xfer(struct jtag *jtag, struct jtag_xfer *xfer,
+			    u8 *xfer_data)
+{
+	struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+
+	dev_dbg(aspeed_jtag->dev, "xfer %s\n",
+		xfer->type == JTAG_SIR_XFER ? "SIR" : "SDR");
+
+	if (!(aspeed_jtag->mode & JTAG_XFER_HW_MODE)) {
+		/* SW mode */
+		aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_TDIO, ASPEED_JTAG_SW);
+
+		aspeed_jtag_xfer_sw(aspeed_jtag, xfer, (u32 *)xfer_data);
+	} else {
+		/* HW mode */
+		aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_SW);
+		aspeed_jtag_xfer_hw(aspeed_jtag, xfer, (u32 *)xfer_data);
+	}
+
+	aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_TDIO, ASPEED_JTAG_SW);
+	aspeed_jtag->status = xfer->endstate;
+	return 0;
+}
+
+static int aspeed_jtag_status_get(struct jtag *jtag, u32 *status)
+{
+	struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+
+	*status = aspeed_jtag->status;
+	return 0;
+}
+
+static irqreturn_t aspeed_jtag_interrupt(s32 this_irq, void *dev_id)
+{
+	struct aspeed_jtag *aspeed_jtag = dev_id;
+	irqreturn_t ret;
+	u32 status;
+
+	status = aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_ISR);
+
+	if (status & ASPEED_JTAG_ISR_INT_MASK) {
+		aspeed_jtag_write(aspeed_jtag,
+				  (status & ASPEED_JTAG_ISR_INT_MASK)
+				  | (status & ASPEED_JTAG_ISR_INT_EN_MASK),
+				  ASPEED_JTAG_ISR);
+		aspeed_jtag->flag |= status & ASPEED_JTAG_ISR_INT_MASK;
+	}
+
+	if (aspeed_jtag->flag) {
+		wake_up_interruptible(&aspeed_jtag->jtag_wq);
+		ret = IRQ_HANDLED;
+	} else {
+		dev_err(aspeed_jtag->dev, "irq status:%x\n",
+			status);
+		ret = IRQ_NONE;
+	}
+	return ret;
+}
+
+static int aspeed_jtag_init(struct platform_device *pdev,
+			    struct aspeed_jtag *aspeed_jtag)
+{
+	struct resource *res;
+	int err;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	aspeed_jtag->reg_base = devm_ioremap_resource(aspeed_jtag->dev, res);
+	if (IS_ERR(aspeed_jtag->reg_base))
+		return -ENOMEM;
+
+	aspeed_jtag->pclk = devm_clk_get(aspeed_jtag->dev, NULL);
+	if (IS_ERR(aspeed_jtag->pclk)) {
+		dev_err(aspeed_jtag->dev, "devm_clk_get failed\n");
+		return PTR_ERR(aspeed_jtag->pclk);
+	}
+
+	aspeed_jtag->irq = platform_get_irq(pdev, 0);
+	if (aspeed_jtag->irq < 0) {
+		dev_err(aspeed_jtag->dev, "no irq specified\n");
+		return -ENOENT;
+	}
+
+	if (clk_prepare_enable(aspeed_jtag->pclk)) {
+		dev_err(aspeed_jtag->dev, "no irq specified\n");
+		return -ENOENT;
+	}
+
+	aspeed_jtag->rst = devm_reset_control_get_shared(&pdev->dev, NULL);
+	if (IS_ERR(aspeed_jtag->rst)) {
+		dev_err(aspeed_jtag->dev,
+			"missing or invalid reset controller device tree entry");
+		return PTR_ERR(aspeed_jtag->rst);
+	}
+	reset_control_deassert(aspeed_jtag->rst);
+
+	/* Enable clock */
+	aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_CTL_ENG_EN |
+			  ASPEED_JTAG_CTL_ENG_OUT_EN, ASPEED_JTAG_CTRL);
+	aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_TDIO, ASPEED_JTAG_SW);
+
+	err = devm_request_irq(aspeed_jtag->dev, aspeed_jtag->irq,
+			       aspeed_jtag_interrupt, 0,
+			       "aspeed-jtag", aspeed_jtag);
+	if (err) {
+		dev_err(aspeed_jtag->dev, "unable to get IRQ");
+		goto clk_unprep;
+	}
+
+	aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_ISR_INST_PAUSE |
+			  ASPEED_JTAG_ISR_INST_COMPLETE |
+			  ASPEED_JTAG_ISR_DATA_PAUSE |
+			  ASPEED_JTAG_ISR_DATA_COMPLETE |
+			  ASPEED_JTAG_ISR_INST_PAUSE_EN |
+			  ASPEED_JTAG_ISR_INST_COMPLETE_EN |
+			  ASPEED_JTAG_ISR_DATA_PAUSE_EN |
+			  ASPEED_JTAG_ISR_DATA_COMPLETE_EN,
+			  ASPEED_JTAG_ISR);
+
+	aspeed_jtag->flag = 0;
+	aspeed_jtag->mode = 0;
+	init_waitqueue_head(&aspeed_jtag->jtag_wq);
+	return 0;
+
+clk_unprep:
+	clk_disable_unprepare(aspeed_jtag->pclk);
+	return err;
+}
+
+static int aspeed_jtag_deinit(struct platform_device *pdev,
+			      struct aspeed_jtag *aspeed_jtag)
+{
+	aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_ISR);
+	/* Disable clock */
+	aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_CTRL);
+	reset_control_assert(aspeed_jtag->rst);
+	clk_disable_unprepare(aspeed_jtag->pclk);
+	return 0;
+}
+
+static const struct jtag_ops aspeed_jtag_ops = {
+	.freq_get = aspeed_jtag_freq_get,
+	.freq_set = aspeed_jtag_freq_set,
+	.status_get = aspeed_jtag_status_get,
+	.idle = aspeed_jtag_idle,
+	.xfer = aspeed_jtag_xfer,
+	.mode_set = aspeed_jtag_mode_set
+};
+
+static int aspeed_jtag_probe(struct platform_device *pdev)
+{
+	struct aspeed_jtag *aspeed_jtag;
+	struct jtag *jtag;
+	int err;
+
+	jtag = jtag_alloc(&pdev->dev, sizeof(*aspeed_jtag), &aspeed_jtag_ops);
+	if (!jtag)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, jtag);
+	aspeed_jtag = jtag_priv(jtag);
+	aspeed_jtag->dev = &pdev->dev;
+
+	/* Initialize device*/
+	err = aspeed_jtag_init(pdev, aspeed_jtag);
+	if (err)
+		goto err_jtag_init;
+
+	/* Initialize JTAG core structure*/
+	err = devm_jtag_register(aspeed_jtag->dev, jtag);
+	if (err)
+		goto err_jtag_register;
+
+	return 0;
+
+err_jtag_register:
+	aspeed_jtag_deinit(pdev, aspeed_jtag);
+err_jtag_init:
+	jtag_free(jtag);
+	return err;
+}
+
+static int aspeed_jtag_remove(struct platform_device *pdev)
+{
+	struct jtag *jtag = platform_get_drvdata(pdev);
+
+	aspeed_jtag_deinit(pdev, jtag_priv(jtag));
+	return 0;
+}
+
+static const struct of_device_id aspeed_jtag_of_match[] = {
+	{ .compatible = "aspeed,ast2400-jtag", },
+	{ .compatible = "aspeed,ast2500-jtag", },
+	{}
+};
+
+static struct platform_driver aspeed_jtag_driver = {
+	.probe = aspeed_jtag_probe,
+	.remove = aspeed_jtag_remove,
+	.driver = {
+		.name = ASPEED_JTAG_NAME,
+		.of_match_table = aspeed_jtag_of_match,
+	},
+};
+module_platform_driver(aspeed_jtag_driver);
+
+MODULE_AUTHOR("Oleksandr Shamray <oleksandrs@mellanox.com>");
+MODULE_DESCRIPTION("ASPEED JTAG driver");
+MODULE_LICENSE("GPL v2");
-- 
1.7.1

^ permalink raw reply related

* [patch v25 1/4] drivers: jtag: Add JTAG core driver
From: Oleksandr Shamray @ 2018-05-29 14:53 UTC (permalink / raw)
  To: gregkh, arnd
  Cc: linux-kernel, linux-arm-kernel, devicetree, openbmc, joel, jiri,
	tklauser, linux-serial, vadimp, system-sw-low-level, robh+dt,
	openocd-devel-owner, linux-api, davem, mchehab, Oleksandr Shamray
In-Reply-To: <1527605618-15705-1-git-send-email-oleksandrs@mellanox.com>

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@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Philippe Ombredanne <pombredanne@nexb.com>
---
v24->v25
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- set values to enums in jtag.h

v23->v24
Notifications from kbuild test robot <lkp@intel.com>
- Add include types.h header to jtag.h
- remove unecessary jtag_release

v22->v23
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- remove restriction of allocated JTAG devs-
- add validation fo idle values
- remove unnecessary blank line
- change retcode for xfer
- remove unecessary jtag_release callback
- remove unecessary  defined fron jtag.h
- align in one line define JTAG_IOCRUNTEST

v21->v22
Comments pointed by Andy Shevchenko <andy.shevchenko@gmail.com>
- Fix 0x0f -> 0x0F in ioctl-number.txt
- Add description to #define MAX_JTAG_NAME_LEN
- Remove unnecessary entry *dev from struct jtag
- Remove redundant parens
- Described mandatory callbacks and removed unnecessary
- Set JTAG_MAX_XFER_DATA_LEN to power of 2
- rework driver alloc/register to devm_ variant
- increasing line length up to 84 in order to improve readability.

Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- fix spell in ABI doccumentation

v20->v21
    Comments pointed by Randy Dunlap <rdunlap@infradead.org>
    - Fix JTAG dirver help in Kconfig

v19->v20
Comments pointed by Randy Dunlap <rdunlap@infradead.org>
- Fix JTAG dirver help in Kconfig

Notifications from kbuild test robot <lkp@intel.com>
- fix incompatible type casts

v18->v19
Comments pointed by Julia Cartwright <juliac@eso.teric.us>
- Fix memory leak on jtag_alloc exit

v17->v18
Comments pointed by Julia Cartwright <juliac@eso.teric.us>
- 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@eso.teric.us>
- Fix memory allocation on jtag alloc
- Move out unnecessary form lock on jtag open
- Rework jtag register behavior

v15->v16
Comments pointed by Florian Fainelli <f.fainelli@gmail.com>
- 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@nexb.com>
- Change style of head block comment from /**/ to //

v12->v13
Comments pointed by Philippe Ombredanne <pombredanne@nexb.com>
- 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@linuxfoundation.org>
- Change jtag.h licence type to
  SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note
  and reorder line with license in description

Comments pointed by Chip Bilbrey <chip@bilbrey.org>
- 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 single open per device blocking

v10->v11
Notifications from kbuild test robot <lkp@intel.com>
- Add include types.h header 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@linuxfoundation.org>
- 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@arndb.de>
- 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@ettus.com>
- Fix misspelling s/friver/driver

v6->v7
Notifications from kbuild test robot <lkp@intel.com>
- 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@arndb.de>
- 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@intel.com>
- Change include path to <linux/types.h> in jtag.h

v1->v2
Comments pointed by Greg KH <gregkh@linuxfoundation.org>
- 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@lunn.ch>
- Change list_add_tail in jtag_unregister to list_del

Comments pointed by Neil Armstrong <narmstrong@baylibre.com>
- Add SPDX-License-Identifier instead of license text

Comments pointed by Arnd Bergmann <arnd@arndb.de>
- 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@distanz.ch>
- 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                          |    8 +
 drivers/Kconfig                      |    2 +
 drivers/Makefile                     |    1 +
 drivers/jtag/Kconfig                 |   17 ++
 drivers/jtag/Makefile                |    1 +
 drivers/jtag/jtag.c                  |  274 ++++++++++++++++++++++++++++++++++
 include/linux/jtag.h                 |   41 +++++
 include/uapi/linux/jtag.h            |  109 ++++++++++++++
 9 files changed, 455 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..886e676 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@ratio.de>
 0xB1	00-1F	PPPoX			<mailto:mostrows@styx.uwaterloo.ca>
+0xB2	00-0F	linux/jtag.h		JTAG driver
+					<mailto:oleksandrs@mellanox.com>
 0xB3	00	linux/mmc/ioctl.h
 0xB4	00-0F	linux/gpio.h		<mailto:linux-gpio@vger.kernel.org>
 0xB5	00-0F	uapi/linux/rpmsg.h	<mailto:linux-remoteproc@vger.kernel.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 79bb02f..e7b8b2c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7610,6 +7610,14 @@ L:	linux-serial@vger.kernel.org
 S:	Maintained
 F:	drivers/tty/serial/jsm/
 
+JTAG SUBSYSTEM
+M:	Oleksandr Shamray <oleksandrs@mellanox.com>
+M:	Vadim Pasternak <vadimp@mellanox.com>
+S:	Maintained
+F:	include/linux/jtag.h
+F:	include/uapi/linux/jtag.h
+F:	drivers/jtag/
+
 K10TEMP HARDWARE MONITORING DRIVER
 M:	Clemens Ladisch <clemens@ladisch.de>
 L:	linux-hwmon@vger.kernel.org
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-$(CONFIG_JTAG)		+= jtag/
diff --git a/drivers/jtag/Kconfig b/drivers/jtag/Kconfig
new file mode 100644
index 0000000..47771fc
--- /dev/null
+++ b/drivers/jtag/Kconfig
@@ -0,0 +1,17 @@
+menuconfig JTAG
+	tristate "JTAG support"
+	help
+	  This provides basic core functionality support for JTAG class devices.
+	  Hardware that is equipped with a JTAG microcontroller can be
+	  supported by using this driver's interfaces.
+	  This driver exposes a set of IOCTLs to the user space for
+	  the following commands:
+	    SDR: Performs an IEEE 1149.1 Data Register scan
+	    SIR: Performs an IEEE 1149.1 Instruction Register scan.
+	    RUNTEST: Forces the IEEE 1149.1 bus to a run state for a specified
+	    number of clocks or a specified time period.
+
+	  If you want this support, you should say Y here.
+
+	  To compile this driver as a module, choose M here: the module will
+	  be called jtag.
diff --git a/drivers/jtag/Makefile b/drivers/jtag/Makefile
new file mode 100644
index 0000000..af37493
--- /dev/null
+++ b/drivers/jtag/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_JTAG)		+= jtag.o
diff --git a/drivers/jtag/jtag.c b/drivers/jtag/jtag.c
new file mode 100644
index 0000000..6657b84
--- /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@mellanox.com>
+
+#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>
+
+struct jtag {
+	struct miscdevice miscdev;
+	const struct jtag_ops *ops;
+	int id;
+	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;
+
+		if (idle.reset > JTAG_FORCE_RESET)
+			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 err;
+		}
+
+		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 (!jtag->ops->mode_set)
+			return -EOPNOTSUPP;
+
+		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);
+
+	file->private_data = jtag;
+	return nonseekable_open(inode, file);
+}
+
+static const struct file_operations jtag_fops = {
+	.owner		= THIS_MODULE,
+	.open		= jtag_open,
+	.llseek		= noop_llseek,
+	.unlocked_ioctl = jtag_ioctl,
+};
+
+struct jtag *jtag_alloc(struct device *host, size_t priv_size,
+			const struct jtag_ops *ops)
+{
+	struct jtag *jtag;
+
+	if (!host)
+		return NULL;
+
+	if (!ops)
+		return NULL;
+
+	if (!ops->idle || !ops->status_get || !ops->xfer)
+		return NULL;
+
+	jtag = kzalloc(sizeof(*jtag) + priv_size, GFP_KERNEL);
+	if (!jtag)
+		return NULL;
+
+	jtag->ops = ops;
+	jtag->miscdev.parent = host;
+
+	return jtag;
+}
+EXPORT_SYMBOL_GPL(jtag_alloc);
+
+void jtag_free(struct jtag *jtag)
+{
+	kfree(jtag);
+}
+EXPORT_SYMBOL_GPL(jtag_free);
+
+static int jtag_register(struct jtag *jtag)
+{
+	struct device *dev = jtag->miscdev.parent;
+	int err;
+	int id;
+
+	if (!dev)
+		return -ENODEV;
+
+	id = ida_simple_get(&jtag_ida, 0, 0, GFP_KERNEL);
+	if (id < 0)
+		return id;
+
+	jtag->id = id;
+
+	jtag->miscdev.fops =  &jtag_fops;
+	jtag->miscdev.minor = MISC_DYNAMIC_MINOR;
+	jtag->miscdev.name = kasprintf(GFP_KERNEL, "jtag%d", id);
+	if (!jtag->miscdev.name) {
+		err = -ENOMEM;
+		goto err_jtag_alloc;
+	}
+
+	err = misc_register(&jtag->miscdev);
+	if (err) {
+		dev_err(jtag->miscdev.parent, "Unable to register device\n");
+		goto err_jtag_name;
+	}
+	return 0;
+
+err_jtag_name:
+	kfree(jtag->miscdev.name);
+err_jtag_alloc:
+	ida_simple_remove(&jtag_ida, id);
+	return err;
+}
+
+static void jtag_unregister(struct jtag *jtag)
+{
+	misc_deregister(&jtag->miscdev);
+	kfree(jtag->miscdev.name);
+	ida_simple_remove(&jtag_ida, jtag->id);
+}
+
+static void devm_jtag_unregister(struct device *dev, void *res)
+{
+	jtag_unregister(*(struct jtag **)res);
+}
+
+int devm_jtag_register(struct device *dev, struct jtag *jtag)
+{
+	struct jtag **ptr;
+	int ret;
+
+	ptr = devres_alloc(devm_jtag_unregister, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return -ENOMEM;
+
+	ret = jtag_register(jtag);
+	if (!ret) {
+		*ptr = jtag;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(devm_jtag_register);
+
+static void __exit jtag_exit(void)
+{
+	ida_destroy(&jtag_ida);
+}
+
+module_exit(jtag_exit);
+
+MODULE_AUTHOR("Oleksandr Shamray <oleksandrs@mellanox.com>");
+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..fd5dd79
--- /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@mellanox.com>
+
+#ifndef __JTAG_H
+#define __JTAG_H
+
+#include <linux/types.h>
+#include <uapi/linux/jtag.h>
+
+#define JTAG_MAX_XFER_DATA_LEN 65535
+
+struct jtag;
+/**
+ * struct jtag_ops - callbacks for JTAG control functions:
+ *
+ * @freq_get: get frequency function. Filled by dev driver
+ * @freq_set: set frequency function. Filled by dev driver
+ * @status_get: set status function. Mandatory func. Filled by dev driver
+ * @idle: set JTAG to idle state function. Mandatory func. Filled by dev driver
+ * @xfer: send JTAG xfer function. Mandatory func. Filled by dev driver
+ * @mode_set: set specific work mode for JTAG. Filled by dev 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 devm_jtag_register(struct device *dev, struct jtag *jtag);
+struct jtag *jtag_alloc(struct device *host, 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..4f521b8
--- /dev/null
+++ b/include/uapi/linux/jtag.h
@@ -0,0 +1,109 @@
+// 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@mellanox.com>
+
+#ifndef __UAPI_LINUX_JTAG_H
+#define __UAPI_LINUX_JTAG_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 = 0,
+	JTAG_STATE_PAUSEIR = 1,
+	JTAG_STATE_PAUSEDR = 2,
+};
+
+/**
+ * enum jtag_reset:
+ *
+ * @JTAG_NO_RESET: JTAG run TAP from current state
+ * @JTAG_FORCE_RESET: JTAG force TAP to reset state
+ */
+enum jtag_reset {
+	JTAG_NO_RESET = 0,
+	JTAG_FORCE_RESET = 1,
+};
+
+/**
+ * enum jtag_xfer_type:
+ *
+ * @JTAG_SIR_XFER: SIR transfer
+ * @JTAG_SDR_XFER: SDR transfer
+ */
+enum jtag_xfer_type {
+	JTAG_SIR_XFER = 0,
+	JTAG_SDR_XFER = 1,
+};
+
+/**
+ * enum jtag_xfer_direction:
+ *
+ * @JTAG_READ_XFER: read transfer
+ * @JTAG_WRITE_XFER: write transfer
+ */
+enum jtag_xfer_direction {
+	JTAG_READ_XFER = 0,
+	JTAG_WRITE_XFER = 1,
+};
+
+/**
+ * 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 provide 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 provide interface to JTAG device for JTAG SDR/SIR 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)
+
+#endif /* __UAPI_LINUX_JTAG_H */
-- 
1.7.1

^ permalink raw reply related

* [patch v25 0/4] JTAG driver introduction
From: Oleksandr Shamray @ 2018-05-29 14:53 UTC (permalink / raw)
  To: gregkh, arnd
  Cc: system-sw-low-level, devicetree, jiri, vadimp, linux-api, openbmc,
	linux-kernel, openocd-devel-owner, robh+dt, joel, linux-serial,
	Oleksandr Shamray, tklauser, mchehab, davem, linux-arm-kernel

When a need raise up to use JTAG interface for system's devices
programming or CPU debugging, usually the user layer
application implements jtag protocol by bit-bang or using a 
proprietary connection to vendor hardware.
This method can be slow and not generic.
 
We propose to implement general JTAG interface and infrastructure
to communicate with user layer application. In such way, we can
have the standard JTAG interface core part and separation from
specific HW implementation.
This allow new capability to debug the CPU or program system's 
device via BMC without additional devices nor cost. 

This patch purpose is to add JTAG master core infrastructure by 
defining new JTAG class and provide generic JTAG interface
to allow hardware specific drivers to connect this interface.
This will enable all JTAG drivers to use the common interface
part and will have separate for hardware implementation.

The JTAG (Joint Test Action Group) core driver provides minimal generic
JTAG interface, which can be used by hardware specific JTAG master
controllers. By providing common interface for the JTAG controllers,
user space device programing is hardware independent.
 
Modern SoC which in use for embedded system' equipped with
internal JTAG master interface.
This interface is used for programming and debugging system's
hardware components, like CPLD, FPGA, CPU, voltage and
industrial controllers.
Firmware for such devices can be upgraded through JTAG interface during
Runtime. The JTAG standard support for multiple devices programming,
is in case their lines are daisy-chained together.

For example, systems which equipped with host CPU, BMC SoC or/and 
number of programmable devices are capable to connect a pin and
select system components dynamically for programming and debugging,
This is using by the BMC which is equipped with internal SoC master
controller.
For example:

BMC JTAG master --> pin selected to CPLDs chain for programming (filed
upgrade, production) 
BMC JTAG master --> pin selected to voltage monitors for programming 
(field upgrade, production) 
BMC JTAG master --> pin selected to host CPU (on-site debugging 
and developers debugging)

For example, we can have application in user space which using calls
to JTAG driver executes CPLD programming directly from SVF file
 
The JTAG standard (IEEE 1149.1) defines the next connector pins:
- TDI (Test Data In);
- TDO (Test Data Out);
- TCK (Test Clock);
- TMS (Test Mode Select);
- TRST (Test Reset) (Optional);

The SoC equipped with JTAG master controller, performs
device programming on command or vector level. For example
a file in a standard SVF (Serial Vector Format) that contains
boundary scan vectors, can be used by sending each vector
to the JTAG interface and the JTAG controller will execute
the programming.

Initial version provides the system calls set for:
- SIR (Scan Instruction Register, IEEE 1149.1 Instruction Register scan);
- SDR (Scan Data Register, IEEE 1149.1 Data Register scan);
- RUNTEST (Forces the IEEE 1149.1 bus to a run state for a specified
  number of clocks.

SoC which are not equipped with JTAG master interface, can be built
on top of JTAG core driver infrastructure, by applying bit-banging of
TDI, TDO, TCK and TMS pins within the hardware specific driver.

Oleksandr Shamray (4):
  drivers: jtag: Add JTAG core driver
  drivers: jtag: Add Aspeed SoC 24xx and 25xx families JTAG master
    driver
  Documentation: jtag: Add bindings for Aspeed SoC 24xx and 25xx
    families     JTAG master driver
  Documentation: jtag: Add ABI documentation

 Documentation/ABI/testing/gpio-cdev                |    1 -
 Documentation/ABI/testing/jtag-dev                 |   23 +
 .../devicetree/bindings/jtag/aspeed-jtag.txt       |   22 +
 Documentation/ioctl/ioctl-number.txt               |    2 +
 Documentation/jtag/overview                        |   27 +
 Documentation/jtag/transactions                    |  109 +++
 MAINTAINERS                                        |   10 +
 drivers/Kconfig                                    |    2 +
 drivers/Makefile                                   |    1 +
 drivers/jtag/Kconfig                               |   31 +
 drivers/jtag/Makefile                              |    2 +
 drivers/jtag/jtag-aspeed.c                         |  756 ++++++++++++++++++++
 drivers/jtag/jtag.c                                |  274 +++++++
 include/linux/jtag.h                               |   41 ++
 include/uapi/linux/jtag.h                          |  109 +++
 15 files changed, 1409 insertions(+), 1 deletions(-)
 create mode 100644 Documentation/ABI/testing/jtag-dev
 create mode 100644 Documentation/devicetree/bindings/jtag/aspeed-jtag.txt
 create mode 100644 Documentation/jtag/overview
 create mode 100644 Documentation/jtag/transactions
 create mode 100644 drivers/jtag/Kconfig
 create mode 100644 drivers/jtag/Makefile
 create mode 100644 drivers/jtag/jtag-aspeed.c
 create mode 100644 drivers/jtag/jtag.c
 create mode 100644 include/linux/jtag.h
 create mode 100644 include/uapi/linux/jtag.h

^ permalink raw reply

* Re: [PATCH v4 5/6] spi: at91-usart: add driver for at91-usart as spi
From: Nicolas Ferre @ 2018-05-29 14:36 UTC (permalink / raw)
  To: Radu Pirea, Andy Shevchenko
  Cc: Mark Brown, alexandre.belloni, Lee Jones, Richard Genoud,
	Rob Herring, Mark Rutland, Greg Kroah-Hartman, linux-spi,
	linux-arm Mailing List, Linux Kernel Mailing List, devicetree,
	open list:SERIAL DRIVERS, Ludovic Desroches
In-Reply-To: <0c529082-722c-14d8-7a04-dfeb63d5de92@microchip.com>

On 29/05/2018 at 16:34, Nicolas Ferre wrote:
> On 29/05/2018 at 16:28, Radu Pirea wrote:
>>
>>
>> On 05/28/2018 11:21 AM, Andy Shevchenko wrote:
>>> On Fri, May 25, 2018 at 8:19 PM, Radu Pirea <radu.pirea@microchip.com> wrote:
>>>> This is the driver for at91-usart in spi mode. The USART IP can be configured
>>>> to work in many modes and one of them is SPI.
> 
> [..]
> 
>>>> +static int at91_usart_gpio_setup(struct platform_device *pdev)
>>>> +{
>>>
>>>> +       struct device_node      *np = pdev->dev.parent->of_node;
>>>
>>> Your driver is not OF specific as far as I can see. Drop all these
>>> device_node stuff and change API calls respectively.
>>
>> Ok. What do you suggest to use instead of OF API to get the count of
>> cs-gpios and to read their values one by one?
> 
> As Alexandre said, we can make this driver OF specific.
> 
> What could be interesting is to use the gpio descriptors API and not the
> older one. This would allow us to have far more control over the gpio
> that we use in our drivers (Ludovic is converting our drivers to only
> use gpiod structures).

Oh, but we already said that we cannot.
Disregard my comment then, sorry for the noise.

> Regards,
>     Nicolas
> 
>>
>>>
>>>> +       int                     i;
>>>
>>>> +       int                     ret = 0;
>>>> +       int                     nb = 0;
>>>
>>> What happened to indentation?
>>>
>>> Redundnant assignment for both.
>>>
>>>> +       if (!np)
>>>> +               return -EINVAL;
>>>> +
>>>> +       nb = of_gpio_named_count(np, "cs-gpios");
>>>> +       for (i = 0; i < nb; i++) {
>>>> +               int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
>>>> +
>>>> +               if (cs_gpio < 0)
>>>> +                       return cs_gpio;
>>>> +
>>>> +               if (gpio_is_valid(cs_gpio)) {
>>>> +                       ret = devm_gpio_request_one(&pdev->dev, cs_gpio,
>>>> +                                                   GPIOF_DIR_OUT,
>>>> +                                                   dev_name(&pdev->dev));
>>>> +                       if (ret)
>>>> +                               return ret;
>>>> +               }
>>>> +       }
>>>> +
>>>> +       return 0;
>>>> +}
> [..]
> 


-- 
Nicolas Ferre

^ permalink raw reply

* Re: [PATCH v4 5/6] spi: at91-usart: add driver for at91-usart as spi
From: Nicolas Ferre @ 2018-05-29 14:34 UTC (permalink / raw)
  To: Radu Pirea, Andy Shevchenko
  Cc: Mark Brown, alexandre.belloni, Lee Jones, Richard Genoud,
	Rob Herring, Mark Rutland, Greg Kroah-Hartman, linux-spi,
	linux-arm Mailing List, Linux Kernel Mailing List, devicetree,
	open list:SERIAL DRIVERS, Ludovic Desroches
In-Reply-To: <110bb353-b131-348c-8e26-9863b074142d@microchip.com>

On 29/05/2018 at 16:28, Radu Pirea wrote:
> 
> 
> On 05/28/2018 11:21 AM, Andy Shevchenko wrote:
>> On Fri, May 25, 2018 at 8:19 PM, Radu Pirea <radu.pirea@microchip.com> wrote:
>>> This is the driver for at91-usart in spi mode. The USART IP can be configured
>>> to work in many modes and one of them is SPI.

[..]

>>> +static int at91_usart_gpio_setup(struct platform_device *pdev)
>>> +{
>>
>>> +       struct device_node      *np = pdev->dev.parent->of_node;
>>
>> Your driver is not OF specific as far as I can see. Drop all these
>> device_node stuff and change API calls respectively.
> 
> Ok. What do you suggest to use instead of OF API to get the count of
> cs-gpios and to read their values one by one?

As Alexandre said, we can make this driver OF specific.

What could be interesting is to use the gpio descriptors API and not the 
older one. This would allow us to have far more control over the gpio 
that we use in our drivers (Ludovic is converting our drivers to only 
use gpiod structures).

Regards,
   Nicolas

> 
>>
>>> +       int                     i;
>>
>>> +       int                     ret = 0;
>>> +       int                     nb = 0;
>>
>> What happened to indentation?
>>
>> Redundnant assignment for both.
>>
>>> +       if (!np)
>>> +               return -EINVAL;
>>> +
>>> +       nb = of_gpio_named_count(np, "cs-gpios");
>>> +       for (i = 0; i < nb; i++) {
>>> +               int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
>>> +
>>> +               if (cs_gpio < 0)
>>> +                       return cs_gpio;
>>> +
>>> +               if (gpio_is_valid(cs_gpio)) {
>>> +                       ret = devm_gpio_request_one(&pdev->dev, cs_gpio,
>>> +                                                   GPIOF_DIR_OUT,
>>> +                                                   dev_name(&pdev->dev));
>>> +                       if (ret)
>>> +                               return ret;
>>> +               }
>>> +       }
>>> +
>>> +       return 0;
>>> +}
[..]

-- 
Nicolas Ferre

^ permalink raw reply

* Re: [PATCH v4 5/6] spi: at91-usart: add driver for at91-usart as spi
From: Radu Pirea @ 2018-05-29 14:28 UTC (permalink / raw)
  To: Andy Shevchenko
  Cc: Mark Brown, Nicolas Ferre, alexandre.belloni, Lee Jones,
	Richard Genoud, Rob Herring, Mark Rutland, Greg Kroah-Hartman,
	linux-spi, linux-arm Mailing List, Linux Kernel Mailing List,
	devicetree, open list:SERIAL DRIVERS
In-Reply-To: <CAHp75Vc0e=+2YptoFAUuPSpAyxaCUJJqjQPPY5VZHV=MEMOqHQ@mail.gmail.com>



On 05/28/2018 11:21 AM, Andy Shevchenko wrote:
> On Fri, May 25, 2018 at 8:19 PM, Radu Pirea <radu.pirea@microchip.com> wrote:
>> This is the driver for at91-usart in spi mode. The USART IP can be configured
>> to work in many modes and one of them is SPI.
>>
>> The driver was tested on sama5d3-xplained and sama5d4-xplained boards with
>> enc28j60 ethernet controller as slave.
> 
>> +#include <linux/of_gpio.h>
> 
> What is the use of it?

I need of_gpio.h for of_gpio_named_count, of_get_named_gpio and 
devm_gpio_request_one(found in gpio.h)

> 
>> +#define US_INIT                        (US_MR_SPI_MASTER | US_MR_CHRL | US_MR_CLKO | \
>> +                               US_MR_WRDBT)
> 
> Don't split lines like this, it's hard to read.
> 
> #define FOO \
>   (BAR1 | BAR2)

I'll fix it.

> 
> I think I already told this to someone recently, maybe to you.
> 
>> +/* Register access macros */
>> +#define spi_readl(port, reg) \
>> +       readl_relaxed((port)->regs + US_##reg)
>> +#define spi_writel(port, reg, value) \
>> +       writel_relaxed((value), (port)->regs + US_##reg)
>> +
>> +#define spi_readb(port, reg) \
>> +       readb_relaxed((port)->regs + US_##reg)
>> +#define spi_writeb(port, reg, value) \
>> +       writeb_relaxed((value), (port)->regs + US_##reg)
> 
> Names are too generic. You better to use the same prefix as for the
> rest, i.e. at91_spi_

Good ideea. I will change the names.

> 
>> +       /*used in interrupt to protect data reading*/
> 
> Comment style.
> 
> You need to read some existing code, perhaps, to see how it's done.

Ok. I will add the comment.

> 
>> +static inline void at91_usart_spi_tx(struct at91_usart_spi *aus)
>> +{
>> +       unsigned int len = aus->current_transfer->len;
>> +       unsigned int remaining = aus->current_tx_remaining_bytes;
>> +       const u8  *tx_buf = aus->current_transfer->tx_buf;
>> +
> 
>> +       if (remaining)
>> +               if (at91_usart_spi_tx_ready(aus)) {
> 
> if (x) {
>   if (y) {
> ...
>   }
> }
> 
> is equivalent to if (x && y) {}.
> 
> Though, considering your intention here, I would rather go with better
> pattern, i.e.
> 
> if (!remaining)
>   return;

Thank for suggestion. I will change.

> 
>> +                       spi_writeb(aus, THR, tx_buf[len - remaining]);
>> +                       aus->current_tx_remaining_bytes--;
>> +               }
>> +}
>> +
>> +static inline void at91_usart_spi_rx(struct at91_usart_spi *aus)
>> +{
> 
>> +       if (remaining) {
>> +               rx_buf[len - remaining] = spi_readb(aus, RHR);
>> +               aus->current_rx_remaining_bytes--;
>> +       }
> 
> Ditto.
> 
>> +}
> 
> 
>> +static int at91_usart_gpio_setup(struct platform_device *pdev)
>> +{
> 
>> +       struct device_node      *np = pdev->dev.parent->of_node;
> 
> Your driver is not OF specific as far as I can see. Drop all these
> device_node stuff and change API calls respectively.

Ok. What do you suggest to use instead of OF API to get the count of 
cs-gpios and to read their values one by one?

> 
>> +       int                     i;
> 
>> +       int                     ret = 0;
>> +       int                     nb = 0;
> 
> What happened to indentation?
> 
> Redundnant assignment for both.
> 
>> +       if (!np)
>> +               return -EINVAL;
>> +
>> +       nb = of_gpio_named_count(np, "cs-gpios");
>> +       for (i = 0; i < nb; i++) {
>> +               int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
>> +
>> +               if (cs_gpio < 0)
>> +                       return cs_gpio;
>> +
>> +               if (gpio_is_valid(cs_gpio)) {
>> +                       ret = devm_gpio_request_one(&pdev->dev, cs_gpio,
>> +                                                   GPIOF_DIR_OUT,
>> +                                                   dev_name(&pdev->dev));
>> +                       if (ret)
>> +                               return ret;
>> +               }
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +static int at91_usart_spi_probe(struct platform_device *pdev)
>> +{
> 
>> +       regs = platform_get_resource(to_platform_device(pdev->dev.parent),
>> +                                    IORESOURCE_MEM, 0);
>> +       if (!regs)
>> +               return -EINVAL;
> 
> This looks weird. Supply resource to _this_ device in your MFD code.

I know weird, but is the safest way to pass the resource and the of_node.

> 
>> +       dev_info(&pdev->dev,
>> +                "Atmel USART SPI Controller version 0x%x at 0x%08lx (irq %d)\n",
>> +                spi_readl(aus, VERSION),
>> +                (unsigned long)regs->start, irq);
> 
> I think I already told you, don't use explicit casting when print.
> If it wasn't you, do you homework then. But above is no go. >
>> +       return 0;
> 
>> +static struct platform_driver at91_usart_spi_driver = {
>> +       .driver = {
>> +               .name = "at91_usart_spi",
> 
>> +               .of_match_table = of_match_ptr(at91_usart_spi_dt_ids),
> 
> Drop of_match_ptr(). It's not needed.
> 
>> +       },
>> +       .probe = at91_usart_spi_probe,
> 
>> +       .remove = at91_usart_spi_remove, };
> 
> Already told ya, split lines correctly.
> 

^ permalink raw reply

* Re: [patch v23 2/4] drivers: jtag: Add Aspeed SoC 24xx and 25xx families JTAG master driver
From: Greg KH @ 2018-05-29 13:11 UTC (permalink / raw)
  To: Oleksandr Shamray
  Cc: arnd, linux-kernel, linux-arm-kernel, devicetree, openbmc, joel,
	jiri, tklauser, linux-serial, vadimp, system-sw-low-level,
	robh+dt, openocd-devel-owner, linux-api, davem, mchehab
In-Reply-To: <1527594545-19870-3-git-send-email-oleksandrs@mellanox.com>

On Tue, May 29, 2018 at 02:49:03PM +0300, Oleksandr Shamray wrote:
> +static int aspeed_jtag_idle(struct jtag *jtag,
> +			    struct jtag_run_test_idle *runtest)
> +{
> +	struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
> +
> +	dev_dbg(aspeed_jtag->dev, "runtest, status:%d, mode:%s, state:%s, reset:%d, tck:%d\n",
> +		aspeed_jtag->status,
> +		aspeed_jtag->mode & JTAG_XFER_HW_MODE ? "HW" : "SW",
> +		end_status_str[runtest->endstate], runtest->reset,
> +		runtest->tck);

You have dev_dbg() lines all over the place.  They can all be removed
now, right?  ftrace works well, and if you really want to do this
properly, use tracepoints in the jtag core code so that you can get the
information for all devices as needed.

But don't put them all over the driver, now that it's all working,
there's no need, right?

> +static void aspeed_jtag_xfer_push_data_last(struct aspeed_jtag *aspeed_jtag,
> +					    enum jtag_xfer_type type,
> +					    u32 shift_bits,
> +					    enum jtag_endstate endstate)
> +{
> +	if (endstate == JTAG_STATE_IDLE) {
> +		if (type == JTAG_SIR_XFER) {
> +			dev_dbg(aspeed_jtag->dev, "IR Keep Pause\n");

Like this, doesn't provide much info, does it?

thanks,

greg k-h

^ permalink raw reply


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