* [PATCH v3 2/4] dt-bindings: mtk-sysirq: Add compatible for Mediatek MT8183
From: Erin Lo @ 2018-05-17 6:22 UTC (permalink / raw)
To: Matthias Brugger, Rob Herring, Mark Rutland, Thomas Gleixner,
Jason Cooper, Marc Zyngier, Greg Kroah-Hartman
Cc: devicetree, srv_heupstream, linux-kernel, linux-serial,
linux-mediatek, linux-arm-kernel, yingjoe.chen, erin.lo,
mars.cheng
In-Reply-To: <1526538126-51497-1-git-send-email-erin.lo@mediatek.com>
This adds dt-binding documentation of SYSIRQ for Mediatek MT8183 SoC
Platform.
Signed-off-by: Erin Lo <erin.lo@mediatek.com>
---
.../devicetree/bindings/interrupt-controller/mediatek,sysirq.txt | 1 +
1 file changed, 1 insertion(+)
diff --git a/Documentation/devicetree/bindings/interrupt-controller/mediatek,sysirq.txt b/Documentation/devicetree/bindings/interrupt-controller/mediatek,sysirq.txt
index 07bf0b9..5ff48a8 100644
--- a/Documentation/devicetree/bindings/interrupt-controller/mediatek,sysirq.txt
+++ b/Documentation/devicetree/bindings/interrupt-controller/mediatek,sysirq.txt
@@ -5,6 +5,7 @@ interrupt.
Required properties:
- compatible: should be
+ "mediatek,mt8183-sysirq", "mediatek,mt6577-sysirq": for MT8183
"mediatek,mt8173-sysirq", "mediatek,mt6577-sysirq": for MT8173
"mediatek,mt8135-sysirq", "mediatek,mt6577-sysirq": for MT8135
"mediatek,mt8127-sysirq", "mediatek,mt6577-sysirq": for MT8127
--
1.9.1
^ permalink raw reply related
* [PATCH v3 1/4] dt-bindings: arm: Add bindings for Mediatek MT8183 SoC Platform
From: Erin Lo @ 2018-05-17 6:22 UTC (permalink / raw)
To: Matthias Brugger, Rob Herring, Mark Rutland, Thomas Gleixner,
Jason Cooper, Marc Zyngier, Greg Kroah-Hartman
Cc: devicetree, srv_heupstream, linux-kernel, linux-serial,
linux-mediatek, linux-arm-kernel, yingjoe.chen, erin.lo,
mars.cheng
In-Reply-To: <1526538126-51497-1-git-send-email-erin.lo@mediatek.com>
This adds dt-binding documentation of cpu for Mediatek MT8183.
Signed-off-by: Erin Lo <erin.lo@mediatek.com>
---
Documentation/devicetree/bindings/arm/mediatek.txt | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/Documentation/devicetree/bindings/arm/mediatek.txt b/Documentation/devicetree/bindings/arm/mediatek.txt
index 7d21ab3..2754535 100644
--- a/Documentation/devicetree/bindings/arm/mediatek.txt
+++ b/Documentation/devicetree/bindings/arm/mediatek.txt
@@ -19,6 +19,7 @@ compatible: Must contain one of
"mediatek,mt8127"
"mediatek,mt8135"
"mediatek,mt8173"
+ "mediatek,mt8183"
Supported boards:
@@ -73,3 +74,6 @@ Supported boards:
- MTK mt8173 tablet EVB:
Required root node properties:
- compatible = "mediatek,mt8173-evb", "mediatek,mt8173";
+- Evaluation board for MT8183:
+ Required root node properties:
+ - compatible = "mediatek,mt8183-evb", "mediatek,mt8183";
--
1.9.1
^ permalink raw reply related
* [PATCH v3 0/4] Add basic support for Mediatek MT8183 SoC
From: Erin Lo @ 2018-05-17 6:22 UTC (permalink / raw)
To: Matthias Brugger, Rob Herring, Mark Rutland, Thomas Gleixner,
Jason Cooper, Marc Zyngier, Greg Kroah-Hartman
Cc: devicetree-u79uwXL29TY76Z2rM5mHXA, srv_heupstream,
erin.lo-NuS5LvNUpcJWk0Htik3J/w,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
linux-mediatek-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r,
linux-serial-u79uwXL29TY76Z2rM5mHXA,
mars.cheng-NuS5LvNUpcJWk0Htik3J/w,
yingjoe.chen-NuS5LvNUpcJWk0Htik3J/w,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r
MT8183 is a SoC based on 64bit ARMv8 architecture.
It contains 4 CA53 and 4 CA73 cores.
MT8183 share many HW IP with MT65xx series.
This patchset was tested on MT8183 evaluation board, and boot to shell ok.
This series contains document bindings, device tree including interrupt, uart.
Change in v3:
1. Fill out GICC, GICH, GICV regions
2. Update Copyright to 2018
Change in v2:
1. Split dt-bindings into different patches
2. Correct bindings for supported SoCs (mtk-uart.txt)
Ben Ho (1):
arm64: dts: Add Mediatek SoC MT8183 and evaluation board dts and
Makefile
Erin Lo (3):
dt-bindings: arm: Add bindings for Mediatek MT8183 SoC Platform
dt-bindings: mtk-sysirq: Add compatible for Mediatek MT8183
dt-bindings: serial: Add compatible for Mediatek MT8183
Documentation/devicetree/bindings/arm/mediatek.txt | 4 +
.../interrupt-controller/mediatek,sysirq.txt | 1 +
.../devicetree/bindings/serial/mtk-uart.txt | 1 +
arch/arm64/boot/dts/mediatek/Makefile | 1 +
arch/arm64/boot/dts/mediatek/mt8183-evb.dts | 31 ++++
arch/arm64/boot/dts/mediatek/mt8183.dtsi | 182 +++++++++++++++++++++
6 files changed, 220 insertions(+)
create mode 100644 arch/arm64/boot/dts/mediatek/mt8183-evb.dts
create mode 100644 arch/arm64/boot/dts/mediatek/mt8183.dtsi
--
1.9.1
^ permalink raw reply
* Re: [PATCH v3 5/6] spi: at91-usart: add driver for at91-usart as spi
From: Mark Brown @ 2018-05-17 5:04 UTC (permalink / raw)
To: Radu Pirea
Cc: devicetree, linux-serial, linux-kernel, linux-arm-kernel,
linux-spi, mark.rutland, robh+dt, lee.jones, gregkh, jslaby,
richard.genoud, alexandre.belloni, nicolas.ferre
In-Reply-To: <20180511103822.31698-6-radu.pirea@microchip.com>
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On Fri, May 11, 2018 at 01:38:21PM +0300, Radu Pirea wrote:
> +config SPI_AT91_USART
> + tristate "Atmel USART Controller as SPI"
> + depends on HAS_DMA
> + depends on (ARCH_AT91 || COMPILE_TEST)
> + select MFD_AT91_USART
> + help
> + This selects a driver for the AT91 USART Controller as SPI Master,
> + present on AT91 and SAMA5 SoC series.
> +
This looks like there's some tab/space mixing going on here.
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for AT91 USART Controllers as SPI
> + *
> + * Copyright (C) 2018 Microchip Technology Inc.
Make the entire block a C++ comment so it looks more intentional rather
tha mixing C and C++.
> +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 (tx_buf && remaining) {
> + if (at91_usart_spi_tx_ready(aus))
> + spi_writel(aus, THR, tx_buf[len - remaining]);
> + aus->current_tx_remaining_bytes--;
Missing braces here - we only write to the FIFO if there's space but we
unconditionally decrement the counter.
> + } else {
> + if (at91_usart_spi_tx_ready(aus))
> + spi_writel(aus, THR, US_DUMMY_TX);
> + }
> +}
This looks like you're open coding SPI_CONTROLLER_MUST_TX
> + int len = aus->current_transfer->len;
> + int remaining = aus->current_rx_remaining_bytes;
> + u8 *rx_buf = aus->current_transfer->rx_buf;
> +
> + if (aus->current_rx_remaining_bytes) {
> + rx_buf[len - remaining] = spi_readb(aus, RHR);
> + aus->current_rx_remaining_bytes--;
> + } else {
> + spi_readb(aus, RHR);
> + }
Similarly for _MUST_RX.
> + controller->flags = SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX;
You're actually setting both flags... this means that the handling for
cases with missing TX or RX buffers can't happen.
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^ permalink raw reply
* Re: [PATCH v3 5/6] spi: at91-usart: add driver for at91-usart as spi
From: Mark Brown @ 2018-05-17 4:54 UTC (permalink / raw)
To: Radu Pirea
Cc: Andy Shevchenko, devicetree, open list:SERIAL DRIVERS,
Linux Kernel Mailing List, linux-arm Mailing List, linux-spi,
Mark Rutland, Rob Herring, Lee Jones, Greg Kroah-Hartman,
Jiri Slaby, Richard Genoud, alexandre.belloni, Nicolas Ferre
In-Reply-To: <c23cdde58b9f724f51787c6c38478df983be6efa.camel@microchip.com>
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On Tue, May 15, 2018 at 12:22:24PM +0300, Radu Pirea wrote:
> On Mon, 2018-05-14 at 20:38 +0300, Andy Shevchenko wrote:
> > So, what is not going as expected in "SPI core takes care of CSs"
> > case?
> > Did you use oscilloscope for that?
> Yes, I used and CSs was not asserted. Anyway, I will will try again.
If the core chip select handling is not working properly for some reason
then the core chip select handling should be fixed rather than just open
coding in your driver - probably it's also broken for other users.
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^ permalink raw reply
* Re: [PATCH v1 3/3] serial: 8250_port: Disable DMA operations for kernel console
From: Sebastian Andrzej Siewior @ 2018-05-16 18:20 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Petr Mladek, Sergey Senozhatsky, Steven Rostedt, linux-kernel,
Greg Kroah-Hartman, Jiri Slaby, linux-serial, Arnd Bergmann
In-Reply-To: <171c11a999e2d9580d3783588d20b58e753c89ef.camel@linux.intel.com>
On 2018-05-16 15:58:10 [+0300], Andy Shevchenko wrote:
> > > It will be too tricky and error prone to allow DMA operations on
> > > kernel
> > > console.
> >
> > Why is it tricky and error prone? I had it working…
>
> On OMAP only? Had you tested this on let's say Intel Cherrytrail where
> DMA controller is a separate PCI device which needs to be handled
> separately from UART IP.
My point was simply to clarify if this entirely broken and requires
backports or if this makes things more complicated and could be avoided.
> > But I don't mind dropping the DMA on the kernel console because I
> > doubt
> > that we lose something here by disabling it. I would even imagine that
> > it gets "simpler" (maybe what you tried to say by "error prone") to
> > print something in the NMI case by writing directly to the FIFO
> > register
> > instead setting up a DMA transfer and so on.
>
> "error prone" mostly refers to patch 2 commit message. Here it seems I
> need to put something like above to explain why DMA case tricky _as
> well_.
Yes, full context is helpful :)
Sebastian
^ permalink raw reply
* Re: [patch v21 4/4] Documentation: jtag: Add ABI documentation
From: Randy Dunlap @ 2018-05-16 18:16 UTC (permalink / raw)
To: Oleksandr Shamray, 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
In-Reply-To: <1526394095-5069-5-git-send-email-oleksandrs@mellanox.com>
On 05/15/2018 07:21 AM, Oleksandr Shamray wrote:
> Added document that describe the ABI for JTAG class drivrer
>
> ---
> Documentation/ABI/testing/jtag-dev | 27 +++++++++
> Documentation/jtag/overview | 28 +++++++++
> Documentation/jtag/transactions | 109 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 164 insertions(+), 0 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..a86f188
> --- /dev/null
> +++ b/Documentation/jtag/overview
> @@ -0,0 +1,28 @@
> +Linux kernel JTAG support
> +=========================
> +
> +The JTAG is an industry standard for verifying hardware
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 hw specific 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..6a857c8
> --- /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
/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. Only one open operation per JTAG device
> +can be performed. Two or more open for one device will return error
will return error.
> +
> +Open/Close device:
> +- open("/dev/jtag0", O_RDWR);
> +- close(jtag_fd');
close(jtag_fd);
> +
> +ioctl()
> +-------
> +All access operations to JTAG devices performed through ioctl interface.
> +The IOCTL interface supports this requests:
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: 0 - run IDLE/PAUSE from current state
> + 1 - 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 len 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 hw driver can support different running modes you can change it.
If hardware driver
> +
> +Example:
> + unsigned int mode;
> + mode = JTAG_XFER_HW_MODE;
> + ioctl(jtag_fd, JTAG_SIOCMODE, &mode);
>
--
~Randy
^ permalink raw reply
* Re: [PATCH v1 0/3] console, serial8250: Disable PM and DMA ops
From: Andy Shevchenko @ 2018-05-16 13:10 UTC (permalink / raw)
To: Sebastian Andrzej Siewior, Andy Shevchenko
Cc: Petr Mladek, Sergey Senozhatsky, Steven Rostedt,
Linux Kernel Mailing List, Greg Kroah-Hartman, Jiri Slaby,
open list:SERIAL DRIVERS, Arnd Bergmann, Tony Lindgren
In-Reply-To: <20180516104734.357oevogppu5bsg4@linutronix.de>
On Wed, 2018-05-16 at 12:47 +0200, Sebastian Andrzej Siewior wrote:
> On 2018-05-16 13:17:36 [+0300], Andy Shevchenko wrote:
> > > The output is usually short so there
> > > shouldn't be much benefit from using it.
> > > I remember Tony wanted runtime-pm on the kernel console, too. And
> > > he
> > > told me explicit how to test it so that it works. Once the UART
> > > goes
> > > into PM (down), the whole IP block can go into power save mode.
> > > The
> > > board can be woken up by sending a character via the UART. The
> > > first few
> > > (incoming / read) characters are lost until the IP block is up
> > > again the
> > > frequency stable. This is known / expected.
> >
> > Don't consider world the OMAP only. The things more complicated if
> > we
> > go out of it. Which I tried to explain in the commit message of
> > patch
> > 2.
>
> I am not saying the world is OMAP only. I just tried to explain how
> any
> why it got there and its purpose. I haven't NACKed it. I would believe
> that with that information and Tony not defending his use case or
> possible change it somehow so it is not standing in your way, Greg
> would
> have enough information to go your way.
Yes, I got it.
> But since I am on it. You have to enable runtime-PM for the UART. So
> what is the problem if you simply don't enable it for the UART which
> used as the kernel console?
How do I know at the ->probe() time that device in question is going to
be kernel console? Maybe I missed simple way of it.
> From reading the description of #2, my understanding is that you are
> afraid that enabling the UART (bringing it from power-down mode) might
> take too long because it requires (or might require) an ACPI function
> call. This brings me again to: why bother and enable it in the first
> place? Because this might not work from NMI context.
> From looking at #2. You remove put/get in console_write()
...which must be removed in any case...
> and avoid
> runtime PM by pm_runtime_get_noresume() and need the extra hook on
> console exit. I wasn't aware that you can remove the console at
> runtime
> (and assumed you have to stick to what said in console= at bootime).
> Because if that is the case, you could simply strip UART_CAP_RPM and
> then there is no more runtime-PM for you. Or is it too simple and I
> miss something here?
See above question. IIRC it's either too early or too late to decide on
per port basis.
>
> > > In order to achieve the same thing you would have to disable the
> > > kernel
> > > console on that UART. I leave this to Tony.
> >
> > Precisely the point of the series.
Besides above this would be needed _at least_ for several 8250 glue
drivers, so, I decide to go once for all.
>
> Sebastian
--
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy
^ permalink raw reply
* Re: [PATCH v1 3/3] serial: 8250_port: Disable DMA operations for kernel console
From: Andy Shevchenko @ 2018-05-16 12:58 UTC (permalink / raw)
To: Sebastian Andrzej Siewior
Cc: Petr Mladek, Sergey Senozhatsky, Steven Rostedt, linux-kernel,
Greg Kroah-Hartman, Jiri Slaby, linux-serial, Arnd Bergmann
In-Reply-To: <20180516105553.h7e2buanqfxxya4e@linutronix.de>
On Wed, 2018-05-16 at 12:55 +0200, Sebastian Andrzej Siewior wrote:
> On 2018-05-15 21:34:09 [+0300], Andy Shevchenko wrote:
Thanks for review, my answers below.
> > It will be too tricky and error prone to allow DMA operations on
> > kernel
> > console.
>
> Why is it tricky and error prone? I had it working…
On OMAP only? Had you tested this on let's say Intel Cherrytrail where
DMA controller is a separate PCI device which needs to be handled
separately from UART IP.
> But I don't mind dropping the DMA on the kernel console because I
> doubt
> that we lose something here by disabling it. I would even imagine that
> it gets "simpler" (maybe what you tried to say by "error prone") to
> print something in the NMI case by writing directly to the FIFO
> register
> instead setting up a DMA transfer and so on.
"error prone" mostly refers to patch 2 commit message. Here it seems I
need to put something like above to explain why DMA case tricky _as
well_.
> > Disable any kind of DMA operations in such case.
> >
> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> > ---
> > drivers/tty/serial/8250/8250_port.c | 5 ++++-
> > 1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/tty/serial/8250/8250_port.c
> > b/drivers/tty/serial/8250/8250_port.c
> > index db97222a1bf4..9a4696ea728b 100644
> > --- a/drivers/tty/serial/8250/8250_port.c
> > +++ b/drivers/tty/serial/8250/8250_port.c
> > @@ -2371,7 +2371,10 @@ int serial8250_do_startup(struct uart_port
> > *port)
> > * Request DMA channels for both RX and TX.
> > */
> > if (up->dma) {
> > - retval = serial8250_request_dma(up);
> > + if (uart_console(port))
> > + retval = -ENXIO;
> > + else
> > + retval = serial8250_request_dma(up);
> > if (retval)
> > pr_warn_ratelimited("ttyS%d - failed to
> > request DMA\n",
> > serial_index(port));
>
> I would appreciate if you note that it is disabled on purpose and not
> because something failed.
> Other than those minor things I an board :)
Got it for v2.
>
> > --
> > 2.17.0
>
> Sebastian
--
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy
^ permalink raw reply
* Re: [PATCH v1 3/3] serial: 8250_port: Disable DMA operations for kernel console
From: Sebastian Andrzej Siewior @ 2018-05-16 10:55 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Petr Mladek, Sergey Senozhatsky, Steven Rostedt, linux-kernel,
Greg Kroah-Hartman, Jiri Slaby, linux-serial, Arnd Bergmann
In-Reply-To: <20180515183409.78046-4-andriy.shevchenko@linux.intel.com>
On 2018-05-15 21:34:09 [+0300], Andy Shevchenko wrote:
> It will be too tricky and error prone to allow DMA operations on kernel
> console.
Why is it tricky and error prone? I had it working…
But I don't mind dropping the DMA on the kernel console because I doubt
that we lose something here by disabling it. I would even imagine that
it gets "simpler" (maybe what you tried to say by "error prone") to
print something in the NMI case by writing directly to the FIFO register
instead setting up a DMA transfer and so on.
> Disable any kind of DMA operations in such case.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> drivers/tty/serial/8250/8250_port.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
> index db97222a1bf4..9a4696ea728b 100644
> --- a/drivers/tty/serial/8250/8250_port.c
> +++ b/drivers/tty/serial/8250/8250_port.c
> @@ -2371,7 +2371,10 @@ int serial8250_do_startup(struct uart_port *port)
> * Request DMA channels for both RX and TX.
> */
> if (up->dma) {
> - retval = serial8250_request_dma(up);
> + if (uart_console(port))
> + retval = -ENXIO;
> + else
> + retval = serial8250_request_dma(up);
> if (retval)
> pr_warn_ratelimited("ttyS%d - failed to request DMA\n",
> serial_index(port));
I would appreciate if you note that it is disabled on purpose and not
because something failed.
Other than those minor things I an board :)
> --
> 2.17.0
Sebastian
^ permalink raw reply
* Re: [PATCH v1 0/3] console, serial8250: Disable PM and DMA ops
From: Sebastian Andrzej Siewior @ 2018-05-16 10:47 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Andy Shevchenko, Petr Mladek, Sergey Senozhatsky, Steven Rostedt,
Linux Kernel Mailing List, Greg Kroah-Hartman, Jiri Slaby,
open list:SERIAL DRIVERS, Arnd Bergmann, Tony Lindgren
In-Reply-To: <CAHp75Vc2bJQHiWYcdKK+7wwMw2fSWxMauxP-dMRUAUdKnet7WQ@mail.gmail.com>
On 2018-05-16 13:17:36 [+0300], Andy Shevchenko wrote:
> > The output is usually short so there
> > shouldn't be much benefit from using it.
>
> > I remember Tony wanted runtime-pm on the kernel console, too. And he
> > told me explicit how to test it so that it works. Once the UART goes
> > into PM (down), the whole IP block can go into power save mode. The
> > board can be woken up by sending a character via the UART. The first few
> > (incoming / read) characters are lost until the IP block is up again the
> > frequency stable. This is known / expected.
>
> Don't consider world the OMAP only. The things more complicated if we
> go out of it. Which I tried to explain in the commit message of patch
> 2.
I am not saying the world is OMAP only. I just tried to explain how any
why it got there and its purpose. I haven't NACKed it. I would believe
that with that information and Tony not defending his use case or
possible change it somehow so it is not standing in your way, Greg would
have enough information to go your way.
But since I am on it. You have to enable runtime-PM for the UART. So
what is the problem if you simply don't enable it for the UART which
used as the kernel console?
>From reading the description of #2, my understanding is that you are
afraid that enabling the UART (bringing it from power-down mode) might
take too long because it requires (or might require) an ACPI function
call. This brings me again to: why bother and enable it in the first
place? Because this might not work from NMI context.
>From looking at #2. You remove put/get in console_write() and avoid
runtime PM by pm_runtime_get_noresume() and need the extra hook on
console exit. I wasn't aware that you can remove the console at runtime
(and assumed you have to stick to what said in console= at bootime).
Because if that is the case, you could simply strip UART_CAP_RPM and
then there is no more runtime-PM for you. Or is it too simple and I
miss something here?
> > In order to achieve the same thing you would have to disable the kernel
> > console on that UART. I leave this to Tony.
>
> Precisely the point of the series.
Sebastian
^ permalink raw reply
* Re: [PATCH v1 0/3] console, serial8250: Disable PM and DMA ops
From: Andy Shevchenko @ 2018-05-16 10:17 UTC (permalink / raw)
To: Sebastian Andrzej Siewior
Cc: Andy Shevchenko, Petr Mladek, Sergey Senozhatsky, Steven Rostedt,
Linux Kernel Mailing List, Greg Kroah-Hartman, Jiri Slaby,
open list:SERIAL DRIVERS, Arnd Bergmann, Tony Lindgren
In-Reply-To: <20180516100842.xuma7b3e727w7bpz@linutronix.de>
On Wed, May 16, 2018 at 1:08 PM, Sebastian Andrzej Siewior
<bigeasy@linutronix.de> wrote:
> On 2018-05-15 21:37:18 [+0300], Andy Shevchenko wrote:
>> On Tue, 2018-05-15 at 21:34 +0300, Andy Shevchenko wrote:
>> > Kernel console is sensitive to any kind of complex work needed to
>> > print
>> > out anything on it. One such case is emergency print during Oops.
>> >
>> > This series proposes to disable runtime PM and DMA operations on 8250
>> > serial console.
>> >
>> > More detailed explanation why is provided in patch 2.
>> >
>> > The series has been in our internal trees for years already with no
>> > problems observed.
>>
>> +Cc: Tony.
>>
>> You might have some thoughts / test means for this.
>
> I haven't look at the patches, just your cover letter. Disabling DMA on
> kernel-console should be fine.
Would you mind to give an Ack for it?
> The output is usually short so there
> shouldn't be much benefit from using it.
> I remember Tony wanted runtime-pm on the kernel console, too. And he
> told me explicit how to test it so that it works. Once the UART goes
> into PM (down), the whole IP block can go into power save mode. The
> board can be woken up by sending a character via the UART. The first few
> (incoming / read) characters are lost until the IP block is up again the
> frequency stable. This is known / expected.
Don't consider world the OMAP only. The things more complicated if we
go out of it. Which I tried to explain in the commit message of patch
2.
> In order to achieve the same thing you would have to disable the kernel
> console on that UART. I leave this to Tony.
Precisely the point of the series.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply
* Re: [PATCH v1 0/3] console, serial8250: Disable PM and DMA ops
From: Sebastian Andrzej Siewior @ 2018-05-16 10:08 UTC (permalink / raw)
To: Andy Shevchenko
Cc: Petr Mladek, Sergey Senozhatsky, Steven Rostedt, linux-kernel,
Greg Kroah-Hartman, Jiri Slaby, linux-serial, Arnd Bergmann,
Tony Lindgren
In-Reply-To: <ca78895ac7ac84ec1c7f2f33024237af329ffd7a.camel@linux.intel.com>
On 2018-05-15 21:37:18 [+0300], Andy Shevchenko wrote:
> On Tue, 2018-05-15 at 21:34 +0300, Andy Shevchenko wrote:
> > Kernel console is sensitive to any kind of complex work needed to
> > print
> > out anything on it. One such case is emergency print during Oops.
> >
> > This series proposes to disable runtime PM and DMA operations on 8250
> > serial console.
> >
> > More detailed explanation why is provided in patch 2.
> >
> > The series has been in our internal trees for years already with no
> > problems observed.
>
> +Cc: Tony.
>
> You might have some thoughts / test means for this.
I haven't look at the patches, just your cover letter. Disabling DMA on
kernel-console should be fine. The output is usually short so there
shouldn't be much benefit from using it.
I remember Tony wanted runtime-pm on the kernel console, too. And he
told me explicit how to test it so that it works. Once the UART goes
into PM (down), the whole IP block can go into power save mode. The
board can be woken up by sending a character via the UART. The first few
(incoming / read) characters are lost until the IP block is up again the
frequency stable. This is known / expected.
In order to achieve the same thing you would have to disable the kernel
console on that UART. I leave this to Tony.
Sebastian
^ permalink raw reply
* Re: [patch v21 1/4] drivers: jtag: Add JTAG core driver
From: Andy Shevchenko @ 2018-05-15 21:21 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, Jiri Pirko
In-Reply-To: <1526394095-5069-2-git-send-email-oleksandrs@mellanox.com>
On Tue, May 15, 2018 at 5:21 PM, Oleksandr Shamray
<oleksandrs@mellanox.com> wrote:
> 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
> 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>
Consider to preserve style (upper vs. lower).
> + 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: (Scan Data Register) Performs an IEEE 1149.1 Data Register scan
> + SIR: (Scan Instruction Register) Performs an IEEE 1149.1 Instruction
> + Register scan.
> + RUNTEST: Forces the IEEE 1149.1 bus to a run state for a specified
> + number of clocks or a specified time period.
Something feels wrong with formatting here.
> +#define MAX_JTAG_NAME_LEN (sizeof("jtag") + 5)
Interesting definition. Why not to set to 10 explicitly? And why 10?
(16 sounds better)
> +struct jtag {
> + struct miscdevice miscdev;
> + struct device *dev;
Doesn't miscdev parent contain exactly this one?
> + const struct jtag_ops *ops;
> + int id;
> + bool opened;
> + struct mutex open_lock;
> + unsigned long priv[0];
> +};
> + err = copy_to_user(u64_to_user_ptr(xfer.tdio),
> + (void *)(xfer_data), data_size);
Redundant parens in one case. Check the rest similar places.
> +static int jtag_open(struct inode *inode, struct file *file)
> +{
> + struct jtag *jtag = container_of(file->private_data, struct jtag,
> + miscdev);
I would don't care about length and put it on one line.
> + if (jtag->opened) {
> + jtag->opened = true;
> + jtag->opened = false;
Can it be opened non exclusively several times? If so, this needs to
be a ref counter instead.
> + if (!ops->idle || !ops->mode_set || !ops->status_get || !ops->xfer)
> + return NULL;
Are all of them mandatory?
> +int jtag_register(struct jtag *jtag)
Perhaps devm_ variant.
> +#define jtag_u64_to_ptr(arg) ((void *)(uintptr_t)arg)
Where is this used or supposed to be used?
> +#define JTAG_MAX_XFER_DATA_LEN 65535
Is this limitation from some spec?
Otherwise why not to allow 64K?
> +/**
> + * struct jtag_ops - callbacks for jtag control functions:
> + *
> + * @freq_get: get frequency function. Filled by device driver
> + * @freq_set: set frequency function. Filled by device driver
> + * @status_get: set status function. Filled by device driver
> + * @idle: set JTAG to idle state function. Filled by device driver
> + * @xfer: send JTAG xfer function. Filled by device driver
> + */
Perhaps you need to describe which of them are _really_ mandatory and
which are optional.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply
* Re: [patch v21 2/4] drivers: jtag: Add Aspeed SoC 24xx and 25xx families JTAG master driver
From: Andy Shevchenko @ 2018-05-15 21:00 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, Jiri Pirko
In-Reply-To: <1526394095-5069-3-git-send-email-oleksandrs@mellanox.com>
On Tue, May 15, 2018 at 5:21 PM, Oleksandr Shamray
<oleksandrs@mellanox.com> wrote:
> 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.
> +#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
> +#define ASPEED_JTAG_IOUT_LEN(len) (ASPEED_JTAG_CTL_ENG_EN |\
> + ASPEED_JTAG_CTL_ENG_OUT_EN |\
> + ASPEED_JTAG_CTL_INST_LEN(len))
Better to read
#define MY_COOL_CONST_OR_MACRO(xxx) \
...
> +#define ASPEED_JTAG_DOUT_LEN(len) (ASPEED_JTAG_CTL_ENG_EN |\
> + ASPEED_JTAG_CTL_ENG_OUT_EN |\
> + ASPEED_JTAG_CTL_DATA_LEN(len))
Ditto.
> +static char *end_status_str[] = {"idle", "ir pause", "drpause"};
> +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);
> + div = (apb_frq % freq == 0) ? (apb_frq / freq) - 1 : (apb_frq / freq);
Isn't it the same as
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 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);
Isn't it readsl() (or how it's called, I don't remember).
> +}
> +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);
In such cases I prefer to see a new line with a parameter in full.
Check all places.
> + aspeed_jtag->flag &= ~ASPEED_JTAG_ISR_INST_PAUSE;
> +}
> +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_test_idle_sw(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_idle_irpause[] = {1, 1, 0, 1, 0};
> + static const u8 sm_idle_drpause[] = {1, 0, 1, 0};
> + static const u8 sm_pause_idle[] = {1, 1, 0};
> + 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);
> + }
I would rather split this big switch to a few helper functions per
each status of surrounding switch.
> +
> + /* Stay on IDLE for at least TCK cycle */
> + for (i = 0; i < runtest->tck; i++)
> + aspeed_jtag_tck_cycle(aspeed_jtag, 0, 0);
> +}
> +/**
> + * aspeed_jtag_run_test_idle:
> + * JTAG reset: generates at least 9 TMS high and 1 TMS low to force
> + * devices into Run-Test/Idle State.
> + */
It's rather broken kernel doc.
> + aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_CTL_ENG_EN |
> + ASPEED_JTAG_CTL_ENG_OUT_EN |
> + ASPEED_JTAG_CTL_FORCE_TMS, ASPEED_JTAG_CTRL);
> + aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_EC_GO_IDLE,
> + ASPEED_JTAG_EC);
> + aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
> + ASPEED_JTAG_SW_MODE_TDIO, ASPEED_JTAG_SW);
Here you have permutations of flag some of which are repeatetive in
the code. Perhaps make additional definitions instead.
Check other similar places.
> + char tdo;
Indentation.
> + if (xfer->direction == JTAG_READ_XFER)
> + tdi = UINT_MAX;
> + else
> + tdi = data[index];
> + if (xfer->direction == JTAG_READ_XFER)
> + tdi = UINT_MAX;
> + else
> + tdi = data[index];
Take your time to think how the above duplication can be avoided.
> + }
> + }
> +
> + tdo = aspeed_jtag_tck_cycle(aspeed_jtag, 1, tdi & ASPEED_JTAG_DATA_MSB);
> + data[index] |= tdo << (shift_bits % ASPEED_JTAG_DATA_CHUNK_SIZE);
> +}
> + if (endstate != JTAG_STATE_IDLE) {
Why not to use positive check?
> + int i;
> +
> + for (i = 0; i <= xfer->length / BITS_PER_BYTE; i++) {
> + pos += snprintf(&dbg_str[pos], sizeof(dbg_str) - pos,
> + "0x%02x ", xfer_data[i]);
> + }
Oh, NO! Consider reading printk-formats (for %*ph) and other
documentation about available APIs.
> + if (!(aspeed_jtag->mode & JTAG_XFER_HW_MODE)) {
> + /* SW mode */
This is rather too complex to be in one function.
> + } else {
> + /* hw mode */
> + aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_SW);
> + aspeed_jtag_xfer_hw(aspeed_jtag, xfer, data);
For symmetry it might be another function.
> + }
> + dev_dbg(aspeed_jtag->dev, "status %x\n", status);
Perhaps someone should become familiar with tracepoints?
> + dev_err(aspeed_jtag->dev, "irq status:%x\n",
> + status);
Huh, really?! SPAM.
(I would drop it completely, though you may use ratelimited variant)
> + ret = IRQ_NONE;
> + }
> + return ret;
> +}
> + clk_prepare_enable(aspeed_jtag->pclk);
This might fail.
> + dev_dbg(&pdev->dev, "IRQ %d.\n", aspeed_jtag->irq);
Noise even for debug.
> + err = jtag_register(jtag);
Perhaps we might have devm_ variant of this. Check how SPI framework
deal with a such.
> +static int aspeed_jtag_remove(struct platform_device *pdev)
> +{
> + struct jtag *jtag;
> +
> + jtag = platform_get_drvdata(pdev);
Usually we put this on one line
> + aspeed_jtag_deinit(pdev, jtag_priv(jtag));
> + jtag_unregister(jtag);
> + jtag_free(jtag);
> + return 0;
> +}
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply
* Re: [PATCH v1 0/3] console, serial8250: Disable PM and DMA ops
From: Andy Shevchenko @ 2018-05-15 18:37 UTC (permalink / raw)
To: Petr Mladek, Sergey Senozhatsky, Steven Rostedt, linux-kernel,
Greg Kroah-Hartman, Jiri Slaby, linux-serial,
Sebastian Andrzej Siewior, Arnd Bergmann
Cc: Tony Lindgren
In-Reply-To: <20180515183409.78046-1-andriy.shevchenko@linux.intel.com>
On Tue, 2018-05-15 at 21:34 +0300, Andy Shevchenko wrote:
> Kernel console is sensitive to any kind of complex work needed to
> print
> out anything on it. One such case is emergency print during Oops.
>
> This series proposes to disable runtime PM and DMA operations on 8250
> serial console.
>
> More detailed explanation why is provided in patch 2.
>
> The series has been in our internal trees for years already with no
> problems observed.
+Cc: Tony.
You might have some thoughts / test means for this.
>
> Andy Shevchenko (3):
> console: introduce ->exit() callback
> serial: 8250_port: Don't use power management for kernel console
> serial: 8250_port: Disable DMA operations for kernel console
>
> drivers/tty/serial/8250/8250_core.c | 9 +++++++++
> drivers/tty/serial/8250/8250_port.c | 27 ++++++++++++++++++++++-----
> include/linux/console.h | 1 +
> include/linux/serial_8250.h | 1 +
> kernel/printk/printk.c | 3 +++
> 5 files changed, 36 insertions(+), 5 deletions(-)
>
--
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy
^ permalink raw reply
* [PATCH v1 3/3] serial: 8250_port: Disable DMA operations for kernel console
From: Andy Shevchenko @ 2018-05-15 18:34 UTC (permalink / raw)
To: Petr Mladek, Sergey Senozhatsky, Steven Rostedt, linux-kernel,
Greg Kroah-Hartman, Jiri Slaby, linux-serial,
Sebastian Andrzej Siewior, Arnd Bergmann
Cc: Andy Shevchenko
In-Reply-To: <20180515183409.78046-1-andriy.shevchenko@linux.intel.com>
It will be too tricky and error prone to allow DMA operations on kernel
console.
Disable any kind of DMA operations in such case.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/tty/serial/8250/8250_port.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index db97222a1bf4..9a4696ea728b 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -2371,7 +2371,10 @@ int serial8250_do_startup(struct uart_port *port)
* Request DMA channels for both RX and TX.
*/
if (up->dma) {
- retval = serial8250_request_dma(up);
+ if (uart_console(port))
+ retval = -ENXIO;
+ else
+ retval = serial8250_request_dma(up);
if (retval)
pr_warn_ratelimited("ttyS%d - failed to request DMA\n",
serial_index(port));
--
2.17.0
^ permalink raw reply related
* [PATCH v1 2/3] serial: 8250_port: Don't use power management for kernel console
From: Andy Shevchenko @ 2018-05-15 18:34 UTC (permalink / raw)
To: Petr Mladek, Sergey Senozhatsky, Steven Rostedt, linux-kernel,
Greg Kroah-Hartman, Jiri Slaby, linux-serial,
Sebastian Andrzej Siewior, Arnd Bergmann
Cc: Andy Shevchenko
In-Reply-To: <20180515183409.78046-1-andriy.shevchenko@linux.intel.com>
Doing any kind of power management for kernel console is really bad idea.
First of all, it runs in poll and atomic mode. This fact attaches a limitation
on the functions that might be called. For example, pm_runtime_get_sync() might
sleep and thus can't be used. On the other hand pm_runtime_get() doesn't
guarantee that device becomes powered on (fast enough). On ACPI enabled
platforms it might even call firmware for a job.
Besides that, imagine the case when console is about to print a kernel oops and
it's powered off. In such an emergency case calling the complex functions is
not the best what we can do, taking into consideration that user wants to see
at least something of the last kernel word before it passes away.
Here we modify the 8250 console code to prevent runtime power management.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/tty/serial/8250/8250_core.c | 9 +++++++++
drivers/tty/serial/8250/8250_port.c | 22 ++++++++++++++++++----
include/linux/serial_8250.h | 1 +
3 files changed, 28 insertions(+), 4 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 9342fc2ee7df..cdafee307482 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -612,6 +612,14 @@ static int univ8250_console_setup(struct console *co, char *options)
return retval;
}
+static void univ8250_console_exit(struct console *co)
+{
+ struct uart_port *port;
+
+ port = &serial8250_ports[co->index].port;
+ serial8250_console_exit(port);
+}
+
/**
* univ8250_console_match - non-standard console matching
* @co: registering console
@@ -670,6 +678,7 @@ static struct console univ8250_console = {
.write = univ8250_console_write,
.device = uart_console_device,
.setup = univ8250_console_setup,
+ .exit = univ8250_console_exit,
.match = univ8250_console_match,
.flags = CON_PRINTBUFFER | CON_ANYTIME,
.index = -1,
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 2ca7df29dc11..db97222a1bf4 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -3207,6 +3207,9 @@ static void serial8250_console_restore(struct uart_8250_port *up)
* any possible real use of the port...
*
* The console_lock must be held when we get here.
+ *
+ * Doing runtime PM is a really bad idea for the kernel console.
+ * Thus we assume that the function called when device is powered on.
*/
void serial8250_console_write(struct uart_8250_port *up, const char *s,
unsigned int count)
@@ -3218,8 +3221,6 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
touch_nmi_watchdog();
- serial8250_rpm_get(up);
-
if (port->sysrq)
locked = 0;
else if (oops_in_progress)
@@ -3264,7 +3265,6 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
if (locked)
spin_unlock_irqrestore(&port->lock, flags);
- serial8250_rpm_put(up);
}
static unsigned int probe_baud(struct uart_port *port)
@@ -3288,6 +3288,7 @@ int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
int bits = 8;
int parity = 'n';
int flow = 'n';
+ int ret;
if (!port->iobase && !port->membase)
return -ENODEV;
@@ -3297,7 +3298,20 @@ int serial8250_console_setup(struct uart_port *port, char *options, bool probe)
else if (probe)
baud = probe_baud(port);
- return uart_set_options(port, port->cons, baud, parity, bits, flow);
+ ret = uart_set_options(port, port->cons, baud, parity, bits, flow);
+ if (ret)
+ return ret;
+
+ if (port->dev)
+ pm_runtime_get_noresume(port->dev);
+
+ return 0;
+}
+
+void serial8250_console_exit(struct uart_port *port)
+{
+ if (port->dev)
+ pm_runtime_put_noidle(port->dev);
}
#endif /* CONFIG_SERIAL_8250_CONSOLE */
diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 76b9db71e489..f83309328b66 100644
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -171,6 +171,7 @@ void serial8250_set_defaults(struct uart_8250_port *up);
void serial8250_console_write(struct uart_8250_port *up, const char *s,
unsigned int count);
int serial8250_console_setup(struct uart_port *port, char *options, bool probe);
+void serial8250_console_exit(struct uart_port *port);
extern void serial8250_set_isa_configurator(void (*v)
(int port, struct uart_port *up,
--
2.17.0
^ permalink raw reply related
* [PATCH v1 1/3] console: introduce ->exit() callback
From: Andy Shevchenko @ 2018-05-15 18:34 UTC (permalink / raw)
To: Petr Mladek, Sergey Senozhatsky, Steven Rostedt, linux-kernel,
Greg Kroah-Hartman, Jiri Slaby, linux-serial,
Sebastian Andrzej Siewior, Arnd Bergmann
Cc: Andy Shevchenko
In-Reply-To: <20180515183409.78046-1-andriy.shevchenko@linux.intel.com>
Some consoles might require special operations on unregistering. For example,
serial console, when registered in the kernel, keeps power on for entire time,
until it gets unregistered. For such cases to have a balance we would provide
->exit() callback.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
include/linux/console.h | 1 +
kernel/printk/printk.c | 3 +++
2 files changed, 4 insertions(+)
diff --git a/include/linux/console.h b/include/linux/console.h
index dfd6b0e97855..62c5b958b548 100644
--- a/include/linux/console.h
+++ b/include/linux/console.h
@@ -147,6 +147,7 @@ struct console {
struct tty_driver *(*device)(struct console *, int *);
void (*unblank)(void);
int (*setup)(struct console *, char *);
+ void (*exit)(struct console *);
int (*match)(struct console *, char *name, int idx, char *options);
short flags;
short index;
diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 247808333ba4..a3170886f481 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -2756,6 +2756,9 @@ int unregister_console(struct console *console)
if (console_drivers != NULL && console->flags & CON_CONSDEV)
console_drivers->flags |= CON_CONSDEV;
+ if (console->exit)
+ console->exit(console);
+
console->flags &= ~CON_ENABLED;
console_unlock();
console_sysfs_notify();
--
2.17.0
^ permalink raw reply related
* [PATCH v1 0/3] console, serial8250: Disable PM and DMA ops
From: Andy Shevchenko @ 2018-05-15 18:34 UTC (permalink / raw)
To: Petr Mladek, Sergey Senozhatsky, Steven Rostedt, linux-kernel,
Greg Kroah-Hartman, Jiri Slaby, linux-serial,
Sebastian Andrzej Siewior, Arnd Bergmann
Cc: Andy Shevchenko
Kernel console is sensitive to any kind of complex work needed to print
out anything on it. One such case is emergency print during Oops.
This series proposes to disable runtime PM and DMA operations on 8250
serial console.
More detailed explanation why is provided in patch 2.
The series has been in our internal trees for years already with no
problems observed.
Andy Shevchenko (3):
console: introduce ->exit() callback
serial: 8250_port: Don't use power management for kernel console
serial: 8250_port: Disable DMA operations for kernel console
drivers/tty/serial/8250/8250_core.c | 9 +++++++++
drivers/tty/serial/8250/8250_port.c | 27 ++++++++++++++++++++++-----
include/linux/console.h | 1 +
include/linux/serial_8250.h | 1 +
kernel/printk/printk.c | 3 +++
5 files changed, 36 insertions(+), 5 deletions(-)
--
2.17.0
^ permalink raw reply
* [patch v21 4/4] Documentation: jtag: Add ABI documentation
From: Oleksandr Shamray @ 2018-05-15 14:21 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: <1526394095-5069-1-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>
---
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>
- 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 Kernel Version 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/jtag-dev | 27 +++++++++
Documentation/jtag/overview | 28 +++++++++
Documentation/jtag/transactions | 109 ++++++++++++++++++++++++++++++++++++
3 files changed, 164 insertions(+), 0 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/jtag-dev b/Documentation/ABI/testing/jtag-dev
new file mode 100644
index 0000000..4325316
--- /dev/null
+++ b/Documentation/ABI/testing/jtag-dev
@@ -0,0 +1,27 @@
+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)
+ The argument flag currently support only one access
+ mode O_RDWR.
+
+ ioctl(2)
+ Initiate various actions.
+ See the inline documentation in [include/uapi]<linux/jtag.h>
+ for descriptions of all ioctls.
+
+ close(2)
+ Stops and free up the I/O contexts that was associated
+ with the file descriptor.
+
+Users: TBD
diff --git a/Documentation/jtag/overview b/Documentation/jtag/overview
new file mode 100644
index 0000000..a86f188
--- /dev/null
+++ b/Documentation/jtag/overview
@@ -0,0 +1,28 @@
+Linux kernel JTAG support
+=========================
+
+The 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 hw specific driver
+User: close -> /dev/jatgX
diff --git a/Documentation/jtag/transactions b/Documentation/jtag/transactions
new file mode 100644
index 0000000..6a857c8
--- /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. Only one open operation per JTAG device
+can be performed. Two or more open for one device will return error
+
+Open/Close device:
+- open("/dev/jtag0", O_RDWR);
+- close(jtag_fd');
+
+ioctl()
+-------
+All access operations to JTAG devices performed through ioctl interface.
+The IOCTL interface supports this 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: 0 - run IDLE/PAUSE from current state
+ 1 - 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 len 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 hw 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);
--
1.7.1
^ permalink raw reply related
* [patch v21 3/4] Documentation: jtag: Add bindings for Aspeed SoC 24xx and 25xx families JTAG master driver
From: Oleksandr Shamray @ 2018-05-15 14:21 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,
Jiri Pirko
In-Reply-To: <1526394095-5069-1-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>
---
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 ++++++++++++++++++++
1 files changed, 22 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>;
+};
--
1.7.1
^ permalink raw reply related
* [patch v21 2/4] drivers: jtag: Add Aspeed SoC 24xx and 25xx families JTAG master driver
From: Oleksandr Shamray @ 2018-05-15 14:21 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,
Jiri Pirko
In-Reply-To: <1526394095-5069-1-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>
---
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 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 | 786 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 801 insertions(+), 0 deletions(-)
create mode 100644 drivers/jtag/jtag-aspeed.c
diff --git a/drivers/jtag/Kconfig b/drivers/jtag/Kconfig
index 43eb9a4..6b43ac8 100644
--- a/drivers/jtag/Kconfig
+++ b/drivers/jtag/Kconfig
@@ -16,3 +16,17 @@ 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..2d22de0
--- /dev/null
+++ b/drivers/jtag/jtag-aspeed.c
@@ -0,0 +1,786 @@
+// 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 <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_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);
+ div = (apb_frq % freq == 0) ? (apb_frq / freq) - 1 : (apb_frq / 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);
+
+ 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_test_idle_sw(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_idle_irpause[] = {1, 1, 0, 1, 0};
+ static const u8 sm_idle_drpause[] = {1, 0, 1, 0};
+ static const u8 sm_pause_idle[] = {1, 1, 0};
+ 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:
+ 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;
+ }
+ break;
+
+ case JTAG_STATE_PAUSEIR:
+ /* Fall-through */
+ case JTAG_STATE_PAUSEDR:
+ /* From IR/DR Pause */
+ 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;
+ }
+ 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);
+}
+
+/**
+ * aspeed_jtag_run_test_idle:
+ * JTAG reset: generates at least 9 TMS high and 1 TMS low to force
+ * devices into Run-Test/Idle State.
+ */
+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);
+
+ 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_MODE_EN |
+ ASPEED_JTAG_SW_MODE_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, unsigned long *data)
+{
+ unsigned long remain_xfer = xfer->length;
+ unsigned long shift_bits = 0;
+ unsigned long index = 0;
+ unsigned long tdi;
+ char tdo;
+
+ if (xfer->direction == JTAG_READ_XFER)
+ tdi = UINT_MAX;
+ else
+ tdi = 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) {
+ dev_dbg(aspeed_jtag->dev, "R/W data[%lu]:%lx\n",
+ index, data[index]);
+
+ tdo = 0;
+ index++;
+
+ if (xfer->direction == JTAG_READ_XFER)
+ tdi = UINT_MAX;
+ else
+ tdi = 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);
+}
+
+static void aspeed_jtag_xfer_push_data(struct aspeed_jtag *aspeed_jtag,
+ enum jtag_xfer_type type, u32 bits_len)
+{
+ dev_dbg(aspeed_jtag->dev, "shift bits %d\n", 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) {
+ dev_dbg(aspeed_jtag->dev, "IR Keep Pause\n");
+
+ 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 {
+ dev_dbg(aspeed_jtag->dev, "DR Keep Pause\n");
+ 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) {
+ dev_dbg(aspeed_jtag->dev, "IR go IDLE\n");
+
+ 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 {
+ dev_dbg(aspeed_jtag->dev, "DR go IDLE\n");
+
+ 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, unsigned long *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) {
+ dev_dbg(aspeed_jtag->dev, "W dr->dr_data[%lu]:%lx\n",
+ index, data[index]);
+
+ 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);
+ }
+ dev_dbg(aspeed_jtag->dev, "R dr->dr_data[%lu]:%lx\n",
+ index, data[index]);
+ }
+
+ remain_xfer = remain_xfer - shift_bits;
+ index++;
+ dev_dbg(aspeed_jtag->dev, "remain_xfer %lu\n", remain_xfer);
+ }
+}
+
+static int aspeed_jtag_xfer(struct jtag *jtag, struct jtag_xfer *xfer,
+ u8 *xfer_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};
+ struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
+ unsigned long *data = (unsigned long *)xfer_data;
+ unsigned long remain_xfer = xfer->length;
+ char dbg_str[256];
+ int pos = 0;
+ int i;
+
+ for (i = 0; i <= xfer->length / BITS_PER_BYTE; i++) {
+ pos += snprintf(&dbg_str[pos], sizeof(dbg_str) - pos,
+ "0x%02x ", xfer_data[i]);
+ }
+
+ dev_dbg(aspeed_jtag->dev, " %s %s xfer, mode:%s, END:%d, len:%lu, TDI[%s]\n",
+ xfer->type == JTAG_SIR_XFER ? "SIR" : "SDR",
+ xfer->direction == JTAG_READ_XFER ? "READ" : "WRITE",
+ aspeed_jtag->mode & JTAG_XFER_HW_MODE ? "HW" : "SW",
+ xfer->endstate, remain_xfer, dbg_str);
+
+ if (!(aspeed_jtag->mode & JTAG_XFER_HW_MODE)) {
+ /* SW mode */
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
+ ASPEED_JTAG_SW_MODE_TDIO, ASPEED_JTAG_SW);
+
+ 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));
+
+ aspeed_jtag_xfer_sw(aspeed_jtag, xfer, data);
+
+ /* 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));
+ }
+ } else {
+ /* hw mode */
+ aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_SW);
+ aspeed_jtag_xfer_hw(aspeed_jtag, xfer, data);
+ }
+
+ aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
+ ASPEED_JTAG_SW_MODE_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);
+ dev_dbg(aspeed_jtag->dev, "status %x\n", status);
+
+ 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;
+ }
+
+ clk_prepare_enable(aspeed_jtag->pclk);
+
+ aspeed_jtag->rst = devm_reset_control_get_shared(aspeed_jtag->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_MODE_EN |
+ ASPEED_JTAG_SW_MODE_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;
+ }
+ dev_dbg(&pdev->dev, "IRQ %d.\n", aspeed_jtag->irq);
+
+ 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 device *dev;
+ struct jtag *jtag;
+ int err;
+
+ dev = &pdev->dev;
+ jtag = jtag_alloc(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 = jtag_register(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;
+
+ jtag = platform_get_drvdata(pdev);
+ aspeed_jtag_deinit(pdev, jtag_priv(jtag));
+ jtag_unregister(jtag);
+ jtag_free(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 v21 1/4] drivers: jtag: Add JTAG core driver
From: Oleksandr Shamray @ 2018-05-15 14:21 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,
Jiri Pirko
In-Reply-To: <1526394095-5069-1-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>
---
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
Commen ts 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
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 only one open per JTAG port blocking with mutex blocking
v10->v11
Notifications from kbuild test robot <lkp@intel.com>
- include types.h headeri to jtag.h
- fix incompatible type of xfer callback
- remove rdundant class defination
- Fix return order in case of xfer error
V9->v10
Comments pointed by Greg KH <gregkh@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 | 10 ++
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/jtag/Kconfig | 18 +++
drivers/jtag/Makefile | 1 +
drivers/jtag/jtag.c | 274 ++++++++++++++++++++++++++++++++++
include/linux/jtag.h | 41 +++++
include/uapi/linux/jtag.h | 105 +++++++++++++
9 files changed, 454 insertions(+), 0 deletions(-)
create mode 100644 drivers/jtag/Kconfig
create mode 100644 drivers/jtag/Makefile
create mode 100644 drivers/jtag/jtag.c
create mode 100644 include/linux/jtag.h
create mode 100644 include/uapi/linux/jtag.h
diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index 7f7413e..c5548b5 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -318,6 +318,8 @@ Code Seq#(hex) Include File Comments
0xB0 all RATIO devices in development:
<mailto:vgo@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..2fd22d6 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7610,6 +7610,16 @@ 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/
+F: Documentation/devicetree/bindings/jtag/
+F: Documentation/ABI/testing/jtag-cdev
+
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-$(CONFIG_JTAG) += jtag/
diff --git a/drivers/jtag/Kconfig b/drivers/jtag/Kconfig
new file mode 100644
index 0000000..43eb9a4
--- /dev/null
+++ b/drivers/jtag/Kconfig
@@ -0,0 +1,18 @@
+menuconfig JTAG
+ tristate "JTAG support"
+ help
+ This provides basic core functionality support for JTAG class devices.
+ Hardware that is equipped with a JTAG microcontroller can be
+ supported by using this driver's interfaces.
+ This driver exposes a set of IOCTLs to the user space for
+ the following commands:
+ SDR: (Scan Data Register) Performs an IEEE 1149.1 Data Register scan
+ SIR: (Scan Instruction Register) Performs an IEEE 1149.1 Instruction
+ Register scan.
+ RUNTEST: Forces the IEEE 1149.1 bus to a run state for a specified
+ number of clocks or a specified time period.
+
+ If you want this support, you should say Y here.
+
+ To compile this driver as a module, choose M here: the module will
+ be called jtag.
diff --git a/drivers/jtag/Makefile b/drivers/jtag/Makefile
new file mode 100644
index 0000000..af37493
--- /dev/null
+++ b/drivers/jtag/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_JTAG) += jtag.o
diff --git a/drivers/jtag/jtag.c b/drivers/jtag/jtag.c
new file mode 100644
index 0000000..84c29c8
--- /dev/null
+++ b/drivers/jtag/jtag.c
@@ -0,0 +1,274 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// drivers/jtag/jtag.c
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@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>
+
+#define JTAG_NAME "jtag0"
+#define MAX_JTAG_NAME_LEN (sizeof("jtag") + 5)
+
+struct jtag {
+ struct miscdevice miscdev;
+ struct device *dev;
+ const struct jtag_ops *ops;
+ int id;
+ bool opened;
+ struct mutex open_lock;
+ unsigned long priv[0];
+};
+
+static DEFINE_IDA(jtag_ida);
+
+void *jtag_priv(struct jtag *jtag)
+{
+ return jtag->priv;
+}
+EXPORT_SYMBOL_GPL(jtag_priv);
+
+static long jtag_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct jtag *jtag = file->private_data;
+ struct jtag_run_test_idle idle;
+ struct jtag_xfer xfer;
+ u8 *xfer_data;
+ u32 data_size;
+ u32 value;
+ int err;
+
+ if (!arg)
+ return -EINVAL;
+
+ switch (cmd) {
+ case JTAG_GIOCFREQ:
+ if (!jtag->ops->freq_get)
+ return -EOPNOTSUPP;
+
+ err = jtag->ops->freq_get(jtag, &value);
+ if (err)
+ break;
+
+ if (put_user(value, (__u32 __user *)arg))
+ err = -EFAULT;
+ break;
+
+ case JTAG_SIOCFREQ:
+ if (!jtag->ops->freq_set)
+ return -EOPNOTSUPP;
+
+ if (get_user(value, (__u32 __user *)arg))
+ return -EFAULT;
+ if (value == 0)
+ return -EINVAL;
+
+ err = jtag->ops->freq_set(jtag, value);
+ break;
+
+ case JTAG_IOCRUNTEST:
+ if (copy_from_user(&idle, (const void __user *)arg,
+ sizeof(struct jtag_run_test_idle)))
+ return -EFAULT;
+
+ if (idle.endstate > JTAG_STATE_PAUSEDR)
+ return -EINVAL;
+
+ err = jtag->ops->idle(jtag, &idle);
+ break;
+
+ case JTAG_IOCXFER:
+ if (copy_from_user(&xfer, (const void __user *)arg,
+ sizeof(struct jtag_xfer)))
+ return -EFAULT;
+
+ if (xfer.length >= JTAG_MAX_XFER_DATA_LEN)
+ return -EINVAL;
+
+ if (xfer.type > JTAG_SDR_XFER)
+ return -EINVAL;
+
+ if (xfer.direction > JTAG_WRITE_XFER)
+ return -EINVAL;
+
+ if (xfer.endstate > JTAG_STATE_PAUSEDR)
+ return -EINVAL;
+
+ data_size = DIV_ROUND_UP(xfer.length, BITS_PER_BYTE);
+ xfer_data = memdup_user(u64_to_user_ptr(xfer.tdio), data_size);
+
+ if (IS_ERR(xfer_data))
+ return -EFAULT;
+
+ err = jtag->ops->xfer(jtag, &xfer, xfer_data);
+ if (err) {
+ kfree(xfer_data);
+ return -EFAULT;
+ }
+
+ err = copy_to_user(u64_to_user_ptr(xfer.tdio),
+ (void *)(xfer_data), data_size);
+ kfree(xfer_data);
+ if (err)
+ return -EFAULT;
+
+ if (copy_to_user((void __user *)arg, (void *)&xfer,
+ sizeof(struct jtag_xfer)))
+ return -EFAULT;
+ break;
+
+ case JTAG_GIOCSTATUS:
+ err = jtag->ops->status_get(jtag, &value);
+ if (err)
+ break;
+
+ err = put_user(value, (__u32 __user *)arg);
+ break;
+ case JTAG_SIOCMODE:
+ if (get_user(value, (__u32 __user *)arg))
+ return -EFAULT;
+ if (value == 0)
+ return -EINVAL;
+
+ err = jtag->ops->mode_set(jtag, value);
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ return err;
+}
+
+static int jtag_open(struct inode *inode, struct file *file)
+{
+ struct jtag *jtag = container_of(file->private_data, struct jtag,
+ miscdev);
+
+ if (mutex_lock_interruptible(&jtag->open_lock))
+ return -ERESTARTSYS;
+
+ if (jtag->opened) {
+ mutex_unlock(&jtag->open_lock);
+ return -EBUSY;
+ }
+ jtag->opened = true;
+ mutex_unlock(&jtag->open_lock);
+
+ nonseekable_open(inode, file);
+ file->private_data = jtag;
+ return 0;
+}
+
+static int jtag_release(struct inode *inode, struct file *file)
+{
+ struct jtag *jtag = file->private_data;
+
+ mutex_lock(&jtag->open_lock);
+ jtag->opened = false;
+ mutex_unlock(&jtag->open_lock);
+ return 0;
+}
+
+static const struct file_operations jtag_fops = {
+ .owner = THIS_MODULE,
+ .open = jtag_open,
+ .release = jtag_release,
+ .llseek = noop_llseek,
+ .unlocked_ioctl = jtag_ioctl,
+};
+
+struct jtag *jtag_alloc(size_t priv_size, const struct jtag_ops *ops)
+{
+ struct jtag *jtag;
+
+ if (!ops)
+ return NULL;
+
+ if (!ops->idle || !ops->mode_set || !ops->status_get || !ops->xfer)
+ return NULL;
+
+ jtag = kzalloc(sizeof(*jtag) + priv_size, GFP_KERNEL);
+ if (!jtag)
+ return NULL;
+
+ jtag->ops = ops;
+ return jtag;
+}
+EXPORT_SYMBOL_GPL(jtag_alloc);
+
+void jtag_free(struct jtag *jtag)
+{
+ kfree(jtag);
+}
+EXPORT_SYMBOL_GPL(jtag_free);
+
+int jtag_register(struct jtag *jtag)
+{
+ char *name;
+ int err;
+ int id;
+
+ id = ida_simple_get(&jtag_ida, 0, 0, GFP_KERNEL);
+ if (id < 0)
+ return id;
+
+ jtag->id = id;
+ jtag->opened = false;
+
+ name = kzalloc(MAX_JTAG_NAME_LEN, GFP_KERNEL);
+ if (!name) {
+ err = -ENOMEM;
+ goto err_jtag_alloc;
+ }
+
+ err = snprintf(name, MAX_JTAG_NAME_LEN, "jtag%d", id);
+ if (err < 0)
+ goto err_jtag_name;
+
+ mutex_init(&jtag->open_lock);
+ jtag->miscdev.fops = &jtag_fops;
+ jtag->miscdev.minor = MISC_DYNAMIC_MINOR;
+ jtag->miscdev.name = name;
+
+ err = misc_register(&jtag->miscdev);
+ if (err) {
+ dev_err(jtag->dev, "Unable to register device\n");
+ goto err_jtag_name;
+ }
+ return 0;
+
+err_jtag_name:
+ kfree(name);
+err_jtag_alloc:
+ ida_simple_remove(&jtag_ida, id);
+ return err;
+}
+EXPORT_SYMBOL_GPL(jtag_register);
+
+void jtag_unregister(struct jtag *jtag)
+{
+ misc_deregister(&jtag->miscdev);
+ kfree(jtag->miscdev.name);
+ ida_simple_remove(&jtag_ida, jtag->id);
+}
+EXPORT_SYMBOL_GPL(jtag_unregister);
+
+static void __exit jtag_exit(void)
+{
+ ida_destroy(&jtag_ida);
+}
+
+module_exit(jtag_exit);
+
+MODULE_AUTHOR("Oleksandr Shamray <oleksandrs@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..80a887f
--- /dev/null
+++ b/include/linux/jtag.h
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+// include/linux/jtag.h - JTAG class driver
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@mellanox.com>
+
+#ifndef __JTAG_H
+#define __JTAG_H
+
+#include <uapi/linux/jtag.h>
+
+#define jtag_u64_to_ptr(arg) ((void *)(uintptr_t)arg)
+
+#define JTAG_MAX_XFER_DATA_LEN 65535
+
+struct jtag;
+/**
+ * struct jtag_ops - callbacks for jtag control functions:
+ *
+ * @freq_get: get frequency function. Filled by device driver
+ * @freq_set: set frequency function. Filled by device driver
+ * @status_get: set status function. Filled by device driver
+ * @idle: set JTAG to idle state function. Filled by device driver
+ * @xfer: send JTAG xfer function. Filled by device driver
+ */
+struct jtag_ops {
+ int (*freq_get)(struct jtag *jtag, u32 *freq);
+ int (*freq_set)(struct jtag *jtag, u32 freq);
+ int (*status_get)(struct jtag *jtag, u32 *state);
+ int (*idle)(struct jtag *jtag, struct jtag_run_test_idle *idle);
+ int (*xfer)(struct jtag *jtag, struct jtag_xfer *xfer, u8 *xfer_data);
+ int (*mode_set)(struct jtag *jtag, u32 mode_mask);
+};
+
+void *jtag_priv(struct jtag *jtag);
+int jtag_register(struct jtag *jtag);
+void jtag_unregister(struct jtag *jtag);
+struct jtag *jtag_alloc(size_t priv_size, const struct jtag_ops *ops);
+void jtag_free(struct jtag *jtag);
+
+#endif /* __JTAG_H */
diff --git a/include/uapi/linux/jtag.h b/include/uapi/linux/jtag.h
new file mode 100644
index 0000000..ecd02a0
--- /dev/null
+++ b/include/uapi/linux/jtag.h
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0
+// include/uapi/linux/jtag.h - JTAG class driver uapi
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Oleksandr Shamray <oleksandrs@mellanox.com>
+
+#ifndef __UAPI_LINUX_JTAG_H
+#define __UAPI_LINUX_JTAG_H
+
+#include <linux/types.h>
+/*
+ * JTAG_XFER_HW_MODE: JTAG hardware mode. Used to set HW drived or bitbang
+ * mode. This is bitmask param of ioctl JTAG_SIOCMODE command
+ */
+#define JTAG_XFER_HW_MODE 1
+
+/**
+ * enum jtag_endstate:
+ *
+ * @JTAG_STATE_IDLE: JTAG state machine IDLE state
+ * @JTAG_STATE_PAUSEIR: JTAG state machine PAUSE_IR state
+ * @JTAG_STATE_PAUSEDR: JTAG state machine PAUSE_DR state
+ */
+enum jtag_endstate {
+ JTAG_STATE_IDLE,
+ JTAG_STATE_PAUSEIR,
+ JTAG_STATE_PAUSEDR,
+};
+
+/**
+ * enum jtag_xfer_type:
+ *
+ * @JTAG_SIR_XFER: SIR transfer
+ * @JTAG_SDR_XFER: SDR transfer
+ */
+enum jtag_xfer_type {
+ JTAG_SIR_XFER,
+ JTAG_SDR_XFER,
+};
+
+/**
+ * enum jtag_xfer_direction:
+ *
+ * @JTAG_READ_XFER: read transfer
+ * @JTAG_WRITE_XFER: write transfer
+ */
+enum jtag_xfer_direction {
+ JTAG_READ_XFER,
+ JTAG_WRITE_XFER,
+};
+
+/**
+ * struct jtag_run_test_idle - forces JTAG state machine to
+ * RUN_TEST/IDLE state
+ *
+ * @reset: 0 - run IDLE/PAUSE from current state
+ * 1 - go through TEST_LOGIC/RESET state before IDLE/PAUSE
+ * @end: completion flag
+ * @tck: clock counter
+ *
+ * Structure represents interface to JTAG device for jtag idle
+ * execution.
+ */
+struct jtag_run_test_idle {
+ __u8 reset;
+ __u8 endstate;
+ __u8 tck;
+};
+
+/**
+ * struct jtag_xfer - jtag xfer:
+ *
+ * @type: transfer type
+ * @direction: xfer direction
+ * @length: xfer bits len
+ * @tdio : xfer data array
+ * @endir: xfer end state
+ *
+ * Structure represents interface to JTAG device for jtag sdr xfer
+ * execution.
+ */
+struct jtag_xfer {
+ __u8 type;
+ __u8 direction;
+ __u8 endstate;
+ __u8 padding;
+ __u32 length;
+ __u64 tdio;
+};
+
+/* ioctl interface */
+#define __JTAG_IOCTL_MAGIC 0xb2
+
+#define JTAG_IOCRUNTEST _IOW(__JTAG_IOCTL_MAGIC, 0,\
+ struct jtag_run_test_idle)
+#define JTAG_SIOCFREQ _IOW(__JTAG_IOCTL_MAGIC, 1, unsigned int)
+#define JTAG_GIOCFREQ _IOR(__JTAG_IOCTL_MAGIC, 2, unsigned int)
+#define JTAG_IOCXFER _IOWR(__JTAG_IOCTL_MAGIC, 3, struct jtag_xfer)
+#define JTAG_GIOCSTATUS _IOWR(__JTAG_IOCTL_MAGIC, 4, enum jtag_endstate)
+#define JTAG_SIOCMODE _IOW(__JTAG_IOCTL_MAGIC, 5, unsigned int)
+
+#define JTAG_FIRST_MINOR 0
+#define JTAG_MAX_DEVICES 32
+
+#endif /* __UAPI_LINUX_JTAG_H */
--
1.7.1
^ permalink raw reply related
* [patch v21 0/4] JTAG driver introduction
From: Oleksandr Shamray @ 2018-05-15 14:21 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
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/jtag-dev | 27 +
.../devicetree/bindings/jtag/aspeed-jtag.txt | 22 +
Documentation/ioctl/ioctl-number.txt | 2 +
Documentation/jtag/overview | 28 +
Documentation/jtag/transactions | 109 +++
MAINTAINERS | 10 +
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/jtag/Kconfig | 32 +
drivers/jtag/Makefile | 2 +
drivers/jtag/jtag-aspeed.c | 786 ++++++++++++++++++++
drivers/jtag/jtag.c | 274 +++++++
include/linux/jtag.h | 41 +
include/uapi/linux/jtag.h | 105 +++
14 files changed, 1441 insertions(+), 0 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
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