The Aspeed Watchdog and Timer models have a link pointing to the SCU
controller model of the machine.
Change the "scu" property definition so that it explicitly sets the
pointer. The property isn't optional : not being able to set the link
is a bug and QEMU should rather abort than exit in this case.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20191119141211.25716-17-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The AST2600 timer replaces control register 2 with a interrupt status
register. It is set by hardware when an IRQ occurs and cleared by
software.
Modify the vmstate version to take into account the new fields.
Based on previous work from Joel Stanley.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Message-id: 20190925143248.10000-8-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The AST2600 timer has a third control register that is used to
implement a set-to-clear feature for the main control register.
On the AST2600, it is not configurable via 0x38 (control register 3)
as it is on the AST2500.
Based on previous work from Joel Stanley.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Message-id: 20190925143248.10000-7-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The AST2500 timer has a third control register that is used to
implement a set-to-clear feature for the main control register.
This models the behaviour expected by the AST2500 while maintaining
the same behaviour for the AST2400.
The vmstate version is not increased yet because the structure is
modified again in the following patches.
Based on previous work from Joel Stanley.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Message-id: 20190925143248.10000-6-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The most important changes will be on the register range 0x34 - 0x3C
memops. Introduce class read/write operations to handle the
differences between SoCs.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Message-id: 20190925143248.10000-5-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The APB frequency can be calculated directly when needed from the
HPLL_PARAM and CLK_SEL register values. This removes useless state in
the model.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20190904070506.1052-11-clg@kaod.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
First up: This is not the way the hardware behaves.
However, it helps resolve real-world problems with short periods being
used under Linux. Commit 4451d3f59f2a ("clocksource/drivers/fttmr010:
Fix set_next_event handler") in Linux fixed the timer driver to
correctly schedule the next event for the Aspeed controller, and in
combination with 5daa8212c08e ("ARM: dts: aspeed: Describe random number
device") Linux will now set a timer with a period as low as 1us.
Configuring a qemu timer with such a short period results in spending
time handling the interrupt in the model rather than executing guest
code, leading to noticeable "sticky" behaviour in the guest.
The behaviour of Linux is correct with respect to the hardware, so we
need to improve our handling under emulation. The approach chosen is to
provide back-pressure information by calculating an acceptable minimum
number of ticks to be set on the model. Under Linux an additional read
is added in the timer configuration path to detect back-pressure, which
will never occur on hardware. However if back-pressure is observed, the
driver alerts the clock event subsystem, which then performs its own
next event dilation via a config option - d1748302f70b ("clockevents:
Make minimum delay adjustments configurable")
A minimum period of 5us was experimentally determined on a Lenovo
T480s, which I've increased to 20us for "safety".
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20190704055150.4899-1-clg@kaod.org
[clg: - changed the computation of min_ticks to be done each time the
timer value is reloaded. It removes the ordering issue of the
timer and scu reset handlers but is slightly slower ]
- introduced TIMER_MIN_NS
- introduced calculate_min_ticks() ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In my "build everything" tree, changing migration/vmstate.h triggers a
recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).
hw/hw.h supposedly includes it for convenience. Several other headers
include it just to get VMStateDescription. The previous commit made
that unnecessary.
Include migration/vmstate.h only where it's still needed. Touching it
now recompiles only some 1600 objects.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-16-armbru@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
In my "build everything" tree, changing hw/irq.h triggers a recompile
of some 5400 out of 6600 objects (not counting tests and objects that
don't depend on qemu/osdep.h).
hw/hw.h supposedly includes it for convenience. Several other headers
include it just to get qemu_irq and.or qemu_irq_handler.
Move the qemu_irq and qemu_irq_handler typedefs from hw/irq.h to
qemu/typedefs.h, and then include hw/irq.h only where it's still
needed. Touching it now recompiles only some 500 objects.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-13-armbru@redhat.com>
If the host decrements the counter register that results in a negative
delta. This is then passed to muldiv64 which only handles unsigned
numbers resulting in bogus results.
This fix ensures the delta being operated on is positive.
Test case: kexec a kernel using aspeed_timer and it will freeze on the
second bootup when the kernel initializes the timer. With this patch
that no longer happens and the timer appears to run OK.
Signed-off-by: Christian Svensson <bluecmd@google.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Message-id: 20190618165311.27066-12-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
If the match value exceeds reload then we don't want to include it in
calculations for the next event.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20190618165311.27066-10-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
From the datasheet:
This register stores the current status of counter #N. When timer
enable bit TMC30[N * b] is disabled, the reload register will be
loaded into this counter. When timer bit TMC30[N * b] is set, the
counter will start to decrement. CPU can update this register value
when enable bit is set.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Message-id: 20190618165311.27066-9-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The Linux kernel driver was updated in commit 4451d3f59f2a
("clocksource/drivers/fttmr010: Fix set_next_event handler) to fix an
issue observed on hardware:
> RELOAD register is loaded into COUNT register when the aspeed timer
> is enabled, which means the next event may be delayed because timer
> interrupt won't be generated until <0xFFFFFFFF - current_count +
> cycles>.
When running under Qemu, the system appeared "laggy". The guest is now
scheduling timer events too regularly, starving the host of CPU time.
This patch modifies the timer model to attempt to schedule the timer
expiry as the guest requests, but if we have missed the deadline we
re interrupt and try again, which allows the guest to catch up.
Provides expected behaviour with old and new guest code.
Fixes: c04bd47db6 ("hw/timer: Add ASPEED timer device model")
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20190618165311.27066-8-clg@kaod.org
[clg: - merged a fix from Andrew Jeffery <andrew@aj.id.au>
"Fire interrupt on failure to meet deadline"
https://lists.ozlabs.org/pipermail/openbmc/2019-January/014641.html
- adapted commit log
- checkpatch fixes ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
From include/qapi/error.h:
* Pass an existing error to the caller with the message modified:
* error_propagate(errp, err);
* error_prepend(errp, "Could not frobnicate '%s': ", name);
Fei Li pointed out that doing error_propagate() first doesn't work
well when @errp is &error_fatal or &error_abort: the error_prepend()
is never reached.
Since I doubt fixing the documentation will stop people from getting
it wrong, introduce error_propagate_prepend(), in the hope that it
lures people away from using its constituents in the wrong order.
Update the instructions in error.h accordingly.
Convert existing error_prepend() next to error_propagate to
error_propagate_prepend(). If any of these get reached with
&error_fatal or &error_abort, the error messages improve. I didn't
check whether that's the case anywhere.
Cc: Fei Li <fli@suse.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20181017082702.5581-2-armbru@redhat.com>
In file included from /home/thuth/devel/qemu/hw/timer/aspeed_timer.c:16:
/home/thuth/devel/qemu/include/hw/misc/aspeed_scu.h:37:3: error:
redefinition of typedef 'AspeedSCUState' is a C11 feature
[-Werror,-Wtypedef-redefinition]
} AspeedSCUState;
^
/home/thuth/devel/qemu/include/hw/timer/aspeed_timer.h:27:31: note:
previous definition is here
typedef struct AspeedSCUState AspeedSCUState;
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180921161939.822-2-clg@kaod.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The timer controller can be driven by either an external 1MHz clock or
by the APB clock. Today, the model makes the assumption that the APB
frequency is always set to 24MHz but this is incorrect.
The AST2400 SoC on the palmetto machines uses a 48MHz input clock
source and the APB can be set to 48MHz. The consequence is a general
system slowdown. The QEMU machines using the AST2500 SoC do not seem
impacted today because the APB frequency is still set to 24MHz.
We fix the timer frequency for all SoCs by linking the Timer model to
the SCU model. The APB frequency driving the timers is now the one
configured for the SoC.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Message-id: 20180622075700.5923-4-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
commit 1d3e65aa7a ("hw/timer: Add value matching support to
aspeed_timer") increased the vmstate version of aspeed.timer because
the state had changed, but it also bumped the version of the
VMSTATE_STRUCT_ARRAY under the aspeed.timerctrl which did not need to.
Change back this version to fix migration.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20180423101433.17759-1-clg@kaod.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When a timer is enabled before a reload value is set, the controller
waits for a reload value to be set before starting decrementing. This
fix tries to cover that case by changing the timer expiry only when
a reload value is valid.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Message-id: 1496739312-32304-1-git-send-email-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Value matching allows Linux to boot with CONFIG_NO_HZ_IDLE=y on the
palmetto-bmc machine. Two match registers are provided for each timer.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Message-id: 1465974248-20434-1-git-send-email-andrew@aj.id.au
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This is not visible with the default "log" trace backend. With other
backends however trace.h does not include qemu/log.h, resulting in
build failures.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1463745452-25831-2-git-send-email-pbonzini@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Implement basic ASPEED timer functionality for the AST2400 SoC[1]: Up to
8 timers can independently be configured, enabled, reset and disabled.
Some hardware features are not implemented, namely clock value matching
and pulse generation, but the implementation is enough to boot the Linux
kernel configured with aspeed_defconfig.
[1] http://www.aspeedtech.com/products.php?fPath=20&rId=376
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Message-id: 1458096317-25223-2-git-send-email-andrew@aj.id.au
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
