Commit graph

30 commits

Author SHA1 Message Date
Marc Zyngier
046a6ee234 irqchip: Bulk conversion to generic_handle_domain_irq()
Wherever possible, replace constructs that match either
generic_handle_irq(irq_find_mapping()) or
generic_handle_irq(irq_linear_revmap()) to a single call to
generic_handle_domain_irq().

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:19 +01:00
Jisheng Zhang
e03b7c1bcb irqchip/sifive-plic: Mark two global variables __ro_after_init
All of these two are never modified after init, so they can be
 __ro_after_init.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210330020911.26423e9e@xhacker
2021-04-07 13:25:52 +01:00
Greentime Hu
f9ac7bbd6e irqchip/sifive-plic: Fix chip_data access within a hierarchy
The plic driver crashes in plic_irq_unmask() when the interrupt is within a
hierarchy, as it picks the top-level chip_data instead of its local one.

Using irq_data_get_irq_chip_data() instead of irq_get_chip_data() solves
the issue for good.

Fixes: f1ad1133b1 ("irqchip/sifive-plic: Add support for multiple PLICs")
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
[maz: rewrote commit message]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Link: https://lore.kernel.org/r/20201029023738.127472-1-greentime.hu@sifive.com
2020-11-01 11:52:27 +00:00
Greentime Hu
a7480c5d72 irqchip/sifive-plic: Fix broken irq_set_affinity() callback
An interrupt submitted to an affinity change will always be left enabled
after plic_set_affinity() has been called, while the expectation is that
it should stay in whatever state it was before the call.

Preserving the configuration fixes a PWM hang issue on the Unleashed
board.

[  919.015783] rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
[  919.020922] rcu:     0-...0: (0 ticks this GP)
idle=7d2/1/0x4000000000000002 softirq=1424/1424 fqs=105807
[  919.030295]  (detected by 1, t=225825 jiffies, g=1561, q=3496)
[  919.036109] Task dump for CPU 0:
[  919.039321] kworker/0:1     R  running task        0    30      2 0x00000008
[  919.046359] Workqueue: events set_brightness_delayed
[  919.051302] Call Trace:
[  919.053738] [<ffffffe000930d92>] __schedule+0x194/0x4de
[  982.035783] rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
[  982.040923] rcu:     0-...0: (0 ticks this GP)
idle=7d2/1/0x4000000000000002 softirq=1424/1424 fqs=113325
[  982.050294]  (detected by 1, t=241580 jiffies, g=1561, q=3509)
[  982.056108] Task dump for CPU 0:
[  982.059321] kworker/0:1     R  running task        0    30      2 0x00000008
[  982.066359] Workqueue: events set_brightness_delayed
[  982.071302] Call Trace:
[  982.073739] [<ffffffe000930d92>] __schedule+0x194/0x4de
[..]

Fixes: bb0fed1c60 ("irqchip/sifive-plic: Switch to fasteoi flow")
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
[maz: tidy-up commit message]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20201020081532.2377-1-greentime.hu@sifive.com
2020-10-25 12:33:07 +00:00
Anup Patel
6b7ce8927b
irqchip: RISC-V per-HART local interrupt controller driver
The RISC-V per-HART local interrupt controller manages software
interrupts, timer interrupts, external interrupts (which are routed
via the platform level interrupt controller) and other per-HART
local interrupts.

We add a driver for the RISC-V local interrupt controller, which
eventually replaces the RISC-V architecture code, allowing for a
better split between arch code and drivers.

The driver is compliant with RISC-V Hart-Level Interrupt Controller
DT bindings located at:
Documentation/devicetree/bindings/interrupt-controller/riscv,cpu-intc.txt

Co-developed-by: Palmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: Anup Patel <anup.patel@wdc.com>
[Palmer: Cleaned up warnings]
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2020-06-09 19:11:21 -07:00
Anup Patel
d175d699df
RISC-V: Rename and move plic_find_hart_id() to arch directory
The plic_find_hart_id() can be useful to other interrupt controller
drivers (such as RISC-V local interrupt driver) so we rename this
function to riscv_of_parent_hartid() and place it in arch directory
along with riscv_of_processor_hartid().

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-06-09 19:11:20 -07:00
Anup Patel
0e375f5101 irqchip/sifive-plic: Improve boot prints for multiple PLIC instances
We improve PLIC banner to help distinguish multiple PLIC instances
in boot time prints.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Link: https://lore.kernel.org/r/20200518091441.94843-4-anup.patel@wdc.com
2020-05-25 10:38:25 +01:00
Anup Patel
2234ae846c irqchip/sifive-plic: Setup cpuhp once after boot CPU handler is present
For multiple PLIC instances, the plic_init() is called once for each
PLIC instance. Due to this we have two issues:
1. cpuhp_setup_state() is called multiple times
2. plic_starting_cpu() can crash for boot CPU if cpuhp_setup_state()
   is called before boot CPU PLIC handler is available.

Address both issues by only initializing the HP notifiers when
the boot CPU setup is complete.

Fixes: f1ad1133b1 ("irqchip/sifive-plic: Add support for multiple PLICs")
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200518091441.94843-3-anup.patel@wdc.com
2020-05-25 10:36:53 +01:00
Anup Patel
2458ed31e9 irqchip/sifive-plic: Set default irq affinity in plic_irqdomain_map()
For multiple PLIC instances, each PLIC can only target a subset of
CPUs which is represented by "lmask" in the "struct plic_priv".

Currently, the default irq affinity for each PLIC interrupt is all
online CPUs which is illegal value for default irq affinity when we
have multiple PLIC instances. To fix this, we now set "lmask" as the
default irq affinity in for each interrupt in plic_irqdomain_map().

Fixes: f1ad1133b1 ("irqchip/sifive-plic: Add support for multiple PLICs")
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200518091441.94843-2-anup.patel@wdc.com
2020-05-25 10:36:09 +01:00
Wesley W. Terpstra
82f2202ddc irqchip/sifive-plic: Remove incorrect requirement about number of irq contexts
A PLIC may not be connected to all the cores. In that case, nr_contexts
may be less than num_possible_cpus. This requirement is only valid a single
PLIC is the only interrupt controller for the whole system.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: "Wesley W. Terpstra" <wesley@sifive.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Link: https://lore.kernel.org/r/20200512172636.96299-1-atish.patra@wdc.com

[Atish: Modified the commit text]
2020-05-18 10:28:30 +01:00
Atish Patra
d727be7bbf irqchip/sifive-plic: Fix maximum priority threshold value
As per the PLIC specification, maximum priority threshold value is 0x7
not 0xF. Even though it doesn't cause any error in qemu/hifive unleashed,
there may be some implementation which checks the upper bound resulting in
an illegal access.

Fixes: ccbe80bad5 ("irqchip/sifive-plic: Enable/Disable external interrupts upon cpu online/offline")
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200403014609.71831-1-atish.patra@wdc.com
2020-04-17 08:59:28 +01:00
Atish Patra
f1ad1133b1 irqchip/sifive-plic: Add support for multiple PLICs
Current, PLIC driver can support only 1 PLIC on the board. However,
there can be multiple PLICs present on a two socket systems in RISC-V.

Modify the driver so that each PLIC handler can have a information
about individual PLIC registers and an irqdomain associated with it.

Tested on two socket RISC-V system based on VCU118 FPGA connected via
OmniXtend protocol.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20200302231146.15530-3-atish.patra@wdc.com
2020-03-16 15:48:54 +00:00
Atish Patra
ccbe80bad5 irqchip/sifive-plic: Enable/Disable external interrupts upon cpu online/offline
Currently, PLIC threshold is only initialized once in the beginning.
However, threshold can be set to disabled if a CPU is marked offline with
CPU hotplug feature. This will not allow to change the irq affinity to a
CPU that just came online.

Add PLIC specific CPU hotplug callbacks and enable the threshold when a CPU
comes online. Take this opportunity to move the external interrupt enable
code from trap init to PLIC driver as well. On cpu offline path, the driver
performs the exact opposite operations i.e. disable the interrupt and
the threshold.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20200302231146.15530-2-atish.patra@wdc.com
2020-03-16 15:48:54 +00:00
Thomas Gleixner
43ee74487b irqchip updates for Linux 5.6:
- Conversion of the SiFive PLIC to hierarchical domains
 - New SiFive GPIO irqchip driver
 - New Aspeed SCI irqchip driver
 - New NXP INTMUX irqchip driver
 - Additional support for the Meson A1 GPIO irqchip
 - First part of the GICv4.1 support
 - Assorted fixes
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Merge tag 'irqchip-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core

Pull irqchip updates from Marc Zyngier:

- Conversion of the SiFive PLIC to hierarchical domains
- New SiFive GPIO irqchip driver
- New Aspeed SCI irqchip driver
- New NXP INTMUX irqchip driver
- Additional support for the Meson A1 GPIO irqchip
- First part of the GICv4.1 support
- Assorted fixes
2020-01-24 20:08:51 +01:00
Yash Shah
466008f984 irqchip/sifive-plic: Support irq domain hierarchy
Add support for hierarchical irq domains. This is needed as
pre-requisite for gpio-sifive driver.

Signed-off-by: Yash Shah <yash.shah@sifive.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1575976274-13487-4-git-send-email-yash.shah@sifive.com
2020-01-20 09:24:56 +00:00
Paul Walmsley
2f3035da40 riscv: prefix IRQ_ macro names with an RV_ namespace
"IRQ_TIMER", used in the arch/riscv CSR header file, is a sufficiently
generic macro name that it's used by several source files across the
Linux code base.  Some of these other files ultimately include the
arch/riscv CSR include file, causing collisions.  Fix by prefixing the
RISC-V csr.h IRQ_ macro names with an RV_ prefix.

Fixes: a4c3733d32 ("riscv: abstract out CSR names for supervisor vs machine mode")
Reported-by: Olof Johansson <olof@lixom.net>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2020-01-04 21:48:59 -08:00
Christoph Hellwig
a4c3733d32 riscv: abstract out CSR names for supervisor vs machine mode
Many of the privileged CSRs exist in a supervisor and machine version
that are used very similarly.  Provide versions of the CSR names and
fields that map to either the S-mode or M-mode variant depending on
a new CONFIG_RISCV_M_MODE kconfig symbol.

Contains contributions from Damien Le Moal <Damien.LeMoal@wdc.com>
and Paul Walmsley <paul.walmsley@sifive.com>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de> # for drivers/clocksource, drivers/irqchip
[paul.walmsley@sifive.com: updated to apply]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-11-05 09:20:42 -08:00
Thomas Gleixner
1486b7b42b irqchip updates for 5.4, take 2
- Sifive PLIC: force driver to skip non-relevant contexts
 - GICv4: Don't send VMOVP commands to ITSs that don't have
   this vPE mapped
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Merge tag 'irqchip-fixes-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent

Pull the second lot of irqchip updates for 5.4 from Marc Zyngier:

- Sifive PLIC: force driver to skip non-relevant contexts
- GICv4: Don't send VMOVP commands to ITSs that don't have
  this vPE mapped
2019-10-25 14:25:15 +02:00
Alan Mikhak
41860cc447 irqchip/sifive-plic: Skip contexts except supervisor in plic_init()
Modify plic_init() to skip .dts interrupt contexts other
than supervisor external interrupt.

The .dts entry for plic may specify multiple interrupt contexts.
For example, it may assign two entries IRQ_M_EXT and IRQ_S_EXT,
in that order, to the same interrupt controller. This patch
modifies plic_init() to skip the IRQ_M_EXT context since
IRQ_S_EXT is currently the only supported context.

If IRQ_M_EXT is not skipped, plic_init() will report "handler
already present for context" when it comes across the IRQ_S_EXT
context in the next iteration of its loop.

Without this patch, .dts would have to be edited to replace the
value of IRQ_M_EXT with -1 for it to be skipped.

Signed-off-by: Alan Mikhak <alan.mikhak@sifive.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Paul Walmsley <paul.walmsley@sifive.com> # arch/riscv
Link: https://lkml.kernel.org/r/1571933503-21504-1-git-send-email-alan.mikhak@sifive.com
2019-10-25 11:48:13 +01:00
Thomas Gleixner
c9b59181c2 irqchip fixes for 5.4, take #1
- Add retrigger support to Amazon's al-fic driver
 - Add SAM9X60 support to Atmel's AIC5 irqchip
 - Fix GICv3 maximum interrupt calculation
 - Convert SiFive's PLIC to the fasteoi IRQ flow
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Merge tag 'irqchip-fixes-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent

Pull irqchip fixes from Marc Zyngier:

 - Add retrigger support to Amazon's al-fic driver
 - Add SAM9X60 support to Atmel's AIC5 irqchip
 - Fix GICv3 maximum interrupt calculation
 - Convert SiFive's PLIC to the fasteoi IRQ flow
2019-10-14 20:35:58 +02:00
Marc Zyngier
bb0fed1c60 irqchip/sifive-plic: Switch to fasteoi flow
The SiFive PLIC interrupt controller seems to have all the HW
features to support the fasteoi flow, but the driver seems to be
stuck in a distant past. Bring it into the 21st century.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Palmer Dabbelt <palmer@sifive.com> (QEMU Boot)
Tested-by: Darius Rad <darius@bluespec.com> (on 2 HW PLIC implementations)
Tested-by: Paul Walmsley <paul.walmsley@sifive.com> (HiFive Unleashed)
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/8636gxskmj.wl-maz@kernel.org
2019-09-18 12:29:52 +01:00
Christoph Hellwig
9ce06497c2 irqchip/sifive-plic: set max threshold for ignored handlers
When running in M-mode, the S-mode plic handlers are still listed in the
device tree.  Ignore them by setting the maximum threshold.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-09-05 01:59:55 -07:00
Anup Patel
cc9f04f9a8 irqchip/sifive-plic: Implement irq_set_affinity() for SMP host
Currently on SMP host, all CPUs take external interrupts routed via
PLIC. All CPUs will try to claim a given external interrupt but only
one of them will succeed while other CPUs would simply resume whatever
they were doing before. This means if we have N CPUs then for every
external interrupt N-1 CPUs will always fail to claim it and waste
their CPU time.

Instead of above, external interrupts should be taken by only one CPU
and we should have provision to explicitly specify IRQ affinity from
kernel-space or user-space.

This patch provides irq_set_affinity() implementation for PLIC driver.
It also updates irq_enable() such that PLIC interrupts are only enabled
for one of CPUs specified in IRQ affinity mask.

With this patch in-place, we can change IRQ affinity at any-time from
user-space using procfs.

Example:

/ # cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
  8:         44          0          0          0  SiFive PLIC   8  virtio0
 10:         48          0          0          0  SiFive PLIC  10  ttyS0
IPI0:        55        663         58        363  Rescheduling interrupts
IPI1:         0          1          3         16  Function call interrupts
/ #
/ #
/ # echo 4 > /proc/irq/10/smp_affinity
/ #
/ # cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
  8:         45          0          0          0  SiFive PLIC   8  virtio0
 10:        160          0         17          0  SiFive PLIC  10  ttyS0
IPI0:        68        693         77        410  Rescheduling interrupts
IPI1:         0          2          3         16  Function call interrupts

Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-21 10:32:21 +00:00
Anup Patel
6adfe8d2f5 irqchip/sifive-plic: Differentiate between PLIC handler and context
We explicitly differentiate between PLIC handler and context because
PLIC context is for given mode of HART whereas PLIC handler is per-CPU
software construct meant for handling interrupts from a particular
PLIC context.

To achieve this differentiation, we rename "nr_handlers" to "nr_contexts"
and "nr_mapped" to "nr_handlers" in plic_init().

Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-21 10:32:17 +00:00
Anup Patel
3fecb5aac2 irqchip/sifive-plic: Add warning in plic_init() if handler already present
We have two enteries (one for M-mode and another for S-mode) in the
interrupts-extended DT property of PLIC DT node for each HART. It is
expected that firmware/bootloader will set M-mode HWIRQ line of each
HART to 0xffffffff (i.e. -1) in interrupts-extended DT property
because Linux runs in S-mode only.

If firmware/bootloader is buggy then it will not correctly update
interrupts-extended DT property which might result in a plic_handler
configured twice. This patch adds a warning in plic_init() if a
plic_handler is already marked present. This warning provides us
a hint about incorrectly updated interrupts-extended DT property.

Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-21 10:32:12 +00:00
Anup Patel
86c7cbf1e8 irqchip/sifive-plic: Pre-compute context hart base and enable base
This patch does following optimizations:
1. Pre-compute hart base for each context handler
2. Pre-compute enable base for each context handler
3. Have enable lock for each context handler instead
of global plic_toggle_lock

Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-21 10:32:05 +00:00
Atish Patra
fc03acaeab irqchip/irq-sifive-plic: Check and continue in case of an invalid cpuid.
riscv_hartid_to_cpuid can return invalid cpuid for a hart that is
present in DT but was never brought up.

Print the appropriate warning message and continue.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-14 12:24:34 +00:00
Atish Patra
f99fb607fb
RISC-V: Use Linux logical CPU number instead of hartid
Setup the cpu_logical_map during boot. Moreover, every SBI call
and PLIC context are based on the physical hartid. Use the logical
CPU to hartid mapping to pass correct hartid to respective functions.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22 17:03:37 -07:00
Palmer Dabbelt
b2f8cfa7ac
RISC-V: Rename riscv_of_processor_hart to riscv_of_processor_hartid
It's a bit confusing exactly what this function does: it actually
returns the hartid of an OF processor node, failing with -1 on invalid
nodes.  I've changed the name to _hartid() in order to make that a bit
more clear, as well as adding a comment.

Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
[Atish: code comment formatting update]
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22 17:03:36 -07:00
Christoph Hellwig
8237f8bc4f
irqchip: add a SiFive PLIC driver
Add a driver for the SiFive implementation of the RISC-V Platform Level
Interrupt Controller (PLIC).  The PLIC connects global interrupt sources
to the local interrupt controller on each hart.

This driver is based on the driver in the RISC-V tree from Palmer Dabbelt,
but has been almost entirely rewritten since, and includes many fixes
from Atish Patra.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
[Binding update by Palmer]
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13 08:31:32 -07:00