The original driver author seemed to be under the impression that a driver
cannot be removed if it does not have a .remove method. Or maybe if it is
a built-in platform driver.
This is not true. This crash can be created:
root@ubuntu:/sys/bus/platform/drivers/hisi-lpc# echo HISI0191\:00 > unbind
root@ubuntu:/sys/bus/platform/drivers/hisi-lpc# ipmitool raw 6 1
Unable to handle kernel paging request at virtual address ffff000010035010
Mem abort info:
ESR = 0x96000047
Exception class = DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
Data abort info:
ISV = 0, ISS = 0x00000047
CM = 0, WnR = 1
swapper pgtable: 4k pages, 48-bit VAs, pgdp=000000000118b000
[ffff000010035010] pgd=0000041ffbfff003, pud=0000041ffbffe003, pmd=0000041ffbffd003, pte=0000000000000000
Internal error: Oops: 96000047 [#1] PREEMPT SMP
Modules linked in:
CPU: 17 PID: 1473 Comm: ipmitool Not tainted 5.2.0-rc5-00003-gf68c53b414a3-dirty #198
Hardware name: Huawei Taishan 2280 /D05, BIOS Hisilicon D05 IT21 Nemo 2.0 RC0 04/18/2018
pstate: 20000085 (nzCv daIf -PAN -UAO)
pc : hisi_lpc_target_in+0x7c/0x120
lr : hisi_lpc_target_in+0x70/0x120
sp : ffff00001efe3930
x29: ffff00001efe3930 x28: ffff841f9f599200
x27: 0000000000000002 x26: 0000000000000000
x25: 0000000000000080 x24: 00000000000000e4
x23: 0000000000000000 x22: 0000000000000064
x21: ffff801fb667d280 x20: 0000000000000001
x19: ffff00001efe39ac x18: 0000000000000000
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000000 x14: 0000000000000000
x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000000000
x9 : 0000000000000000 x8 : ffff841febe60340
x7 : ffff801fb55c52e8 x6 : 0000000000000000
x5 : 0000000000ffc0e3 x4 : 0000000000000001
x3 : ffff801fb667d280 x2 : 0000000000000001
x1 : ffff000010035010 x0 : ffff000010035000
Call trace:
hisi_lpc_target_in+0x7c/0x120
hisi_lpc_comm_in+0x88/0x98
logic_inb+0x5c/0xb8
port_inb+0x18/0x20
bt_event+0x38/0x808
smi_event_handler+0x4c/0x5a0
check_start_timer_thread.part.4+0x40/0x58
sender+0x78/0x88
smi_send.isra.6+0x94/0x108
i_ipmi_request+0x2c4/0x8f8
ipmi_request_settime+0x124/0x160
handle_send_req+0x19c/0x208
ipmi_ioctl+0x2c0/0x990
do_vfs_ioctl+0xb8/0x8f8
ksys_ioctl+0x80/0xb8
__arm64_sys_ioctl+0x1c/0x28
el0_svc_common.constprop.0+0x64/0x160
el0_svc_handler+0x28/0x78
el0_svc+0x8/0xc
Code: 941d1511 aa0003f9 f94006a0 91004001 (b9000034)
---[ end trace aa842b86af7069e4 ]---
The problem here is that the host goes away but the associated logical PIO
region remains registered, as do the children devices.
Fix by adding a .remove method to tidy-up by removing the child devices
and unregistering the logical PIO region.
Cc: stable@vger.kernel.org
Fixes: adf38bb0b5 ("HISI LPC: Support the LPC host on Hip06/Hip07 with DT bindings")
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
If, after registering a logical PIO range, the driver probe later fails,
the logical PIO range memory will be released automatically.
This causes an issue, in that the logical PIO range is not unregistered
and the released range memory may be later referenced.
Fix by unregistering the logical PIO range.
And since we now unregister the logical PIO range for probe failure, avoid
the special ordering of setting logical PIO range ops, which was the
previous (poor) attempt at a safeguard against this.
Cc: stable@vger.kernel.org
Fixes: adf38bb0b5 ("HISI LPC: Support the LPC host on Hip06/Hip07 with DT bindings")
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Currently for ACPI-based FW we fail the probe for an unrecognised child
HID.
However, there is FW in the field with LPC child devices having fake HIDs,
namely "IPI0002", which was an IPMI device invented to support the
initial out-of-tree LPC host driver, different from the final mainline
version.
To provide compatibility support for these dodgy FWs, just discard the
unrecognised HIDs instead of failing the probe altogether.
Tested-by: Zengruan Ye <yezengruan@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
On the Huawei D03 development board the system UART is
the UART connected on the LPC bus.
The profile for the device driver required for this HW
is as follows:
- platform driver
- 16550
- ACPI support
- polling mode support
- IO space support
In principle we should use the PNP driver (8250_dw.c) for
8250-devices with ACPI FW. However since this driver does
not support PNP devices, and modifying the PNP core code
to support it is not worth the effort, use the generic
8250 isa driver.
For this, we setup the pdev platform data for the serial
8250 port.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Since we no longer use the MFD APIs to enumerate the
child devices on the bus, use the platform driver APIs
directly.
In this patch we iterate of the children devices for the
host, and create a platform device directly per child.
For the iterating, we match the child ACPI HID against a
known list of supported child devices and their respective
ACPIs HID, to find the device name and any other
supplementary data.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
The MFD APIs should only be used by drivers in
drivers/mfd. It is not worth splitting the driver to have
separate parts in drivers/bus and drivers/mfd, so just
drop MFD API usage.
As a solution, we will use the platform device APIs directly
to achieve the same as we had when using MFD APIs.
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Based on the previous patches, this patch supports the LPC host on
Hip06/Hip07 for ACPI FW.
It is the responsibility of the LPC host driver to enumerate the child
devices, as the ACPI scan code will not enumerate children of "indirect IO"
hosts.
The ACPI table for the LPC host controller and the child devices is in the
following format:
Device (LPC0) {
Name (_HID, "HISI0191") // HiSi LPC
Name (_CRS, ResourceTemplate () {
Memory32Fixed (ReadWrite, 0xa01b0000, 0x1000)
})
}
Device (LPC0.IPMI) {
Name (_HID, "IPI0001")
Name (LORS, ResourceTemplate() {
QWordIO (
ResourceConsumer,
MinNotFixed, // _MIF
MaxNotFixed, // _MAF
PosDecode,
EntireRange,
0x0, // _GRA
0xe4, // _MIN
0x3fff, // _MAX
0x0, // _TRA
0x04, // _LEN
, ,
BTIO
)
})
Since the IO resources of the child devices need to be translated from LPC
bus addresses to logical PIO addresses, and we shouldn't modify the
resources of the devices generated in the FW scan, a per-child MFD is
created as a substitute. The MFD IO resources will be the translated bus
addresses of the ACPI child.
Tested-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Zhichang Yuan <yuanzhichang@hisilicon.com>
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
The low-pin-count (LPC) interface of Hip06/Hip07 accesses I/O port space of
peripherals.
Implement the LPC host controller driver which performs the I/O operations
on the underlying hardware. We don't want to touch existing drivers such
as ipmi-bt, so this driver applies the indirect-IO introduced in the
previous patch after registering an indirect-IO node to the indirect-IO
devices list which will be searched by the I/O accessors to retrieve the
host-local I/O port.
The driver config is set as a bool instead of a tristate. The reason here
is that, by the very nature of the driver providing a logical PIO range, it
does not make sense to have this driver as a loadable module. Another more
specific reason is that the Huawei D03 board which includes Hip06 SoC
requires the LPC bus for UART console, so should be built in.
Tested-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Zou Rongrong <zourongrong@huawei.com>
Signed-off-by: Zhichang Yuan <yuanzhichang@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Rob Herring <robh@kernel.org> # dts part
John Garry