[lkml]   [2018]   [Feb]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH v13 7/9] ACPI: Translate the I/O range of non-MMIO devices before scanning
> Nothing apart from only being used by arm64 platforms today, which is
> circumstantial.
>> I understand you need to find a place to add the:
>> acpi_indirect_io_scan_init()
>> to be called from core ACPI code because ACPI can't handle probe
>> dependencies in any other way but other than that this patch is
>> a Hisilicon ACPI driver - there is nothing generic in it (or at
>> least there are no standard bindings to make it so).
>> Whether a callback from ACPI core code (acpi_scan_init()) to a driver
>> specific hook is sane or not that's the question and the only reason
>> why you want to add this in drivers/acpi/arm64 rather than, say,
>> drivers/bus (as you do for the DT driver).
>> I do not know Rafael's opinion on the above, I would like to help
>> you make forward progress but please understand my concerns, mostly
>> on FW side.
> I did mention an alternative in my "ping" in v12 patch 7/9 (Feb 1), but
> no response to this specific note so I kept on the same path.
> Here's what I then wrote:
> "I think another solution - which you may prefer - is to avoid adding
> this scan handler (and all this other scan code) and add a check like
> acpi_is_serial_bus_slave() [which checks the device parent versus a list
> of known indirectIO hosts] to not enumerate these children, and do it
> from the LLDD host probe instead ("

Hi Rafael, Lorenzo,

I can avoid adding the scan handler in acpi_indirectio.c by skipping the
child enumeration, like with this change in scan.c:

+static const struct acpi_device_id indirect_io_hosts[] = {
+ {"HISI0191", 0}, /* HiSilicon LPC host */
+ {},
+static bool acpi_is_indirect_io_slave(struct acpi_device *device)
+ struct acpi_device *parent = dev->parent;
+ if (!parent || acpi_match_device_ids(parent, indirect_io_hosts))
+ return false;
+ return true;
static bool acpi_is_serial_bus_slave(struct acpi_device *device)
struct list_head resource_list;
bool is_serial_bus_slave = false;

+ if (acpi_is_indirect_io_slave(device))
+ return true;
/* Macs use device properties in lieu of _CRS resources */

This means I can move all this scan code into the LLDD.

What do you think? Please let me know.


 \ /
  Last update: 2018-02-15 12:19    [W:0.360 / U:1.880 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site