Re: [PATCH 2/2] gpio: sch: Add interrupt support

Jan Kiszka
2019-04-24T09:37:16Z

On 24.04.19 10:42, Mika Westerberg wrote:
> On Wed, Apr 24, 2019 at 10:25:40AM +0200, Jan Kiszka wrote:
>> On 24.04.19 10:18, Mika Westerberg wrote:
>>> On Wed, Apr 24, 2019 at 10:12:42AM +0200, Jan Kiszka wrote:
>>>> On 24.04.19 09:58, Mika Westerberg wrote:
>>>>> +Rafael and linux-acpi.
>>>>>
>>>>> On Thu, Apr 18, 2019 at 11:23:49AM +0200, Jan Kiszka wrote:
>>>>>> From: Jan Kiszka <jan.kiszka@siemens.com>
>>>>>>
>>>>>> Validated on the Quark platform, this adds interrupt support on rising
>>>>>> and/or falling edges.
>>>>>
>>>>> The irqchip parts look good to me but but the ACPI SCI handling seems
>>>>> weird. This is typically handled by ACPI core based on the values read
>>>>> from FADT ACPI table. What does it contain on this Quark platform?
>>>>
>>>> There is no FADT on the original Quark firmware, nor did we add one. As we
>>>> are talking about existing devices, possibly not only Quarks, I was going
>>>> down the ACPI-independent way to hook into the interrupt. But I'm open to
>>>> learn about better alternatives.
>>>
>>> Hmm, if it does not have FADT table why would you need SCI then? Is this
>>> implementing some real use case?
>>>
>>
>> Maybe I'm looking at the wrong place: Where would I find it? There is
>> definitely no separate entry under /sys/firmware/acpi/tables - but that's
>> also true for my workstation.
>
> The table signature and name is FACP for historical reasons.
>

OK, there is that table, but what is it supposed to tell me about the
event and where to hook into it better?

[000h 0000 4] Signature : "FACP" [Fixed ACPI Description Table (FADT)]
[004h 0004 4] Table Length : 000000F4
[008h 0008 1] Revision : 03
[009h 0009 1] Checksum : CB
[00Ah 0010 6] Oem ID : "INTEL "
[010h 0016 8] Oem Table ID : "TIANO "
[018h 0024 4] Oem Revision : 00000004
[01Ch 0028 4] Asl Compiler ID : "INTL"
[020h 0032 4] Asl Compiler Revision : 0100000D

[024h 0036 4] FACS Address : 371B7000
[028h 0040 4] DSDT Address : 37002000
[02Ch 0044 1] Model : 00
[02Dh 0045 1] PM Profile : 01 [Desktop]
[02Eh 0046 2] SCI Interrupt : 0009
[030h 0048 4] SMI Command Port : 000000B2
[034h 0052 1] ACPI Enable Value : A0
[035h 0053 1] ACPI Disable Value : A1
[036h 0054 1] S4BIOS Command : 00
[037h 0055 1] P-State Control : 00
[038h 0056 4] PM1A Event Block Address : 00001000
[03Ch 0060 4] PM1B Event Block Address : 00000000
[040h 0064 4] PM1A Control Block Address : 00001004
[044h 0068 4] PM1B Control Block Address : 00000000
[048h 0072 4] PM2 Control Block Address : 00000000
[04Ch 0076 4] PM Timer Block Address : 00001008
[050h 0080 4] GPE0 Block Address : 00001100
[054h 0084 4] GPE1 Block Address : 00000000
[058h 0088 1] PM1 Event Block Length : 04
[059h 0089 1] PM1 Control Block Length : 02
[05Ah 0090 1] PM2 Control Block Length : 00
[05Bh 0091 1] PM Timer Block Length : 04
[05Ch 0092 1] GPE0 Block Length : 08
[05Dh 0093 1] GPE1 Block Length : 00
[05Eh 0094 1] GPE1 Base Offset : 00
[05Fh 0095 1] _CST Support : 00
[060h 0096 2] C2 Latency : 0065
[062h 0098 2] C3 Latency : 03E9
[064h 0100 2] CPU Cache Size : 0400
[066h 0102 2] Cache Flush Stride : 0010
[068h 0104 1] Duty Cycle Offset : 01
[069h 0105 1] Duty Cycle Width : 03
[06Ah 0106 1] RTC Day Alarm Index : 00
[06Bh 0107 1] RTC Month Alarm Index : 00
[06Ch 0108 1] RTC Century Index : 00
[06Dh 0109 2] Boot Flags (decoded below) : 0001
Legacy Devices Supported (V2) : 1
8042 Present on ports 60/64 (V2) : 0
VGA Not Present (V4) : 0
MSI Not Supported (V4) : 0
PCIe ASPM Not Supported (V4) : 0
CMOS RTC Not Present (V5) : 0
[06Fh 0111 1] Reserved : 00
[070h 0112 4] Flags (decoded below) : 000084B5
WBINVD instruction is operational (V1) : 1
WBINVD flushes all caches (V1) : 0
All CPUs support C1 (V1) : 1
C2 works on MP system (V1) : 0
Control Method Power Button (V1) : 1
Control Method Sleep Button (V1) : 1
RTC wake not in fixed reg space (V1) : 0
RTC can wake system from S4 (V1) : 1
32-bit PM Timer (V1) : 0
Docking Supported (V1) : 0
Reset Register Supported (V2) : 1
Sealed Case (V3) : 0
Headless - No Video (V3) : 0
Use native instr after SLP_TYPx (V3) : 0
PCIEXP_WAK Bits Supported (V4) : 0
Use Platform Timer (V4) : 1
RTC_STS valid on S4 wake (V4) : 0
Remote Power-on capable (V4) : 0
Use APIC Cluster Model (V4) : 0
Use APIC Physical Destination Mode (V4) : 0
Hardware Reduced (V5) : 0
Low Power S0 Idle (V5) : 0

[074h 0116 12] Reset Register : [Generic Address Structure]
[074h 0116 1] Space ID : 01 [SystemIO]
[075h 0117 1] Bit Width : 08
[076h 0118 1] Bit Offset : 00
[077h 0119 1] Encoded Access Width : 00 [Undefined/Legacy]
[078h 0120 8] Address : 0000000000000CF9

[080h 0128 1] Value to cause reset : 02
[081h 0129 2] ARM Flags (decoded below) : 0000
PSCI Compliant : 0
Must use HVC for PSCI : 0

[083h 0131 1] FADT Minor Revision : 00
[084h 0132 8] FACS Address : 0000000000000000
[08Ch 0140 8] DSDT Address : 0000000037002000
[094h 0148 12] PM1A Event Block : [Generic Address Structure]
[094h 0148 1] Space ID : 01 [SystemIO]
[095h 0149 1] Bit Width : 20
[096h 0150 1] Bit Offset : 00
[097h 0151 1] Encoded Access Width : 00 [Undefined/Legacy]
[098h 0152 8] Address : 0000000000001000

[0A0h 0160 12] PM1B Event Block : [Generic Address Structure]
[0A0h 0160 1] Space ID : 01 [SystemIO]
[0A1h 0161 1] Bit Width : 00
[0A2h 0162 1] Bit Offset : 00
[0A3h 0163 1] Encoded Access Width : 00 [Undefined/Legacy]
[0A4h 0164 8] Address : 0000000000000000

[0ACh 0172 12] PM1A Control Block : [Generic Address Structure]
[0ACh 0172 1] Space ID : 01 [SystemIO]
[0ADh 0173 1] Bit Width : 10
[0AEh 0174 1] Bit Offset : 00
[0AFh 0175 1] Encoded Access Width : 00 [Undefined/Legacy]
[0B0h 0176 8] Address : 0000000000001004

[0B8h 0184 12] PM1B Control Block : [Generic Address Structure]
[0B8h 0184 1] Space ID : 01 [SystemIO]
[0B9h 0185 1] Bit Width : 00
[0BAh 0186 1] Bit Offset : 00
[0BBh 0187 1] Encoded Access Width : 00 [Undefined/Legacy]
[0BCh 0188 8] Address : 0000000000000000

[0C4h 0196 12] PM2 Control Block : [Generic Address Structure]
[0C4h 0196 1] Space ID : 01 [SystemIO]
[0C5h 0197 1] Bit Width : 00
[0C6h 0198 1] Bit Offset : 00
[0C7h 0199 1] Encoded Access Width : 00 [Undefined/Legacy]
[0C8h 0200 8] Address : 0000000000000000

[0D0h 0208 12] PM Timer Block : [Generic Address Structure]
[0D0h 0208 1] Space ID : 01 [SystemIO]
[0D1h 0209 1] Bit Width : 20
[0D2h 0210 1] Bit Offset : 00
[0D3h 0211 1] Encoded Access Width : 00 [Undefined/Legacy]
[0D4h 0212 8] Address : 0000000000001008

[0DCh 0220 12] GPE0 Block : [Generic Address Structure]
[0DCh 0220 1] Space ID : 01 [SystemIO]
[0DDh 0221 1] Bit Width : 40
[0DEh 0222 1] Bit Offset : 00
[0DFh 0223 1] Encoded Access Width : 00 [Undefined/Legacy]
[0E0h 0224 8] Address : 0000000000001100

[0E8h 0232 12] GPE1 Block : [Generic Address Structure]
[0E8h 0232 1] Space ID : 01 [SystemIO]
[0E9h 0233 1] Bit Width : 00
[0EAh 0234 1] Bit Offset : 00
[0EBh 0235 1] Encoded Access Width : 00 [Undefined/Legacy]
[0ECh 0236 8] Address : 0000000000000000

Raw Table Data: Length 244 (0xF4)

0000: 46 41 43 50 F4 00 00 00 03 CB 49 4E 54 45 4C 20 // FACP......INTEL
0010: 54 49 41 4E 4F 20 20 20 04 00 00 00 49 4E 54 4C // TIANO ....INTL
0020: 0D 00 00 01 00 70 1B 37 00 20 00 37 00 01 09 00 // .....p.7. .7....
0030: B2 00 00 00 A0 A1 00 00 00 10 00 00 00 00 00 00 // ................
0040: 04 10 00 00 00 00 00 00 00 00 00 00 08 10 00 00 // ................
0050: 00 11 00 00 00 00 00 00 04 02 00 04 08 00 00 00 // ................
0060: 65 00 E9 03 00 04 10 00 01 03 00 00 00 01 00 00 // e...............
0070: B5 84 00 00 01 08 00 00 F9 0C 00 00 00 00 00 00 // ................
0080: 02 00 00 00 00 00 00 00 00 00 00 00 00 20 00 37 // ............. .7
0090: 00 00 00 00 01 20 00 00 00 10 00 00 00 00 00 00 // ..... ..........
00A0: 01 00 00 00 00 00 00 00 00 00 00 00 01 10 00 00 // ................
00B0: 04 10 00 00 00 00 00 00 01 00 00 00 00 00 00 00 // ................
00C0: 00 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 // ................
00D0: 01 20 00 00 08 10 00 00 00 00 00 00 01 40 00 00 // . ...........@..
00E0: 00 11 00 00 00 00 00 00 01 00 00 00 00 00 00 00 // ................
00F0: 00 00 00 00 // ....

Jan

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