Hi Andrew,
> From: Andrew Jeffery <and...@codeconstruct.com.au>
> Sent: Wednesday, February 5, 2025 11:51 AM
> To: Jamin Lin <jamin_...@aspeedtech.com>; Cédric Le Goater <c...@kaod.org>;
> Peter Maydell <peter.mayd...@linaro.org>; Steven Lee
> <steven_...@aspeedtech.com>; Troy Lee <leet...@gmail.com>; Joel Stanley
> <j...@jms.id.au>; open list:ASPEED BMCs <qemu-...@nongnu.org>; open
> list:All patches CC here <qemu-devel@nongnu.org>
> Cc: Troy Lee <troy_...@aspeedtech.com>; Yunlin Tang
> <yunlin.t...@aspeedtech.com>
> Subject: Re: [PATCH v1 12/18] hw/arm/aspeed_ast27x0: Support two levels of
> INTC controllers for AST2700 A1
>
> On Tue, 2025-02-04 at 09:43 +0000, Jamin Lin wrote:
> > Hi Andrew,
> >
> > > -----Original Message-----
> > > From: Andrew Jeffery <and...@codeconstruct.com.au>
> > > Sent: Thursday, January 30, 2025 12:20 PM
> > > To: Jamin Lin <jamin_...@aspeedtech.com>; Cédric Le Goater
> > > <c...@kaod.org>; Peter Maydell <peter.mayd...@linaro.org>; Steven Lee
> > > <steven_...@aspeedtech.com>; Troy Lee <leet...@gmail.com>; Joel
> > > Stanley <j...@jms.id.au>; open list:ASPEED BMCs
> > > <qemu-...@nongnu.org>; open list:All patches CC here
> > > <qemu-devel@nongnu.org>
> > > Cc: Troy Lee <troy_...@aspeedtech.com>; Yunlin Tang
> > > <yunlin.t...@aspeedtech.com>
> > > Subject: Re: [PATCH v1 12/18] hw/arm/aspeed_ast27x0: Support two
> > > levels of INTC controllers for AST2700 A1
> > >
> > > On Tue, 2025-01-21 at 15:04 +0800, Jamin Lin wrote:
> > > > The design of INTC controllers has significantly changed in AST2700 A1.
> > > >
> > > > There are a total of 480 interrupt sources in AST2700 A1. For
> > > > interrupt numbers from 0 to 127, they can route directly to PSP,
> > > > SSP, and TSP. Due to the limitation of interrupt numbers of
> > > > processors, the interrupts are merged every
> > > > 32 sources for interrupt numbers greater than 127.
> > > >
> > > > There are two levels of interrupt controllers, INTC0 and INTC1.
> > > > The interrupt sources of INTC0 are the interrupt numbers from
> > > > INTC_0 to
> > > > INTC_127 and interrupts from INTC1. The interrupt sources of INTC1
> > > > are the interrupt numbers greater than INTC_127. INTC1 controls
> > > > the interrupts
> > > INTC_128 to INTC_319 only.
> > > >
> > > > Currently, only GIC 192 to 201 are supported, and their source
> > > > interrupts are from INTC1 and connected to INTC0 at input pin 0
> > > > and output pins 0 to 9 for GIC 192-201.
> > > >
> > > > To support both AST2700 A1 and A0, INTC0 input pins 1 to 9 and
> > > > output pins
> > > > 10 to 18 remain to support GIC 128-136, which source interrupts from
> INTC0.
> > > > These will be removed if we decide not to support AST2700 A0 in the
> future.
> > > >
> > > > +---------------------------------------------------------------------------------------+
> > > > > AST2700 A1
> > > Design
> > > > > >
> > > >
> > > >
> > >
> > > > > >
> > > >
> > > > +--------------------------+
> > >
> > > > > >
> > > >
> > > > | INTC1 |
> > >
> > > > > +---------------+ |
> > > >
> > > > | |
> > > |
> > > > > orgates[0] | |
> > > > > orgates[0]+----> |inpin[0]+------->outpin[0]+------> |
> > > 0
> > > > > > |
> > > > > orgates[1]|----> |inpin[1]|------->outpin[1]|------> | 1
> > > > > 0-31 bits +--+ |
> > > > > orgates[2]|----> |inpin[2]|------->outpin[2]|------> |
> > > 2
> > > > > > | |
> > > > > orgates[3]|----> |inpin[3]|------->outpin[3]|------> |
> > > 3
> > > > > > | |
> > > > > orgates[4]|----> |inpin[4]|------->outpin[4]|------> |
> > > 4
> > > > > > | |
> > > > > orgates[5]+----> |inpin[5]+------->outpin[5]+------> |
> > > 5
> > > > > > | |
> > > >
> > > > | |
> > >
> > > > > > ---------------| | |
> > > >
> > > > +--------------------------+
> > >
> > > > > > |
> > > > >
> > > > > +---------------------------------------------------------------
> > > > > +----
> > > > > ----| |
> > > >
> > > > |
> > >
> > > > > >
> > > >
> > > > |
> > >
> > > > > >
> > > > > | +------------------------------+
> > > > > +-----------------+ |
> > > >
> > >
> > | | INTC0 |
> > > |
> > > > > GIC | |
> > > > > | |inpin[0:0]--------->outpin[0] +--------->
> > > > 192
> > > > > > |
> > > > > | |inpin[0:1]|-------->outpin[1] |--------->
> > > > 193
> > > > > > |
> > > > > | |inpin[0:2]|-------->outpin[2] |--------->
> > > > 194
> > > > > > |
> > > > > | |inpin[0:3]|-------->outpin[3] |--------->
> > > > 195
> > > > > > |
> > > > > >--------------> |inpin[0:4]|-------->outpin[4] |--------->
> > > > 196
> > > > > > |
> > > > > |inpin[0:5]|-------->outpin[5] |--------->
> > > > 197
> > > > > > |
> > > > > |inpin[0:6]|-------->outpin[6] |--------->
> > > > 198
> > > > > > |
> > > > > |inpin[0:7]|-------->outpin[7] |--------->
> > > > 199
> > > > > > |
> > > > > |inpin[0:8]|-------->outpin[8] |--------->
> > > > 200
> > > > > > |
> > > > > |inpin[0:9]|-------->outpin[9] |--------->
> > > > 201
> > > > > > |
> > > > +---------------------------------------------------------------------------------------+
> > > > +---------------------------------------------------------------------------------------+
> > > > > orgates[1]|-----> |inpin[1]|---------->outpin[10]|--------->
> > > > 128
> > > > > > |
> > > > > orgates[2]|-----> |inpin[2]|---------->outpin[11]|--------->
> > > > 129
> > > > > > |
> > > > > orgates[3]|-----> |inpin[3]|---------->outpin[12]|--------->
> > > > 130
> > > > > > |
> > > > > orgates[4]|-----> |inpin[4]|---------->outpin[13]|--------->
> > > > 131
> > > > > > |
> > > > > orgates[5]|-----> |inpin[5]|---------->outpin[14]|--------->
> > > > 132
> > > > > > |
> > > > > orgates[6]|-----> |inpin[6]|---------->outpin[15]|--------->
> > > > 133
> > > > > > |
> > > > > orgates[7]|-----> |inpin[7]|---------->outpin[16]|--------->
> > > > 134
> > > > > > |
> > > > > orgates[8]|-----> |inpin[8]|---------->outpin[17]|--------->
> > > > 135
> > > > > > |
> > > > > orgates[9]+-----> |inpin[9]|---------->outpin[18]+--------->
> > > > 136
> > > > > > |
> > > > > +------------------------------+
> > > > > +-----------------+ |
> > > >
> > > >
> > >
> > > > > >
> > > > > AST2700 A0
> > > Design
> > >
> > > > > >
> > > >
> > > >
> > >
> > > > > >
> > > > +---------------------------------------------------------------------------------------+
> > > >
> > >
> > > Okay, so I think this is the diagram and discussion I asked for as
> > > documentation earlier. I still prefer it doesn't just live in a
> > > commit message, that you pull it out to a separate document that we can
> easily point to and evolve.
> > >
> > INTC drivers owners update DTS binding document here,
> > https://patchwork.kernel.org/project/linux-arm-kernel/patch/2024101602
> > 2410.1154574-2-kevin_c...@aspeedtech.com/
>
> The diagram there is relatively straight-forward, but I suspect the devil is
> in the
> details.
>
> >
> >
> > > I'm a little hazy on some of your notation in diagram though. Can
> > > you explain your use of pipes ("|"), plusses ("+"), the "orgates" to
> > > the left of INTC1 (what are they ORing?), and the choice of 5 lines
> > > into the "orgates[0]" box? Also why does the "orgates[0]" arrow point
> > > where
> it does on INTC0?
> > >
> > I created this block diagram using the asciiflow tool and both ("I") and
> > "("+")
> symbols are identical.
> > I will update the diagram and replace ("+") with ("|").
> > Sorry to make you confuse.
>
> Ah, right.
>
> >
> > The design of the OR gates for GICINT 196 is as follows:
>
> 196? You discuss 192 below.
>
Sorry typo. I update my comments.
The design of the OR gates for GICINT 196 is as follows:
It has interrupt sources ranging from 0 to 31, with its output pin connected to
INTC_IO "T0 GICINT_196".
The output pin is then connected to INTC_CPU "GIC_192_201" at bit 4, and
its bit 4 output should be connected to GIC 196.
The design of INTC_CPU GIC_192_201 have 10 output pins, mapped as following:
Bit 0 -> GIC 192
Bit 1 -> GIC 193
Bit 2 -> GIC 194
Bit 3 -> GIC 195
Bit 4 -> GIC 196
Jamin
|-------------------------------------------------------------------------------------------------------|
| AST2700 A1 Design
|
| To GICINT196
|
|
|
| ETH1 |-----------| |--------------------------|
|--------------| |
| -------->|0 | | INTC_IO |
| orgates[0] | |
| ETH2 | 4|
orgates[0]------>|inpin[0]-------->outpin[0]|------->| 0 | |
| -------->|1 5|
orgates[1]------>|inpin[1]-------->outpin[1]|------->| 1 | |
| ETH3 | 6|
orgates[2]------>|inpin[2]-------->outpin[2]|------->| 2 | |
| -------->|2 19|
orgates[3]------>|inpin[3]-------->outpin[3]|------->| 3 OR[0:9] |-----| |
| UART0 |
20|-->orgates[4]------>|inpin[4]-------->outpin[4]|------->| 4 |
| |
| -------->|7 21|
orgates[5]------>|inpin[5]-------->outpin[5]|------->| 5 | | |
| UART1 | 22|
orgates[6]------>|inpin[6]-------->outpin[6]|------->| 6 | | |
| -------->|8 23|
orgates[7]------>|inpin[7]-------->outpin[7]|------->| 7 | | |
| UART2 | 24|
orgates[8]------>|inpin[8]-------->outpin[8]|------->| 8 | | |
| -------->|9 25|
orgates[9]------>|inpin[9]-------->outpin[9]|------->| 9 | | |
| UART3 | 26| |--------------------------|
|--------------| | |
| ---------|10 27|
| |
| UART5 | 28|
| |
| -------->|11 29|
| |
| UART6 | |
| |
| -------->|12 30|
|-----------------------------------------------------------------------| |
| UART7 | 31| |
|
| -------->|13 | |
|
| UART8 | OR[0:31] | |
|------------------------------| |----------| |
| -------->|14 | | | INTC
| | GIC | |
| UART9 | | |
|inpin[0:0]--------->outpin[0] |---------->|192 | |
| -------->|15 | |
|inpin[0:1]--------->outpin[1] |---------->|193 | |
| UART10 | | |
|inpin[0:2]--------->outpin[2] |---------->|194 | |
| -------->|16 | |
|inpin[0:3]--------->outpin[3] |---------->|195 | |
| UART11 | | |-------------->
|inpin[0:4]--------->outpin[4] |---------->|196 | |
| -------->|17 |
|inpin[0:5]--------->outpin[5] |---------->|197 | |
| UART12 | |
|inpin[0:6]--------->outpin[6] |---------->|198 | |
| -------->|18 |
|inpin[0:7]--------->outpin[7] |---------->|199 | |
| |-----------|
|inpin[0:8]--------->outpin[8] |---------->|200 | |
|
|inpin[0:9]--------->outpin[9] |---------->|201 | |
|-------------------------------------------------------------------------------------------------------|
|-------------------------------------------------------------------------------------------------------|
| ETH1 |-----------|
orgates[1]------->|inpin[1]|---------->outpin[10]|---------->|128 | |
| -------->|0 |
orgates[2]------->|inpin[2]|---------->outpin[11]|---------->|129 | |
| ETH2 | 4|
orgates[3]------->|inpin[3]|---------->outpin[12]|---------->|130 | |
| -------->|1 5|
orgates[4]------->|inpin[4]|---------->outpin[13]|---------->|131 | |
| ETH3 |
6|---->orgates[5]------->|inpin[5]|---------->outpin[14]|---------->|132
| |
| -------->|2 19|
orgates[6]------->|inpin[6]|---------->outpin[15]|---------->|133 | |
| UART0 | 20|
orgates[7]------->|inpin[7]|---------->outpin[16]|---------->|134 | |
| -------->|7 21|
orgates[8]------->|inpin[8]|---------->outpin[17]|---------->|135 | |
| UART1 | 22|
orgates[9]------->|inpin[9]|---------->outpin[18]|---------->|136 | |
| -------->|8 23|
|------------------------------| |----------| |
| UART2 | 24|
|
| -------->|9 25| AST2700 A0 Design
|
| UART3 | 26|
|
| -------->|10 27|
|
| UART5 | 28|
|
| -------->|11 29| GICINT132
|
| UART6 | |
|
| -------->|12 30|
|
| UART7 | 31|
|
| -------->|13 |
|
| UART8 | OR[0:31] |
|
| -------->|14 |
|
| UART9 | |
|
| -------->|15 |
|
| UART10 | |
|
| -------->|16 |
|
| UART11 | |
|
| -------->|17 |
|
| UART12 | |
|
| -------->|18 |
|
| |-----------|
|
|
|
|-------------------------------------------------------------------------------------------------------|
> >
> > Our firmware only utilizes bits 0 to 5, so I have only illustrated bits 0
> > to 5 in
> the diagram. However, I have implemented bits 0 to 9 in the code.
> > It has interrupt sources ranging from 0 to 31, with its output pin
> > connected to
> INTC_IO "T0 GICINTC_192".
> > The output pin is then connected to INTC_CPU "GIC_192_201" at bit 0, and
> its bit 0 output should be connected to GIC 192.
> >
> > The design of INTC_CPU GIC_192_201 have 10 output pins, mapped as
> following:
> > Bit 0 --> GIC 192
> > BIT 1 -> GIC 193
> > BIT 2-> GIC 194
> >
> > Our firmware only utilizes bits 0 to 5, so I have only illustrated bits 0
> > to 5 in
> the diagram. However, I have implemented bits 0 to 9 in the code.
>
> Ah, okay, this is helpful context.
>
> >
> > Then, orgates[0] "or" the output pins of INTC_IO (To GIC192, To
> > GIC193, To GIC194, To GIC195, To GIC196)
> >
> > ETH1 +-----------+
> > +--------v+0 3+
> > ETH2 | 4|
> > +-------->+1 5|
> > ETH3 | 6|
> > +-------->+2 19|
> > UART0 | 20|
> > +-------->+7 21|
> > UART1 | 22|
> > +-------->+8 23|
> > UART2 | 24|
> > +-------->+9 25|
> > UART3 | 26|
> > +--------->10 27|
> > UART5 | 28|
> > +-------->+11 29|
> > UART6 | |
> > +-------->+12 30|
> > UART7 | 31|
> > +-------->+13 |
> > UART8 | OR[0:31] |
> > +--------->14 |
> > UART9 | |
> > +-------->+15 |
> > UART10 | |
> > +-------->+16 |
> > UART11 | |
> > +-------->+17 |
> > UART12 | |
> > +--------->18 |
> > | |
> > | |
> > | |
> > +-----------+
> >
> > https://github.com/AspeedTech-BMC/linux/blob/aspeed-master-v6.6/arch/a
> > rm64/boot/dts/aspeed/aspeed-g7.dtsi#L483
> > https://github.com/AspeedTech-BMC/linux/blob/aspeed-master-v6.6/arch/a
> > rm64/boot/dts/aspeed/aspeed-g7.dtsi#L1610
>
> Let me absorb this and develop my own understanding in conjunction with the
> datasheet. It may take a few days.
>
> Andrew
