On Fri, Mar 04, 2022 at 07:59:15AM +0000, Marc Zyngier wrote: > On Thu, 03 Mar 2022 04:02:29 +0000, > Shawn Guo <shawn.guo@xxxxxxxxxx> wrote: > > > > On Wed, Mar 02, 2022 at 01:57:27PM +0000, Marc Zyngier wrote: > > > This code actually makes me ask more questions. Why is it programming > > > 2 'pins' for each IRQ? > > > > The mapping between MPM pin and GIC IRQ is not strictly 1-1. There are > > some rare case that up to 2 MPM pins map to a single GIC IRQ, for > > example the last two in QC2290 'qcom,mpm-pin-map' below. > > > > qcom,mpm-pin-map = <2 275>, /* tsens0_tsens_upper_lower_int */ > > <5 296>, /* lpass_irq_out_sdc */ > > <12 422>, /* b3_lfps_rxterm_irq */ > > <24 79>, /* bi_px_lpi_1_aoss_mx */ > > <86 183>, /* mpm_wake,spmi_m */ > > <90 260>, /* eud_p0_dpse_int_mx */ > > <91 260>; /* eud_p0_dmse_int_mx */ > > > > > > The downstream uses a DT bindings that specifies GIC hwirq number in > > client device nodes. In that case, d->hwirq in the driver is GIC IRQ > > number, and the driver will need to query mapping table, find out the > > possible 2 MPM pins, and set them up. > > > > The patches I'm posting here use a different bindings that specifies MPM > > pin instead in client device nodes. Thus the driver can simply get the > > MPM pin from d->hwirq, so that the whole look-up procedure can be saved. > > It still remains that there is no 1:1 mapping between input and > output, which is the rule #1 to be able to use a hierarchical setup. For direction of MPM pin -> GIC interrupt, it's a 1:1 mapping, i.e. for given MPM pin, there is only one GIC interrupt. And that's the mapping MPM driver relies on. For GIC interrupt -> MPM pin, it's not a strict 1:1 mapping. For given GIC interrupt, there could be up to 2 MPM pin mapped to it. MPM driver doesn't use this direction of mapping though. > > /me puzzled. > > > > > > > > > > > > > > It seems MPM_REG_POLARITY is only meant for level interrupts, since edge > > > > interrupts already have separate registers for rising and falling. > > > > > > Then level interrupts must clear both the edge registers at all times. > > > > The downstream logic already covers that, right? The edge register bits > > will be cleared as long as 'flowtype' is not EDGE. > > I am talking about *your* code, not the Qualcomm stuff. OK. If you do not see anything wrong on the vendor code logic, I plan to replace my broken code with it. Shawn
