[src/trunk]: src/sys/arch/arm/acpi arm: acpi: Improve legacy INTx support.

[jmcneill <jmcneill%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/2f3e895eff0a
branches:  trunk
changeset: 368939:2f3e895eff0a
user:      jmcneill <jmcneill%NetBSD.org@localhost>
date:      Sat Aug 13 20:07:13 2022 +0000

description:
arm: acpi: Improve legacy INTx support.

For devices on a bus with no direct _PRT, use the raw intr pin with the
parent bridge's slot number to derive a pin number that can be used to
lookup the pin -> irq mapping in the parent bus's _PRT.

diffstat:

 sys/arch/arm/acpi/acpi_pci_machdep.c |  37 ++++++++++++++++++++++++++++++-----
 1 files changed, 31 insertions(+), 6 deletions(-)

diffs (103 lines):

diff -r d7972e573168 -r 2f3e895eff0a sys/arch/arm/acpi/acpi_pci_machdep.c
--- a/sys/arch/arm/acpi/acpi_pci_machdep.c      Sat Aug 13 17:46:26 2022 +0000
+++ b/sys/arch/arm/acpi/acpi_pci_machdep.c      Sat Aug 13 20:07:13 2022 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: acpi_pci_machdep.c,v 1.21 2021/12/21 11:02:38 skrll Exp $ */
+/* $NetBSD: acpi_pci_machdep.c,v 1.22 2022/08/13 20:07:13 jmcneill Exp $ */
 
 /*-
  * Copyright (c) 2018, 2020 The NetBSD Foundation, Inc.
@@ -34,7 +34,7 @@
 #define        _INTR_PRIVATE
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: acpi_pci_machdep.c,v 1.21 2021/12/21 11:02:38 skrll Exp $");
+__KERNEL_RCSID(0, "$NetBSD: acpi_pci_machdep.c,v 1.22 2022/08/13 20:07:13 jmcneill Exp $");
 
 #include <sys/param.h>
 #include <sys/bus.h>
@@ -71,6 +71,8 @@
 struct acpi_pci_prt {
        u_int                           prt_segment;
        u_int                           prt_bus;
+       u_int                           prt_bridge_dev;
+       bool                            prt_derived;
        ACPI_HANDLE                     prt_handle;
        TAILQ_ENTRY(acpi_pci_prt)       prt_list;
 };
@@ -210,6 +212,8 @@
        struct acpi_devnode *ad;
        ACPI_HANDLE handle;
        int seg, bus, dev, func;
+       u_int bridge_dev = 0;
+       bool derived = false;
 
        seg = ap->ap_seg;
        handle = NULL;
@@ -225,10 +229,13 @@
                if (ad != NULL) {
                        handle = ad->ad_handle;
                } else {
-                       /* No routes defined for this bus, copy from parent */
+                       /* No routes defined for this bus, derive from parent */
                        TAILQ_FOREACH(prtp, &acpi_pci_irq_routes, prt_list)
-                               if (prtp->prt_bus == bus) {
+                               if (prtp->prt_bus == bus &&
+                                   prtp->prt_segment == seg) {
                                        handle = prtp->prt_handle;
+                                       bridge_dev = dev;
+                                       derived = true;
                                        break;
                                }
                }
@@ -244,8 +251,10 @@
        if (handle != NULL) {
                prt = kmem_alloc(sizeof(*prt), KM_SLEEP);
                prt->prt_bus = pba->pba_bus;
-               prt->prt_segment = ap->ap_seg;
+               prt->prt_segment = seg;
                prt->prt_handle = handle;
+               prt->prt_bridge_dev = bridge_dev;
+               prt->prt_derived = derived;
                TAILQ_INSERT_TAIL(&acpi_pci_irq_routes, prt, prt_list);
        }
 
@@ -375,6 +384,7 @@
        ACPI_HANDLE linksrc;
        ACPI_BUFFER buf;
        void *linkdev;
+       u_int pin;
 
        if (pa->pa_intrpin == PCI_INTERRUPT_PIN_NONE)
                return EINVAL;
@@ -386,6 +396,21 @@
        if (ACPI_FAILURE(acpi_get(prt->prt_handle, &buf, AcpiGetIrqRoutingTable)))
                return EIO;
 
+       /*
+        * For busses with no direct _PRT entry, derive the pin from the
+        * parent bridge.
+        */
+       if (prt->prt_derived) {
+               pin = (((pa->pa_rawintrpin + prt->prt_bridge_dev) - 1) % 4) + 1;
+       } else {
+               pin = pa->pa_intrpin;
+       }
+
+       aprint_debug("%s: bus=%u pin=%u pa_rawintrpin=%u pa_intrpin=%u "
+                    "pa_intrswiz=%u prt_bridge_dev=%u\n",
+                            __func__, pa->pa_bus, pin, pa->pa_rawintrpin,
+                    pa->pa_intrpin, pa->pa_intrswiz, prt->prt_bridge_dev);
+
        error = ENOENT;
        for (char *p = buf.Pointer; ; p += tab->Length) {
                tab = (ACPI_PCI_ROUTING_TABLE *)p;
@@ -393,7 +418,7 @@
                        break;
 
                if (pa->pa_device == ACPI_HIWORD(tab->Address) &&
-                   (pa->pa_intrpin - 1) == (tab->Pin & 3)) {
+                   (pin - 1) == (tab->Pin & 3)) {
                        if (tab->Source[0] != 0) {
                                if (ACPI_FAILURE(AcpiGetHandle(ACPI_ROOT_OBJECT, tab->Source, &linksrc)))
                                        goto done;