[v3,1/2] pci: Add a framework for quirks

In future we may want to be able to do fixups for specific PCI devices in
skiboot, so add a small framework for doing this.

This is not intended for the same purposes as quirks in the Linux kernel,
as the PCI devices that quirks can match for in skiboot are not properly
configured.  This is intended to enable having a custom path to make
changes that don't directly interact with the PCI device, for example
adding device tree entries.

Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
v2 [ruscur]: Drop dt_node from pci_handle_quirk() thanks to Gavin
---
 core/Makefile.inc   |  2 +-
 core/pci-quirk.c    | 41 +++++++++++++++++++++++++++++++++++++++++
 core/pci.c          |  3 +++
 include/pci-quirk.h | 35 +++++++++++++++++++++++++++++++++++
 4 files changed, 80 insertions(+), 1 deletion(-)
 create mode 100644 core/pci-quirk.c
 create mode 100644 include/pci-quirk.h

On 24/02/17 16:36, Russell Currey wrote:
> In future we may want to be able to do fixups for specific PCI devices in
> skiboot, so add a small framework for doing this.
>
> This is not intended for the same purposes as quirks in the Linux kernel,
> as the PCI devices that quirks can match for in skiboot are not properly
> configured.  This is intended to enable having a custom path to make
> changes that don't directly interact with the PCI device, for example
> adding device tree entries.
>
> Signed-off-by: Russell Currey <ruscur@russell.cc>
> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> ---
> v2 [ruscur]: Drop dt_node from pci_handle_quirk() thanks to Gavin

Looks fairly sensible to me.

Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>

> +#include <skiboot.h>
> +#include <pci.h>
> +#include <pci-quirk.h>
> +#include <ast.h>
> +
> +/* Quirks are: {fixup function, vendor ID, (device ID or PCI_ANY_ID)} */
> +static const struct pci_quirk quirk_table[] = {
> +	{0}

This adds a slightly silly sparse warning:

core/pci-quirk.c:71:10: warning: Using plain integer as NULL pointer

On Fri, Feb 24, 2017 at 04:36:45PM +1100, Russell Currey wrote:
>In future we may want to be able to do fixups for specific PCI devices in
>skiboot, so add a small framework for doing this.
>
>This is not intended for the same purposes as quirks in the Linux kernel,
>as the PCI devices that quirks can match for in skiboot are not properly
>configured.  This is intended to enable having a custom path to make
>changes that don't directly interact with the PCI device, for example
>adding device tree entries.
>
>Signed-off-by: Russell Currey <ruscur@russell.cc>
>Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>

With minor comments fixed as below, or to be fixed later. Not a
big deal.

>---
>v2 [ruscur]: Drop dt_node from pci_handle_quirk() thanks to Gavin
>---
> core/Makefile.inc   |  2 +-
> core/pci-quirk.c    | 41 +++++++++++++++++++++++++++++++++++++++++
> core/pci.c          |  3 +++
> include/pci-quirk.h | 35 +++++++++++++++++++++++++++++++++++
> 4 files changed, 80 insertions(+), 1 deletion(-)
> create mode 100644 core/pci-quirk.c
> create mode 100644 include/pci-quirk.h
>
>diff --git a/core/Makefile.inc b/core/Makefile.inc
>index ae3c2979..b09c30c0 100644
>--- a/core/Makefile.inc
>+++ b/core/Makefile.inc
>@@ -8,7 +8,7 @@ CORE_OBJS += pci-opal.o fast-reboot.o device.o exceptions.o trace.o affinity.o
> CORE_OBJS += vpd.o hostservices.o platform.o nvram.o nvram-format.o hmi.o
> CORE_OBJS += console-log.o ipmi.o time-utils.o pel.o pool.o errorlog.o
> CORE_OBJS += timer.o i2c.o rtc.o flash.o sensor.o ipmi-opal.o
>-CORE_OBJS += flash-subpartition.o bitmap.o buddy.o
>+CORE_OBJS += flash-subpartition.o bitmap.o buddy.o pci-quirk.o
>
> ifeq ($(SKIBOOT_GCOV),1)
> CORE_OBJS += gcov-profiling.o
>diff --git a/core/pci-quirk.c b/core/pci-quirk.c
>new file mode 100644
>index 00000000..93f613eb
>--- /dev/null
>+++ b/core/pci-quirk.c
>@@ -0,0 +1,41 @@
>+/* Copyright 2016 IBM Corp.
>+ *
>+ * Licensed under the Apache License, Version 2.0 (the "License");
>+ * you may not use this file except in compliance with the License.
>+ * You may obtain a copy of the License at
>+ *
>+ * 	http://www.apache.org/licenses/LICENSE-2.0
>+ *
>+ * Unless required by applicable law or agreed to in writing, software
>+ * distributed under the License is distributed on an "AS IS" BASIS,
>+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
>+ * implied.
>+ * See the License for the specific language governing permissions and
>+ * limitations under the License.
>+ */
>+
>+#include <skiboot.h>
>+#include <pci.h>
>+#include <pci-quirk.h>
>+#include <ast.h>
>+
>+/* Quirks are: {fixup function, vendor ID, (device ID or PCI_ANY_ID)} */
>+static const struct pci_quirk quirk_table[] = {
>+	{0}
>+};
>+
>+void pci_handle_quirk(struct phb *phb,
>+		      struct pci_device *pd,
>+		      uint16_t vendor_id,
>+		      uint16_t device_id)
>+{

The vendor_id and device_id can be got from struct pci_device::vdid
as mentioned in the comments for v1. So you needn't pass them via
arguments, but nothing is wrong here.

>+	const struct pci_quirk *quirks = quirk_table;
>+
>+	while (quirks->vendor_id) {
>+		if (vendor_id == quirks->vendor_id &&
>+		    (quirks->device_id == PCI_ANY_ID ||
>+		     device_id == quirks->device_id))
>+			quirks->fixup(phb, pd);
>+		quirks++;
>+	}
>+}
>diff --git a/core/pci.c b/core/pci.c
>index 9889dbf8..fe4e73d8 100644
>--- a/core/pci.c
>+++ b/core/pci.c
>@@ -20,6 +20,7 @@
> #include <pci-cfg.h>
> #include <pci-iov.h>
> #include <pci-slot.h>
>+#include <pci-quirk.h>
> #include <timebase.h>
> #include <device.h>
> #include <fsp.h>
>@@ -1430,6 +1431,8 @@ static void pci_add_one_device_node(struct phb *phb,
> 	if (intpin)
> 		dt_add_property_cells(np, "interrupts", intpin);
>
>+	pci_handle_quirk(phb, pd, vdid & 0xffff, vdid >> 16);
>+
> 	/* XXX FIXME: Add a few missing ones such as
> 	 *
> 	 *  - devsel-speed (!express)
>diff --git a/include/pci-quirk.h b/include/pci-quirk.h
>new file mode 100644
>index 00000000..c7669733
>--- /dev/null
>+++ b/include/pci-quirk.h
>@@ -0,0 +1,35 @@
>+/* Copyright 2016 IBM Corp.

2017 maybe?

>+ *
>+ * Licensed under the Apache License, Version 2.0 (the "License");
>+ * you may not use this file except in compliance with the License.
>+ * You may obtain a copy of the License at
>+ *
>+ * 	http://www.apache.org/licenses/LICENSE-2.0
>+ *
>+ * Unless required by applicable law or agreed to in writing, software
>+ * distributed under the License is distributed on an "AS IS" BASIS,
>+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
>+ * implied.
>+ * See the License for the specific language governing permissions and
>+ * limitations under the License.
>+ */
>+
>+#ifndef __PCI_QUIRK_H
>+#define __PCI_QUIRK_H
>+
>+#include <pci.h>
>+
>+#define PCI_ANY_ID 0xFFFF
>+
>+struct pci_quirk {
>+	void (*fixup)(struct phb *, struct pci_device *);
>+	uint16_t vendor_id;
>+	uint16_t device_id;
>+};
>+
>+void pci_handle_quirk(struct phb *phb,
>+		      struct pci_device *pd,
>+		      uint16_t vendor_id,
>+		      uint16_t device_id);
>+
>+#endif /* __PCI_QUIRK_H */
>-- 
>2.11.1
>

Russell Currey <ruscur@russell.cc> writes:
> In future we may want to be able to do fixups for specific PCI devices in
> skiboot, so add a small framework for doing this.
>
> This is not intended for the same purposes as quirks in the Linux kernel,
> as the PCI devices that quirks can match for in skiboot are not properly
> configured.  This is intended to enable having a custom path to make
> changes that don't directly interact with the PCI device, for example
> adding device tree entries.
>
> Signed-off-by: Russell Currey <ruscur@russell.cc>
> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> ---
> v2 [ruscur]: Drop dt_node from pci_handle_quirk() thanks to Gavin
> ---

Series merged to master as of fcb5114c426119dedb0226137d4a3468462f979f