Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-05-24 Thread Sukadev Bhattiprolu 
Tyrel Datwyler [tyr...@linux.vnet.ibm.com] wrote:
> > +   vinst = _instances[0];
> > +   for_each_node_by_name(dn, "vas") {
> > +   rc = init_vas_instance(dn, vinst);
> > +   if (rc) {
> > +   pr_err("Error %d initializing VAS instance %ld\n", rc,
> > +   (vinst-_instances[0]));
> 
> You need a of_node_put(dn) here. The for_each_node_by_name() loop will 
> get/put the
> references of the device_node for you. However, if you bail out of the loop 
> you are
> responsible for the of_node_put() on the current *dn reference otherwise you 
> will leak a
> reference.

Thanks for the pointing it out.  Based on Ben's comments, I have modified this
code and no longer need to break out of the loop.

Sukadev

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-05-24 Thread Sukadev Bhattiprolu 
Tyrel Datwyler [tyr...@linux.vnet.ibm.com] wrote:
> > +   vinst = _instances[0];
> > +   for_each_node_by_name(dn, "vas") {
> > +   rc = init_vas_instance(dn, vinst);
> > +   if (rc) {
> > +   pr_err("Error %d initializing VAS instance %ld\n", rc,
> > +   (vinst-_instances[0]));
> 
> You need a of_node_put(dn) here. The for_each_node_by_name() loop will 
> get/put the
> references of the device_node for you. However, if you bail out of the loop 
> you are
> responsible for the of_node_put() on the current *dn reference otherwise you 
> will leak a
> reference.

Thanks for the pointing it out.  Based on Ben's comments, I have modified this
code and no longer need to break out of the loop.

Sukadev

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-24 Thread Tyrel Datwyler 
On 03/30/2017 10:13 PM, Sukadev Bhattiprolu wrote:
> Implement vas_init() and vas_exit() functions for a new VAS module.
> This VAS module is essentially a library for other device drivers
> and kernel users of the NX coprocessors like NX-842 and NX-GZIP.
> In the future this will be extended to add support for user space
> to access the NX coprocessors.
> 
> Signed-off-by: Sukadev Bhattiprolu 
> ---
> Changelog[v4]:
>   - [Michael Neuling] Fix some accidental deletions; fix help text
> in Kconfig; change vas_initialized to a function; move from
> drivers/misc to arch/powerpc/kernel
>   - Drop the vas_window_reset() interface. It is not needed as
> window will be initialized before each use.
> Changelog[v3]:
>   - Zero vas_instances memory on allocation
>   - [Haren Myneni] Fix description in Kconfig
> Changelog[v2]:
>   - Get HVWC, UWC and window address parameters from device tree.
> ---
>  arch/powerpc/platforms/powernv/Kconfig  |  14 +++
>  arch/powerpc/platforms/powernv/Makefile |   1 +
>  arch/powerpc/platforms/powernv/vas-window.c |  19 
>  arch/powerpc/platforms/powernv/vas.c| 145 
> 
>  arch/powerpc/platforms/powernv/vas.h|   3 +
>  5 files changed, 182 insertions(+)
>  create mode 100644 arch/powerpc/platforms/powernv/vas-window.c
>  create mode 100644 arch/powerpc/platforms/powernv/vas.c
> 
> diff --git a/arch/powerpc/platforms/powernv/Kconfig 
> b/arch/powerpc/platforms/powernv/Kconfig
> index 3a07e4d..54e2a4e 100644
> --- a/arch/powerpc/platforms/powernv/Kconfig
> +++ b/arch/powerpc/platforms/powernv/Kconfig
> @@ -27,3 +27,17 @@ config OPAL_PRD
>   help
> This enables the opal-prd driver, a facility to run processor
> recovery diagnostics on OpenPower machines
> +
> +config VAS
> + tristate "IBM Virtual Accelerator Switchboard (VAS)"
> + depends on PPC_POWERNV
> + default n
> + help
> +   This enables support for IBM Virtual Accelerator Switchboard (VAS).
> +
> +   VAS allows accelerators in co-processors like NX-GZIP and NX-842
> +   to be accessible to kernel subsystems.
> +
> +   VAS adapters are found in POWER9 based systems.
> +
> +   If unsure, say N.
> diff --git a/arch/powerpc/platforms/powernv/Makefile 
> b/arch/powerpc/platforms/powernv/Makefile
> index b5d98cb..ebef20b 100644
> --- a/arch/powerpc/platforms/powernv/Makefile
> +++ b/arch/powerpc/platforms/powernv/Makefile
> @@ -12,3 +12,4 @@ obj-$(CONFIG_PPC_SCOM)  += opal-xscom.o
>  obj-$(CONFIG_MEMORY_FAILURE) += opal-memory-errors.o
>  obj-$(CONFIG_TRACEPOINTS)+= opal-tracepoints.o
>  obj-$(CONFIG_OPAL_PRD)   += opal-prd.o
> +obj-$(CONFIG_VAS)+= vas.o vas-window.o
> diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
> b/arch/powerpc/platforms/powernv/vas-window.c
> new file mode 100644
> index 000..6156fbe
> --- /dev/null
> +++ b/arch/powerpc/platforms/powernv/vas-window.c
> @@ -0,0 +1,19 @@
> +/*
> + * Copyright 2016 IBM Corp.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#include 
> +#include 
> +
> +#include "vas.h"
> +
> +/* stub for now */
> +int vas_win_close(struct vas_window *window)
> +{
> + return -1;
> +}
> diff --git a/arch/powerpc/platforms/powernv/vas.c 
> b/arch/powerpc/platforms/powernv/vas.c
> new file mode 100644
> index 000..9bf8f57
> --- /dev/null
> +++ b/arch/powerpc/platforms/powernv/vas.c
> @@ -0,0 +1,145 @@
> +/*
> + * Copyright 2016 IBM Corp.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +
> +#include "vas.h"
> +
> +static bool init_done;
> +int vas_num_instances;
> +struct vas_instance *vas_instances;
> +
> +static int init_vas_instance(struct device_node *dn,
> + struct vas_instance *vinst)
> +{
> + int rc;
> + const __be32 *p;
> + u64 values[6];
> +
> + ida_init(>ida);
> + mutex_init(>mutex);
> +
> + p = of_get_property(dn, "vas-id", NULL);
> + if (!p) {
> + pr_err("VAS: NULL vas-id? %p\n", p);
> + return -ENODEV;
> + }
> +
> + vinst->vas_id = of_read_number(p, 1);
> +
> + /*
> +  * Hardcoded 6 is tied to corresponding code in
> +  *  skiboot.git/core/vas.c
> +  */
> + rc = of_property_read_variable_u64_array(dn, "reg", values, 6, 6);
> + if (rc != 6) {
> + pr_err("VAS %d: Unable to read reg properties, rc %d\n",
> +

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-24 Thread Tyrel Datwyler 
On 03/30/2017 10:13 PM, Sukadev Bhattiprolu wrote:
> Implement vas_init() and vas_exit() functions for a new VAS module.
> This VAS module is essentially a library for other device drivers
> and kernel users of the NX coprocessors like NX-842 and NX-GZIP.
> In the future this will be extended to add support for user space
> to access the NX coprocessors.
> 
> Signed-off-by: Sukadev Bhattiprolu 
> ---
> Changelog[v4]:
>   - [Michael Neuling] Fix some accidental deletions; fix help text
> in Kconfig; change vas_initialized to a function; move from
> drivers/misc to arch/powerpc/kernel
>   - Drop the vas_window_reset() interface. It is not needed as
> window will be initialized before each use.
> Changelog[v3]:
>   - Zero vas_instances memory on allocation
>   - [Haren Myneni] Fix description in Kconfig
> Changelog[v2]:
>   - Get HVWC, UWC and window address parameters from device tree.
> ---
>  arch/powerpc/platforms/powernv/Kconfig  |  14 +++
>  arch/powerpc/platforms/powernv/Makefile |   1 +
>  arch/powerpc/platforms/powernv/vas-window.c |  19 
>  arch/powerpc/platforms/powernv/vas.c| 145 
> 
>  arch/powerpc/platforms/powernv/vas.h|   3 +
>  5 files changed, 182 insertions(+)
>  create mode 100644 arch/powerpc/platforms/powernv/vas-window.c
>  create mode 100644 arch/powerpc/platforms/powernv/vas.c
> 
> diff --git a/arch/powerpc/platforms/powernv/Kconfig 
> b/arch/powerpc/platforms/powernv/Kconfig
> index 3a07e4d..54e2a4e 100644
> --- a/arch/powerpc/platforms/powernv/Kconfig
> +++ b/arch/powerpc/platforms/powernv/Kconfig
> @@ -27,3 +27,17 @@ config OPAL_PRD
>   help
> This enables the opal-prd driver, a facility to run processor
> recovery diagnostics on OpenPower machines
> +
> +config VAS
> + tristate "IBM Virtual Accelerator Switchboard (VAS)"
> + depends on PPC_POWERNV
> + default n
> + help
> +   This enables support for IBM Virtual Accelerator Switchboard (VAS).
> +
> +   VAS allows accelerators in co-processors like NX-GZIP and NX-842
> +   to be accessible to kernel subsystems.
> +
> +   VAS adapters are found in POWER9 based systems.
> +
> +   If unsure, say N.
> diff --git a/arch/powerpc/platforms/powernv/Makefile 
> b/arch/powerpc/platforms/powernv/Makefile
> index b5d98cb..ebef20b 100644
> --- a/arch/powerpc/platforms/powernv/Makefile
> +++ b/arch/powerpc/platforms/powernv/Makefile
> @@ -12,3 +12,4 @@ obj-$(CONFIG_PPC_SCOM)  += opal-xscom.o
>  obj-$(CONFIG_MEMORY_FAILURE) += opal-memory-errors.o
>  obj-$(CONFIG_TRACEPOINTS)+= opal-tracepoints.o
>  obj-$(CONFIG_OPAL_PRD)   += opal-prd.o
> +obj-$(CONFIG_VAS)+= vas.o vas-window.o
> diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
> b/arch/powerpc/platforms/powernv/vas-window.c
> new file mode 100644
> index 000..6156fbe
> --- /dev/null
> +++ b/arch/powerpc/platforms/powernv/vas-window.c
> @@ -0,0 +1,19 @@
> +/*
> + * Copyright 2016 IBM Corp.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#include 
> +#include 
> +
> +#include "vas.h"
> +
> +/* stub for now */
> +int vas_win_close(struct vas_window *window)
> +{
> + return -1;
> +}
> diff --git a/arch/powerpc/platforms/powernv/vas.c 
> b/arch/powerpc/platforms/powernv/vas.c
> new file mode 100644
> index 000..9bf8f57
> --- /dev/null
> +++ b/arch/powerpc/platforms/powernv/vas.c
> @@ -0,0 +1,145 @@
> +/*
> + * Copyright 2016 IBM Corp.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation; either version
> + * 2 of the License, or (at your option) any later version.
> + */
> +
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +#include 
> +
> +#include "vas.h"
> +
> +static bool init_done;
> +int vas_num_instances;
> +struct vas_instance *vas_instances;
> +
> +static int init_vas_instance(struct device_node *dn,
> + struct vas_instance *vinst)
> +{
> + int rc;
> + const __be32 *p;
> + u64 values[6];
> +
> + ida_init(>ida);
> + mutex_init(>mutex);
> +
> + p = of_get_property(dn, "vas-id", NULL);
> + if (!p) {
> + pr_err("VAS: NULL vas-id? %p\n", p);
> + return -ENODEV;
> + }
> +
> + vinst->vas_id = of_read_number(p, 1);
> +
> + /*
> +  * Hardcoded 6 is tied to corresponding code in
> +  *  skiboot.git/core/vas.c
> +  */
> + rc = of_property_read_variable_u64_array(dn, "reg", values, 6, 6);
> + if (rc != 6) {
> + pr_err("VAS %d: Unable to read reg properties, rc %d\n",
> +

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-24 Thread Benjamin Herrenschmidt 
On Thu, 2017-03-30 at 22:13 -0700, Sukadev Bhattiprolu wrote:
> 
> + p = of_get_property(dn, "vas-id", NULL);
> + if (!p) {
> + pr_err("VAS: NULL vas-id? %p\n", p);
> + return -ENODEV;
> + }
> +
> + vinst->vas_id = of_read_number(p, 1);

of_property_read_u32()

> + /*
> +  * Hardcoded 6 is tied to corresponding code in
> +  *  skiboot.git/core/vas.c
> +  */
> + rc = of_property_read_variable_u64_array(dn, "reg", values,
> 6, 6);
> + if (rc != 6) {
> + pr_err("VAS %d: Unable to read reg properties, rc
> %d\n",
> + vinst->vas_id, rc);
> + return rc;
> + }
> +
> + vinst->hvwc_bar_start = values[0];
> + vinst->hvwc_bar_len = values[1];
> + vinst->uwc_bar_start = values[2];
> + vinst->uwc_bar_len = values[3];
> + vinst->win_base_addr = values[4];
> + vinst->win_id_shift = values[5];

If you make the VAS a proper MMIO device on the powerbus (as explained
in my comment to your OPAL patch), and you create this as a platform
device based on the DT, the core will parse the reg property for you
and will populate the device struct resource array for you.

> + return 0;
> +}
> +
> +/*
> + * Although this is read/used multiple times, it is written to only
> + * during initialization.
> + */
> +struct vas_instance *find_vas_instance(int vasid)
> +{
> + int i;
> + struct vas_instance *vinst;
> +
> + for (i = 0; i < vas_num_instances; i++) {
> + vinst = _instances[i];
> + if (vinst->vas_id == vasid)
> + return vinst;
> + }
> + pr_err("VAS instance for vas-id %d not found\n", vasid);
> + WARN_ON_ONCE(1);
> + return NULL;
> +}

This is gross. What is it needed for  ?

> +
> +bool vas_initialized(void)
> +{
> + return init_done;
> +}
> +
> +int vas_init(void)
> +{
> + int rc;
> + struct device_node *dn;
> + struct vas_instance *vinst;
> +
> + if (!pvr_version_is(PVR_POWER9))
> + return -ENODEV;

No. Create a platform device that matches the corresponding device-tree
node. One per instance.

The resulting VAS "driver" thus becomes a loadable module which you can
put elsewhere in the tree, matching on the DT node "compatible"
property.

You can then have the copros be chilren of it. The VAS driver can then
create additional platform devices for its children, who can have their
own module (which *can* depend on symbols exportd by the VAS one)
etc...

> + vas_num_instances = 0;
> + for_each_node_by_name(dn, "vas")
> + vas_num_instances++;
> +
> + if (!vas_num_instances)
> + return -ENODEV;
> +
> + vas_instances = kcalloc(vas_num_instances, sizeof(*vinst),
> GFP_KERNEL);
> + if (!vas_instances)
> + return -ENOMEM;
> +
> + vinst = _instances[0];
> + for_each_node_by_name(dn, "vas") {
> + rc = init_vas_instance(dn, vinst);
> + if (rc) {
> + pr_err("Error %d initializing VAS instance
> %ld\n", rc,
> + (vinst-_instances[0]));
> + goto cleanup;
> + }
> + vinst++;
> + }
> +
> + rc = -ENODEV;
> + if (vinst == _instances[0]) {
> + /* Should not happen as we saw some above. */
> + pr_err("VAS: Did not find any VAS DT nodes now!\n");
> + goto cleanup;
> + }
> +
> + pr_devel("VAS: Initialized %d instances\n",
> vas_num_instances);
> + init_done = true;
> +
> + return 0;
> +
> +cleanup:
> + kfree(vas_instances);
> + return rc;
> +}
> +
> +void vas_exit(void)
> +{
> + init_done = false;
> + kfree(vas_instances);
> +}
> +
> +module_init(vas_init);
> +module_exit(vas_exit);
> +MODULE_DESCRIPTION("IBM Virtual Accelerator Switchboard");
> +MODULE_AUTHOR("Sukadev Bhattiprolu ");
> +MODULE_LICENSE("GPL");
> diff --git a/arch/powerpc/platforms/powernv/vas.h
> b/arch/powerpc/platforms/powernv/vas.h
> index c63395d..46aaa17 100644
> --- a/arch/powerpc/platforms/powernv/vas.h
> +++ b/arch/powerpc/platforms/powernv/vas.h
> @@ -384,4 +384,7 @@ struct vas_winctx {
>   enum vas_notify_after_count notify_after_count;
>  };
>  
> +extern bool vas_initialized(void);
> +extern struct vas_instance *find_vas_instance(int vasid);
> +
>  #endif /* _VAS_H */

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-24 Thread Benjamin Herrenschmidt 
On Thu, 2017-03-30 at 22:13 -0700, Sukadev Bhattiprolu wrote:
> 
> + p = of_get_property(dn, "vas-id", NULL);
> + if (!p) {
> + pr_err("VAS: NULL vas-id? %p\n", p);
> + return -ENODEV;
> + }
> +
> + vinst->vas_id = of_read_number(p, 1);

of_property_read_u32()

> + /*
> +  * Hardcoded 6 is tied to corresponding code in
> +  *  skiboot.git/core/vas.c
> +  */
> + rc = of_property_read_variable_u64_array(dn, "reg", values,
> 6, 6);
> + if (rc != 6) {
> + pr_err("VAS %d: Unable to read reg properties, rc
> %d\n",
> + vinst->vas_id, rc);
> + return rc;
> + }
> +
> + vinst->hvwc_bar_start = values[0];
> + vinst->hvwc_bar_len = values[1];
> + vinst->uwc_bar_start = values[2];
> + vinst->uwc_bar_len = values[3];
> + vinst->win_base_addr = values[4];
> + vinst->win_id_shift = values[5];

If you make the VAS a proper MMIO device on the powerbus (as explained
in my comment to your OPAL patch), and you create this as a platform
device based on the DT, the core will parse the reg property for you
and will populate the device struct resource array for you.

> + return 0;
> +}
> +
> +/*
> + * Although this is read/used multiple times, it is written to only
> + * during initialization.
> + */
> +struct vas_instance *find_vas_instance(int vasid)
> +{
> + int i;
> + struct vas_instance *vinst;
> +
> + for (i = 0; i < vas_num_instances; i++) {
> + vinst = _instances[i];
> + if (vinst->vas_id == vasid)
> + return vinst;
> + }
> + pr_err("VAS instance for vas-id %d not found\n", vasid);
> + WARN_ON_ONCE(1);
> + return NULL;
> +}

This is gross. What is it needed for  ?

> +
> +bool vas_initialized(void)
> +{
> + return init_done;
> +}
> +
> +int vas_init(void)
> +{
> + int rc;
> + struct device_node *dn;
> + struct vas_instance *vinst;
> +
> + if (!pvr_version_is(PVR_POWER9))
> + return -ENODEV;

No. Create a platform device that matches the corresponding device-tree
node. One per instance.

The resulting VAS "driver" thus becomes a loadable module which you can
put elsewhere in the tree, matching on the DT node "compatible"
property.

You can then have the copros be chilren of it. The VAS driver can then
create additional platform devices for its children, who can have their
own module (which *can* depend on symbols exportd by the VAS one)
etc...

> + vas_num_instances = 0;
> + for_each_node_by_name(dn, "vas")
> + vas_num_instances++;
> +
> + if (!vas_num_instances)
> + return -ENODEV;
> +
> + vas_instances = kcalloc(vas_num_instances, sizeof(*vinst),
> GFP_KERNEL);
> + if (!vas_instances)
> + return -ENOMEM;
> +
> + vinst = _instances[0];
> + for_each_node_by_name(dn, "vas") {
> + rc = init_vas_instance(dn, vinst);
> + if (rc) {
> + pr_err("Error %d initializing VAS instance
> %ld\n", rc,
> + (vinst-_instances[0]));
> + goto cleanup;
> + }
> + vinst++;
> + }
> +
> + rc = -ENODEV;
> + if (vinst == _instances[0]) {
> + /* Should not happen as we saw some above. */
> + pr_err("VAS: Did not find any VAS DT nodes now!\n");
> + goto cleanup;
> + }
> +
> + pr_devel("VAS: Initialized %d instances\n",
> vas_num_instances);
> + init_done = true;
> +
> + return 0;
> +
> +cleanup:
> + kfree(vas_instances);
> + return rc;
> +}
> +
> +void vas_exit(void)
> +{
> + init_done = false;
> + kfree(vas_instances);
> +}
> +
> +module_init(vas_init);
> +module_exit(vas_exit);
> +MODULE_DESCRIPTION("IBM Virtual Accelerator Switchboard");
> +MODULE_AUTHOR("Sukadev Bhattiprolu ");
> +MODULE_LICENSE("GPL");
> diff --git a/arch/powerpc/platforms/powernv/vas.h
> b/arch/powerpc/platforms/powernv/vas.h
> index c63395d..46aaa17 100644
> --- a/arch/powerpc/platforms/powernv/vas.h
> +++ b/arch/powerpc/platforms/powernv/vas.h
> @@ -384,4 +384,7 @@ struct vas_winctx {
>   enum vas_notify_after_count notify_after_count;
>  };
>  
> +extern bool vas_initialized(void);
> +extern struct vas_instance *find_vas_instance(int vasid);
> +
>  #endif /* _VAS_H */

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-24 Thread Benjamin Herrenschmidt 
On Thu, 2017-03-30 at 22:13 -0700, Sukadev Bhattiprolu wrote:
> +config VAS
> +   tristate "IBM Virtual Accelerator Switchboard (VAS)"

CONFIG_IBM_VAS or PPC_VAS ... too high risk of collision otherwise

Ben.

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-24 Thread Benjamin Herrenschmidt 
On Thu, 2017-03-30 at 22:13 -0700, Sukadev Bhattiprolu wrote:
> +config VAS
> +   tristate "IBM Virtual Accelerator Switchboard (VAS)"

CONFIG_IBM_VAS or PPC_VAS ... too high risk of collision otherwise

Ben.

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-04 Thread Sukadev Bhattiprolu 
Sukadev Bhattiprolu [sukadevatlinux.vnet.ibm.com] wrote:
> Implement vas_init() and vas_exit() functions for a new VAS module.
> This VAS module is essentially a library for other device drivers
> and kernel users of the NX coprocessors like NX-842 and NX-GZIP.
> In the future this will be extended to add support for user space
> to access the NX coprocessors.

Add "depends on PPC_64K_PAGES" to the Kconfig for VAS.
---

>From ff6fb584282363f6917fd956ccac05822d1912d7 Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
Date: Thu, 12 Jan 2017 02:16:10 -0500
Subject: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

Implement vas_init() and vas_exit() functions for a new VAS module.
This VAS module is essentially a library for other device drivers
and kernel users of the NX coprocessors like NX-842 and NX-GZIP.
In the future this will be extended to add support for user space
to access the NX coprocessors.

VAS is currently only supported with 64K page size.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
Changelog[v4]:
- [Michael Neuling] Fix some accidental deletions; fix help text
  in Kconfig; change vas_initialized to a function; move from
  drivers/misc to arch/powerpc/kernel
- Drop the vas_window_reset() interface. It is not needed as
  window will be initialized before each use.
- Add a "depends on PPC_64K_PAGES"
Changelog[v3]:
- Zero vas_instances memory on allocation
- [Haren Myneni] Fix description in Kconfig
Changelog[v2]:
- Get HVWC, UWC and window address parameters from device tree.
---
 arch/powerpc/platforms/powernv/Kconfig  |  14 +++
 arch/powerpc/platforms/powernv/Makefile |   1 +
 arch/powerpc/platforms/powernv/vas-window.c |  19 
 arch/powerpc/platforms/powernv/vas.c| 145 
 arch/powerpc/platforms/powernv/vas.h|   3 +
 5 files changed, 182 insertions(+)
 create mode 100644 arch/powerpc/platforms/powernv/vas-window.c
 create mode 100644 arch/powerpc/platforms/powernv/vas.c

diff --git a/arch/powerpc/platforms/powernv/Kconfig 
b/arch/powerpc/platforms/powernv/Kconfig
index 3a07e4d..34c344c 100644
--- a/arch/powerpc/platforms/powernv/Kconfig
+++ b/arch/powerpc/platforms/powernv/Kconfig
@@ -27,3 +27,17 @@ config OPAL_PRD
help
  This enables the opal-prd driver, a facility to run processor
  recovery diagnostics on OpenPower machines
+
+config VAS
+   tristate "IBM Virtual Accelerator Switchboard (VAS)"
+   depends on PPC_POWERNV && PPC_64K_PAGES
+   default n
+   help
+ This enables support for IBM Virtual Accelerator Switchboard (VAS).
+
+ VAS allows accelerators in co-processors like NX-GZIP and NX-842
+ to be accessible to kernel subsystems.
+
+ VAS adapters are found in POWER9 based systems.
+
+ If unsure, say N.
diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index b5d98cb..ebef20b 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_PPC_SCOM)+= opal-xscom.o
 obj-$(CONFIG_MEMORY_FAILURE)   += opal-memory-errors.o
 obj-$(CONFIG_TRACEPOINTS)  += opal-tracepoints.o
 obj-$(CONFIG_OPAL_PRD) += opal-prd.o
+obj-$(CONFIG_VAS)  += vas.o vas-window.o
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
new file mode 100644
index 000..6156fbe
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include 
+#include 
+
+#include "vas.h"
+
+/* stub for now */
+int vas_win_close(struct vas_window *window)
+{
+   return -1;
+}
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
new file mode 100644
index 000..9bf8f57
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include "vas.h"
+
+static bool init_done;
+int vas_num_instances;
+struct vas_instance *vas_instances;
+
+static int init_vas_instance(struct device_node *dn,
+   struct vas_instance *vinst)
+{
+   int rc;
+   con

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-04 Thread Sukadev Bhattiprolu 
Sukadev Bhattiprolu [sukadevatlinux.vnet.ibm.com] wrote:
> Implement vas_init() and vas_exit() functions for a new VAS module.
> This VAS module is essentially a library for other device drivers
> and kernel users of the NX coprocessors like NX-842 and NX-GZIP.
> In the future this will be extended to add support for user space
> to access the NX coprocessors.

Add "depends on PPC_64K_PAGES" to the Kconfig for VAS.
---

>From ff6fb584282363f6917fd956ccac05822d1912d7 Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu 
Date: Thu, 12 Jan 2017 02:16:10 -0500
Subject: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

Implement vas_init() and vas_exit() functions for a new VAS module.
This VAS module is essentially a library for other device drivers
and kernel users of the NX coprocessors like NX-842 and NX-GZIP.
In the future this will be extended to add support for user space
to access the NX coprocessors.

VAS is currently only supported with 64K page size.

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v4]:
- [Michael Neuling] Fix some accidental deletions; fix help text
  in Kconfig; change vas_initialized to a function; move from
  drivers/misc to arch/powerpc/kernel
- Drop the vas_window_reset() interface. It is not needed as
  window will be initialized before each use.
- Add a "depends on PPC_64K_PAGES"
Changelog[v3]:
- Zero vas_instances memory on allocation
- [Haren Myneni] Fix description in Kconfig
Changelog[v2]:
- Get HVWC, UWC and window address parameters from device tree.
---
 arch/powerpc/platforms/powernv/Kconfig  |  14 +++
 arch/powerpc/platforms/powernv/Makefile |   1 +
 arch/powerpc/platforms/powernv/vas-window.c |  19 
 arch/powerpc/platforms/powernv/vas.c| 145 
 arch/powerpc/platforms/powernv/vas.h|   3 +
 5 files changed, 182 insertions(+)
 create mode 100644 arch/powerpc/platforms/powernv/vas-window.c
 create mode 100644 arch/powerpc/platforms/powernv/vas.c

diff --git a/arch/powerpc/platforms/powernv/Kconfig 
b/arch/powerpc/platforms/powernv/Kconfig
index 3a07e4d..34c344c 100644
--- a/arch/powerpc/platforms/powernv/Kconfig
+++ b/arch/powerpc/platforms/powernv/Kconfig
@@ -27,3 +27,17 @@ config OPAL_PRD
help
  This enables the opal-prd driver, a facility to run processor
  recovery diagnostics on OpenPower machines
+
+config VAS
+   tristate "IBM Virtual Accelerator Switchboard (VAS)"
+   depends on PPC_POWERNV && PPC_64K_PAGES
+   default n
+   help
+ This enables support for IBM Virtual Accelerator Switchboard (VAS).
+
+ VAS allows accelerators in co-processors like NX-GZIP and NX-842
+ to be accessible to kernel subsystems.
+
+ VAS adapters are found in POWER9 based systems.
+
+ If unsure, say N.
diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index b5d98cb..ebef20b 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_PPC_SCOM)+= opal-xscom.o
 obj-$(CONFIG_MEMORY_FAILURE)   += opal-memory-errors.o
 obj-$(CONFIG_TRACEPOINTS)  += opal-tracepoints.o
 obj-$(CONFIG_OPAL_PRD) += opal-prd.o
+obj-$(CONFIG_VAS)  += vas.o vas-window.o
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
new file mode 100644
index 000..6156fbe
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include 
+#include 
+
+#include "vas.h"
+
+/* stub for now */
+int vas_win_close(struct vas_window *window)
+{
+   return -1;
+}
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
new file mode 100644
index 000..9bf8f57
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include "vas.h"
+
+static bool init_done;
+int vas_num_instances;
+struct vas_instance *vas_instances;
+
+static int init_vas_instance(struct device_node *dn,
+   struct vas_instance *vinst)
+{
+   int rc;
+   const __be32 *p;
+   u64 values[6];
+
+   ida_init(>ida

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-02 Thread kbuild test robot 
Hi Sukadev,

[auto build test ERROR on powerpc/next]
[also build test ERROR on v4.11-rc4 next-20170331]
[if your patch is applied to the wrong git tree, please drop us a note to help 
improve the system]

url:
https://github.com/0day-ci/linux/commits/Sukadev-Bhattiprolu/Add-Power9-PVR/20170402-155232
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-allmodconfig (attached as .config)
compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget 
https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O 
~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc 

All errors (new ones prefixed by >>):

   In file included from arch/powerpc/platforms/powernv/vas.c:17:0:
>> arch/powerpc/platforms/powernv/vas.h:17:3: error: #error "TODO: Compute 
>> RMA/Paste-address for 4K pages."
# error "TODO: Compute RMA/Paste-address for 4K pages."
  ^

vim +17 arch/powerpc/platforms/powernv/vas.h

8d1d7c15 Sukadev Bhattiprolu 2017-03-30  11  #define _VAS_H
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  12  #include 
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  13  #include 
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  14  #include 
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  15  
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  16  #ifdef CONFIG_PPC_4K_PAGES
8d1d7c15 Sukadev Bhattiprolu 2017-03-30 @17  #  error "TODO: Compute 
RMA/Paste-address for 4K pages."
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  18  #else
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  19  #ifndef CONFIG_PPC_64K_PAGES
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  20  #  error "Unexpected Page size."

:: The code at line 17 was first introduced by commit
:: 8d1d7c159a85bf75ef7b06edf8f27ef56d6b4b3f VAS: Define macros, register 
fields and structures

:: TO: Sukadev Bhattiprolu 
:: CC: 0day robot 

---
0-DAY kernel test infrastructureOpen Source Technology Center
https://lists.01.org/pipermail/kbuild-all   Intel Corporation


.config.gz
Description: application/gzip

Re: [PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-04-02 Thread kbuild test robot 
Hi Sukadev,

[auto build test ERROR on powerpc/next]
[also build test ERROR on v4.11-rc4 next-20170331]
[if your patch is applied to the wrong git tree, please drop us a note to help 
improve the system]

url:
https://github.com/0day-ci/linux/commits/Sukadev-Bhattiprolu/Add-Power9-PVR/20170402-155232
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-allmodconfig (attached as .config)
compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget 
https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O 
~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc 

All errors (new ones prefixed by >>):

   In file included from arch/powerpc/platforms/powernv/vas.c:17:0:
>> arch/powerpc/platforms/powernv/vas.h:17:3: error: #error "TODO: Compute 
>> RMA/Paste-address for 4K pages."
# error "TODO: Compute RMA/Paste-address for 4K pages."
  ^

vim +17 arch/powerpc/platforms/powernv/vas.h

8d1d7c15 Sukadev Bhattiprolu 2017-03-30  11  #define _VAS_H
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  12  #include 
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  13  #include 
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  14  #include 
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  15  
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  16  #ifdef CONFIG_PPC_4K_PAGES
8d1d7c15 Sukadev Bhattiprolu 2017-03-30 @17  #  error "TODO: Compute 
RMA/Paste-address for 4K pages."
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  18  #else
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  19  #ifndef CONFIG_PPC_64K_PAGES
8d1d7c15 Sukadev Bhattiprolu 2017-03-30  20  #  error "Unexpected Page size."

:: The code at line 17 was first introduced by commit
:: 8d1d7c159a85bf75ef7b06edf8f27ef56d6b4b3f VAS: Define macros, register 
fields and structures

:: TO: Sukadev Bhattiprolu 
:: CC: 0day robot 

---
0-DAY kernel test infrastructureOpen Source Technology Center
https://lists.01.org/pipermail/kbuild-all   Intel Corporation


.config.gz
Description: application/gzip

[PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-03-30 Thread Sukadev Bhattiprolu 
Implement vas_init() and vas_exit() functions for a new VAS module.
This VAS module is essentially a library for other device drivers
and kernel users of the NX coprocessors like NX-842 and NX-GZIP.
In the future this will be extended to add support for user space
to access the NX coprocessors.

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v4]:
- [Michael Neuling] Fix some accidental deletions; fix help text
  in Kconfig; change vas_initialized to a function; move from
  drivers/misc to arch/powerpc/kernel
- Drop the vas_window_reset() interface. It is not needed as
  window will be initialized before each use.
Changelog[v3]:
- Zero vas_instances memory on allocation
- [Haren Myneni] Fix description in Kconfig
Changelog[v2]:
- Get HVWC, UWC and window address parameters from device tree.
---
 arch/powerpc/platforms/powernv/Kconfig  |  14 +++
 arch/powerpc/platforms/powernv/Makefile |   1 +
 arch/powerpc/platforms/powernv/vas-window.c |  19 
 arch/powerpc/platforms/powernv/vas.c| 145 
 arch/powerpc/platforms/powernv/vas.h|   3 +
 5 files changed, 182 insertions(+)
 create mode 100644 arch/powerpc/platforms/powernv/vas-window.c
 create mode 100644 arch/powerpc/platforms/powernv/vas.c

diff --git a/arch/powerpc/platforms/powernv/Kconfig 
b/arch/powerpc/platforms/powernv/Kconfig
index 3a07e4d..54e2a4e 100644
--- a/arch/powerpc/platforms/powernv/Kconfig
+++ b/arch/powerpc/platforms/powernv/Kconfig
@@ -27,3 +27,17 @@ config OPAL_PRD
help
  This enables the opal-prd driver, a facility to run processor
  recovery diagnostics on OpenPower machines
+
+config VAS
+   tristate "IBM Virtual Accelerator Switchboard (VAS)"
+   depends on PPC_POWERNV
+   default n
+   help
+ This enables support for IBM Virtual Accelerator Switchboard (VAS).
+
+ VAS allows accelerators in co-processors like NX-GZIP and NX-842
+ to be accessible to kernel subsystems.
+
+ VAS adapters are found in POWER9 based systems.
+
+ If unsure, say N.
diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index b5d98cb..ebef20b 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_PPC_SCOM)+= opal-xscom.o
 obj-$(CONFIG_MEMORY_FAILURE)   += opal-memory-errors.o
 obj-$(CONFIG_TRACEPOINTS)  += opal-tracepoints.o
 obj-$(CONFIG_OPAL_PRD) += opal-prd.o
+obj-$(CONFIG_VAS)  += vas.o vas-window.o
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
new file mode 100644
index 000..6156fbe
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include 
+#include 
+
+#include "vas.h"
+
+/* stub for now */
+int vas_win_close(struct vas_window *window)
+{
+   return -1;
+}
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
new file mode 100644
index 000..9bf8f57
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include "vas.h"
+
+static bool init_done;
+int vas_num_instances;
+struct vas_instance *vas_instances;
+
+static int init_vas_instance(struct device_node *dn,
+   struct vas_instance *vinst)
+{
+   int rc;
+   const __be32 *p;
+   u64 values[6];
+
+   ida_init(>ida);
+   mutex_init(>mutex);
+
+   p = of_get_property(dn, "vas-id", NULL);
+   if (!p) {
+   pr_err("VAS: NULL vas-id? %p\n", p);
+   return -ENODEV;
+   }
+
+   vinst->vas_id = of_read_number(p, 1);
+
+   /*
+* Hardcoded 6 is tied to corresponding code in
+*  skiboot.git/core/vas.c
+*/
+   rc = of_property_read_variable_u64_array(dn, "reg", values, 6, 6);
+   if (rc != 6) {
+   pr_err("VAS %d: Unable to read reg properties, rc %d\n",
+   vinst->vas_id, rc);
+   return rc;
+   }
+
+   vinst->hvwc_bar_start = values[0];
+   vinst->hvwc_bar_len = values[1];
+   vinst->uwc_bar_start = values[2];
+   vinst->uwc_bar_len = values[3];
+

[PATCH v4 04/11] VAS: Define vas_init() and vas_exit()

2017-03-30 Thread Sukadev Bhattiprolu 
Implement vas_init() and vas_exit() functions for a new VAS module.
This VAS module is essentially a library for other device drivers
and kernel users of the NX coprocessors like NX-842 and NX-GZIP.
In the future this will be extended to add support for user space
to access the NX coprocessors.

Signed-off-by: Sukadev Bhattiprolu 
---
Changelog[v4]:
- [Michael Neuling] Fix some accidental deletions; fix help text
  in Kconfig; change vas_initialized to a function; move from
  drivers/misc to arch/powerpc/kernel
- Drop the vas_window_reset() interface. It is not needed as
  window will be initialized before each use.
Changelog[v3]:
- Zero vas_instances memory on allocation
- [Haren Myneni] Fix description in Kconfig
Changelog[v2]:
- Get HVWC, UWC and window address parameters from device tree.
---
 arch/powerpc/platforms/powernv/Kconfig  |  14 +++
 arch/powerpc/platforms/powernv/Makefile |   1 +
 arch/powerpc/platforms/powernv/vas-window.c |  19 
 arch/powerpc/platforms/powernv/vas.c| 145 
 arch/powerpc/platforms/powernv/vas.h|   3 +
 5 files changed, 182 insertions(+)
 create mode 100644 arch/powerpc/platforms/powernv/vas-window.c
 create mode 100644 arch/powerpc/platforms/powernv/vas.c

diff --git a/arch/powerpc/platforms/powernv/Kconfig 
b/arch/powerpc/platforms/powernv/Kconfig
index 3a07e4d..54e2a4e 100644
--- a/arch/powerpc/platforms/powernv/Kconfig
+++ b/arch/powerpc/platforms/powernv/Kconfig
@@ -27,3 +27,17 @@ config OPAL_PRD
help
  This enables the opal-prd driver, a facility to run processor
  recovery diagnostics on OpenPower machines
+
+config VAS
+   tristate "IBM Virtual Accelerator Switchboard (VAS)"
+   depends on PPC_POWERNV
+   default n
+   help
+ This enables support for IBM Virtual Accelerator Switchboard (VAS).
+
+ VAS allows accelerators in co-processors like NX-GZIP and NX-842
+ to be accessible to kernel subsystems.
+
+ VAS adapters are found in POWER9 based systems.
+
+ If unsure, say N.
diff --git a/arch/powerpc/platforms/powernv/Makefile 
b/arch/powerpc/platforms/powernv/Makefile
index b5d98cb..ebef20b 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_PPC_SCOM)+= opal-xscom.o
 obj-$(CONFIG_MEMORY_FAILURE)   += opal-memory-errors.o
 obj-$(CONFIG_TRACEPOINTS)  += opal-tracepoints.o
 obj-$(CONFIG_OPAL_PRD) += opal-prd.o
+obj-$(CONFIG_VAS)  += vas.o vas-window.o
diff --git a/arch/powerpc/platforms/powernv/vas-window.c 
b/arch/powerpc/platforms/powernv/vas-window.c
new file mode 100644
index 000..6156fbe
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas-window.c
@@ -0,0 +1,19 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include 
+#include 
+
+#include "vas.h"
+
+/* stub for now */
+int vas_win_close(struct vas_window *window)
+{
+   return -1;
+}
diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
new file mode 100644
index 000..9bf8f57
--- /dev/null
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright 2016 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include "vas.h"
+
+static bool init_done;
+int vas_num_instances;
+struct vas_instance *vas_instances;
+
+static int init_vas_instance(struct device_node *dn,
+   struct vas_instance *vinst)
+{
+   int rc;
+   const __be32 *p;
+   u64 values[6];
+
+   ida_init(>ida);
+   mutex_init(>mutex);
+
+   p = of_get_property(dn, "vas-id", NULL);
+   if (!p) {
+   pr_err("VAS: NULL vas-id? %p\n", p);
+   return -ENODEV;
+   }
+
+   vinst->vas_id = of_read_number(p, 1);
+
+   /*
+* Hardcoded 6 is tied to corresponding code in
+*  skiboot.git/core/vas.c
+*/
+   rc = of_property_read_variable_u64_array(dn, "reg", values, 6, 6);
+   if (rc != 6) {
+   pr_err("VAS %d: Unable to read reg properties, rc %d\n",
+   vinst->vas_id, rc);
+   return rc;
+   }
+
+   vinst->hvwc_bar_start = values[0];
+   vinst->hvwc_bar_len = values[1];
+   vinst->uwc_bar_start = values[2];
+   vinst->uwc_bar_len = values[3];
+   vinst->win_base_addr =