On Wed, 2017-07-26 at 10:35 +0530, Shilpasri G Bhat wrote:
> This patch adds support to set power-shifting-ratio for CPU-GPU which
> is used by OCC power capping algorithm.
>
> Signed-off-by: Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com>
Hi Shilpasri,
I started looking though this - a lot the comments to patch 1/3 apply
here so I'll stop repeating myself :).
Thanks,
Cyril
> ---
> Changes from V7:
> - Replaced sscanf with kstrtoint
>
> arch/powerpc/include/asm/opal-api.h | 4 +-
> arch/powerpc/include/asm/opal.h | 3 +
> arch/powerpc/platforms/powernv/Makefile | 2 +-
> arch/powerpc/platforms/powernv/opal-psr.c | 169
> +++++++++++++++++++++++++
> arch/powerpc/platforms/powernv/opal-wrappers.S | 2 +
> arch/powerpc/platforms/powernv/opal.c | 3 +
> 6 files changed, 181 insertions(+), 2 deletions(-)
> create mode 100644 arch/powerpc/platforms/powernv/opal-psr.c
>
> diff --git a/arch/powerpc/include/asm/opal-api.h
> b/arch/powerpc/include/asm/opal-api.h
> index c3e0c4a..0d37315 100644
> --- a/arch/powerpc/include/asm/opal-api.h
> +++ b/arch/powerpc/include/asm/opal-api.h
> @@ -193,7 +193,9 @@
> #define OPAL_NPU_MAP_LPAR 148
> #define OPAL_GET_POWERCAP 152
> #define OPAL_SET_POWERCAP 153
> -#define OPAL_LAST 153
> +#define OPAL_GET_PSR 154
> +#define OPAL_SET_PSR 155
> +#define OPAL_LAST 155
>
> /* Device tree flags */
>
> diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h
> index ec2087c..58b30a4 100644
> --- a/arch/powerpc/include/asm/opal.h
> +++ b/arch/powerpc/include/asm/opal.h
> @@ -269,6 +269,8 @@ int64_t opal_xive_set_vp_info(uint64_t vp,
> int64_t opal_xive_dump(uint32_t type, uint32_t id);
> int opal_get_powercap(u32 handle, int token, u32 *pcap);
> int opal_set_powercap(u32 handle, int token, u32 pcap);
> +int opal_get_power_shifting_ratio(u32 handle, int token, u32 *psr);
> +int opal_set_power_shifting_ratio(u32 handle, int token, u32 psr);
>
> /* Internal functions */
> extern int early_init_dt_scan_opal(unsigned long node, const char *uname,
> @@ -348,6 +350,7 @@ static inline int opal_get_async_rc(struct opal_msg msg)
> void opal_wake_poller(void);
>
> void opal_powercap_init(void);
> +void opal_psr_init(void);
>
> #endif /* __ASSEMBLY__ */
>
> diff --git a/arch/powerpc/platforms/powernv/Makefile
> b/arch/powerpc/platforms/powernv/Makefile
> index e79f806..9ed7d33 100644
> --- a/arch/powerpc/platforms/powernv/Makefile
> +++ b/arch/powerpc/platforms/powernv/Makefile
> @@ -2,7 +2,7 @@ obj-y += setup.o opal-wrappers.o opal.o
> opal-async.o idle.o
> obj-y += opal-rtc.o opal-nvram.o opal-lpc.o
> opal-flash.o
> obj-y += rng.o opal-elog.o opal-dump.o
> opal-sysparam.o opal-sensor.o
> obj-y += opal-msglog.o opal-hmi.o opal-power.o
> opal-irqchip.o
> -obj-y += opal-kmsg.o opal-powercap.o
> +obj-y += opal-kmsg.o opal-powercap.o opal-psr.o
>
> obj-$(CONFIG_SMP) += smp.o subcore.o subcore-asm.o
> obj-$(CONFIG_PCI) += pci.o pci-ioda.o npu-dma.o
> diff --git a/arch/powerpc/platforms/powernv/opal-psr.c
> b/arch/powerpc/platforms/powernv/opal-psr.c
> new file mode 100644
> index 0000000..07e3f78
> --- /dev/null
> +++ b/arch/powerpc/platforms/powernv/opal-psr.c
> @@ -0,0 +1,169 @@
> +/*
> + * PowerNV OPAL Power-Shifting-Ratio interface
> + *
> + * Copyright 2017 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.
> + */
> +
> +#define pr_fmt(fmt) "opal-psr: " fmt
> +
> +#include <linux/of.h>
> +#include <linux/kobject.h>
> +#include <linux/slab.h>
> +
> +#include <asm/opal.h>
> +
> +DEFINE_MUTEX(psr_mutex);
> +
> +static struct kobject *psr_kobj;
> +
> +struct psr_attr {
> + u32 handle;
> + struct kobj_attribute attr;
> +};
> +
> +static struct psr_attr *psr_attrs;
> +static struct kobject *psr_kobj;
> +
> +static ssize_t psr_show(struct kobject *kobj, struct kobj_attribute *attr,
> + char *buf)
> +{
> + struct psr_attr *psr_attr = container_of(attr, struct psr_attr, attr);
> + struct opal_msg msg;
> + int psr, ret, token;
> +
> + token = opal_async_get_token_interruptible();
> + if (token < 0) {
> + pr_devel("Failed to get token\n");
> + return token;
> + }
> +
> + mutex_lock(&psr_mutex);
> + ret = opal_get_power_shifting_ratio(psr_attr->handle, token, &psr);
__pa()
> + switch (ret) {
> + case OPAL_ASYNC_COMPLETION:
> + ret = opal_async_wait_response(token, &msg);
> + if (ret) {
> + pr_devel("Failed to wait for the async response %d\n",
> + ret);
> + goto out;
> + }
> + ret = opal_error_code(opal_get_async_rc(msg));
> + if (!ret)
> + ret = sprintf(buf, "%u\n", be32_to_cpu(psr));
> + break;
> + case OPAL_SUCCESS:
> + ret = sprintf(buf, "%u\n", be32_to_cpu(psr));
> + break;
> + default:
> + ret = opal_error_code(ret);
> + }
> +
> +out:
> + mutex_unlock(&psr_mutex);
> + opal_async_release_token(token);
Same comment as previous patch - I don't know if returning the -EINVAL
from opal_async_wait_response()... we should probably start deciding at
a higher level what to do...
> + return ret;
> +}
> +
> +static ssize_t psr_store(struct kobject *kobj, struct kobj_attribute *attr,
> + const char *buf, size_t count)
> +{
> + struct psr_attr *psr_attr = container_of(attr, struct psr_attr, attr);
> + struct opal_msg msg;
> + int psr, ret, token;
> +
> + ret = kstrtoint(buf, 0, &psr);
> + if (ret)
> + return ret;
> +
> + token = opal_async_get_token_interruptible();
> + if (token < 0) {
> + pr_devel("Failed to get token\n");
> + return token;
> + }
> +
> + mutex_lock(&psr_mutex);
> + ret = opal_set_power_shifting_ratio(psr_attr->handle, token, psr);
> + switch (ret) {
> + case OPAL_ASYNC_COMPLETION:
> + ret = opal_async_wait_response(token, &msg);
> + if (ret) {
> + pr_devel("Failed to wait for the async response %d\n",
> + ret);
> + goto out;
> + }
> + ret = opal_error_code(opal_get_async_rc(msg));
> + if (!ret)
> + ret = count;
> + break;
> + case OPAL_SUCCESS:
> + ret = count;
> + break;
> + default:
> + ret = opal_error_code(ret);
> + }
> +
> +out:
> + mutex_unlock(&psr_mutex);
> + opal_async_release_token(token);
> +
> + return ret;
> +}
> +
> +void __init opal_psr_init(void)
> +{
> + struct device_node *psr, *node;
> + int psr_attr_count = 0, i = 0;
> +
> + psr = of_find_node_by_path("/ibm,opal/power-mgt/psr");
> + if (!psr) {
> + pr_devel("/ibm,opal/power-mgt/psr node not found\n");
> + return;
> + }
> +
> + for_each_child_of_node(psr, node)
> + psr_attr_count++;
> +
> + psr_attrs = kcalloc(psr_attr_count, sizeof(struct psr_attr),
> + GFP_KERNEL);
> + if (!psr_attrs)
> + return;
> +
> + for_each_child_of_node(psr, node) {
> + if (of_property_read_u32(node, "handle",
> + &psr_attrs[i].handle))
> + goto out;
> +
> + sysfs_attr_init(&psr_attrs[i].attr.attr);
> + if (of_property_read_string(node, "label",
> + &psr_attrs[i].attr.attr.name))
> + goto out;
> + psr_attrs[i].attr.attr.mode = 0664;
> + psr_attrs[i].attr.show = psr_show;
> + psr_attrs[i].attr.store = psr_store;
> + i++;
> + }
> +
> + psr_kobj = kobject_create_and_add("psr", opal_kobj);
> + if (!psr_kobj) {
> + pr_warn("Failed to create psr kobkect\n");
Typo
> + goto out;
> + }
> +
> + for (i = 0; i < psr_attr_count; i++)
> + if (sysfs_create_file(psr_kobj, &psr_attrs[i].attr.attr)) {
> + pr_devel("Failed to create sysfs file %s\n",
> + psr_attrs[i].attr.attr.name);
> + goto out_kobj;
> +
Can't we do all that in the first loop?
> }
> +
> + return;
> +out_kobj:
> + kobject_put(psr_kobj);
> +out:
> + kfree(psr_attrs);
> +}
> diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S
> b/arch/powerpc/platforms/powernv/opal-wrappers.S
> index eff5fe7..9867726 100644
> --- a/arch/powerpc/platforms/powernv/opal-wrappers.S
> +++ b/arch/powerpc/platforms/powernv/opal-wrappers.S
> @@ -312,3 +312,5 @@ OPAL_CALL(opal_npu_destroy_context,
> OPAL_NPU_DESTROY_CONTEXT);
> OPAL_CALL(opal_npu_map_lpar, OPAL_NPU_MAP_LPAR);
> OPAL_CALL(opal_get_powercap, OPAL_GET_POWERCAP);
> OPAL_CALL(opal_set_powercap, OPAL_SET_POWERCAP);
> +OPAL_CALL(opal_get_power_shifting_ratio, OPAL_GET_PSR);
> +OPAL_CALL(opal_set_power_shifting_ratio, OPAL_SET_PSR);
> diff --git a/arch/powerpc/platforms/powernv/opal.c
> b/arch/powerpc/platforms/powernv/opal.c
> index 889da97..280a736 100644
> --- a/arch/powerpc/platforms/powernv/opal.c
> +++ b/arch/powerpc/platforms/powernv/opal.c
> @@ -839,6 +839,9 @@ static int __init opal_init(void)
> /* Initialise OPAL powercap interface */
> opal_powercap_init();
>
> + /* Initialise OPAL Power-Shifting-Ratio interface */
> + opal_psr_init();
> +
> return 0;
> }
> machine_subsys_initcall(powernv, opal_init);
