Re: [PATCH v4 1/1] powerpc/pseries: Interface to represent PAPR firmware attributes
On 17/07/21 12:35 am, Fabiano Rosas wrote:
"Pratik R. Sampat" writes:
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
Do you need all of these headers? Sorry to mention just now, I seem to have
dropped this comment from a previous review.
Ah yes, that was a TODO on my part I had missed as cleanups.
I'll verify if I do need all of them and get back to you.
+
+#include "pseries.h"
+
+/*
+ * Flag attributes to fetch either all or one attribute from the HCALL
+ * flag = BE(0) => fetch all attributes with firstAttributeId = 0
+ * flag = BE(1) => fetch a single attribute with firstAttributeId = id
+ */
+#define ESI_FLAGS_ALL 0
+#define ESI_FLAGS_SINGLE PPC_BIT(0)
+
+#define MAX_ATTRS 3
+
+struct papr_attr {
+ u64 id;
+ struct kobj_attribute kobj_attr;
+};
+struct papr_group {
+ struct attribute_group pg;
+ struct papr_attr pgattrs[MAX_ATTRS];
+} *pgs;
+
+/* /sys/firmware/papr */
+struct kobject *papr_kobj;
+/* /sys/firmware/papr/energy_scale_info */
+struct kobject *esi_kobj;
+
+/*
+ * Extract and export the description of the energy scale attribute
+ *
Extra line here.
ack.
+ */
+static ssize_t papr_show_desc(struct kobject *kobj,
+ struct kobj_attribute *kobj_attr,
+ char *buf)
+{
+ struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr,
+ kobj_attr);
+ struct h_energy_scale_info_hdr *t_hdr;
+ struct energy_scale_attribute *t_esi;
+ char *t_buf;
+ int ret = 0;
+
+ t_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
+ if (t_buf == NULL)
+ return -ENOMEM;
+
+ ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE,
+pattr->id, virt_to_phys(t_buf),
+MAX_BUF_SZ);
+
+ if (ret != H_SUCCESS) {
+ pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
+ goto out;
+ }
+
+ t_hdr = (struct h_energy_scale_info_hdr *) t_buf;
+ t_esi = (struct energy_scale_attribute *)
+ (t_buf + be64_to_cpu(t_hdr->array_offset));
+
+ ret = snprintf(buf, sizeof(t_esi->desc), "%s\n", t_esi->desc);
+ if (ret < 0)
+ ret = -EIO;
+out:
+ kfree(t_buf);
+
+ return ret;
+}
+
+/*
+ * Extract and export the numeric value of the energy scale attributes
+ */
+static ssize_t papr_show_value(struct kobject *kobj,
+ struct kobj_attribute *kobj_attr,
+ char *buf)
+{
+ struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr,
+ kobj_attr);
+ struct h_energy_scale_info_hdr *t_hdr;
+ struct energy_scale_attribute *t_esi;
+ char *t_buf;
+ int ret = 0;
+
+ t_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
+ if (t_buf == NULL)
+ return -ENOMEM;
+
+ ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE,
+pattr->id, virt_to_phys(t_buf),
+MAX_BUF_SZ);
+
+ if (ret != H_SUCCESS) {
+ pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
+ goto out;
+ }
+
+ t_hdr = (struct h_energy_scale_info_hdr *) t_buf;
+ t_esi = (struct energy_scale_attribute *)
+ (t_buf + be64_to_cpu(t_hdr->array_offset));
+
+ ret = snprintf(buf, sizeof(t_esi->value), "%llu\n",
+ be64_to_cpu(t_esi->value));
+ if (ret < 0)
+ ret = -EIO;
+out:
+ kfree(t_buf);
+
+ return ret;
+}
+
+/*
+ * Extract and export the value description in string format of the energy
+ * scale attributes
+ */
+static ssize_t papr_show_value_desc(struct kobject *kobj,
+struct kobj_attribute *kobj_attr,
+char *buf)
+{
+ struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr,
+ kobj_attr);
+ struct h_energy_scale_info_hdr *t_hdr;
+ struct energy_scale_attribute *t_esi;
+ char *t_buf;
+ int ret = 0;
+
+ t_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
+ if (t_buf == NULL)
+ return -ENOMEM;
+
+ ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE,
+pattr->id, virt_to_phys(t_buf),
+MAX_BUF_SZ);
+
+ if (ret != H_SUCCESS) {
+ pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
+ goto out;
+ }
+
+ t_hdr = (struct h_energy_scale_info_hdr *) t_buf;
+ t_esi = (struct energy_scale_attribute *)
+ (t_buf +
Re: [PATCH v4 1/1] powerpc/pseries: Interface to represent PAPR firmware attributes
"Pratik R. Sampat" writes:
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
Do you need all of these headers? Sorry to mention just now, I seem to have
dropped this comment from a previous review.
> +
> +#include "pseries.h"
> +
> +/*
> + * Flag attributes to fetch either all or one attribute from the HCALL
> + * flag = BE(0) => fetch all attributes with firstAttributeId = 0
> + * flag = BE(1) => fetch a single attribute with firstAttributeId = id
> + */
> +#define ESI_FLAGS_ALL0
> +#define ESI_FLAGS_SINGLE PPC_BIT(0)
> +
> +#define MAX_ATTRS3
> +
> +struct papr_attr {
> + u64 id;
> + struct kobj_attribute kobj_attr;
> +};
> +struct papr_group {
> + struct attribute_group pg;
> + struct papr_attr pgattrs[MAX_ATTRS];
> +} *pgs;
> +
> +/* /sys/firmware/papr */
> +struct kobject *papr_kobj;
> +/* /sys/firmware/papr/energy_scale_info */
> +struct kobject *esi_kobj;
> +
> +/*
> + * Extract and export the description of the energy scale attribute
> + *
Extra line here.
> + */
> +static ssize_t papr_show_desc(struct kobject *kobj,
> +struct kobj_attribute *kobj_attr,
> +char *buf)
> +{
> + struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr,
> +kobj_attr);
> + struct h_energy_scale_info_hdr *t_hdr;
> + struct energy_scale_attribute *t_esi;
> + char *t_buf;
> + int ret = 0;
> +
> + t_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
> + if (t_buf == NULL)
> + return -ENOMEM;
> +
> + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE,
> + pattr->id, virt_to_phys(t_buf),
> + MAX_BUF_SZ);
> +
> + if (ret != H_SUCCESS) {
> + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
> + goto out;
> + }
> +
> + t_hdr = (struct h_energy_scale_info_hdr *) t_buf;
> + t_esi = (struct energy_scale_attribute *)
> + (t_buf + be64_to_cpu(t_hdr->array_offset));
> +
> + ret = snprintf(buf, sizeof(t_esi->desc), "%s\n", t_esi->desc);
> + if (ret < 0)
> + ret = -EIO;
> +out:
> + kfree(t_buf);
> +
> + return ret;
> +}
> +
> +/*
> + * Extract and export the numeric value of the energy scale attributes
> + */
> +static ssize_t papr_show_value(struct kobject *kobj,
> + struct kobj_attribute *kobj_attr,
> + char *buf)
> +{
> + struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr,
> +kobj_attr);
> + struct h_energy_scale_info_hdr *t_hdr;
> + struct energy_scale_attribute *t_esi;
> + char *t_buf;
> + int ret = 0;
> +
> + t_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
> + if (t_buf == NULL)
> + return -ENOMEM;
> +
> + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE,
> + pattr->id, virt_to_phys(t_buf),
> + MAX_BUF_SZ);
> +
> + if (ret != H_SUCCESS) {
> + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
> + goto out;
> + }
> +
> + t_hdr = (struct h_energy_scale_info_hdr *) t_buf;
> + t_esi = (struct energy_scale_attribute *)
> + (t_buf + be64_to_cpu(t_hdr->array_offset));
> +
> + ret = snprintf(buf, sizeof(t_esi->value), "%llu\n",
> +be64_to_cpu(t_esi->value));
> + if (ret < 0)
> + ret = -EIO;
> +out:
> + kfree(t_buf);
> +
> + return ret;
> +}
> +
> +/*
> + * Extract and export the value description in string format of the energy
> + * scale attributes
> + */
> +static ssize_t papr_show_value_desc(struct kobject *kobj,
> + struct kobj_attribute *kobj_attr,
> + char *buf)
> +{
> + struct papr_attr *pattr = container_of(kobj_attr, struct papr_attr,
> +kobj_attr);
> + struct h_energy_scale_info_hdr *t_hdr;
> + struct energy_scale_attribute *t_esi;
> + char *t_buf;
> + int ret = 0;
> +
> + t_buf = kmalloc(MAX_BUF_SZ, GFP_KERNEL);
> + if (t_buf == NULL)
> + return -ENOMEM;
> +
> + ret = plpar_hcall_norets(H_GET_ENERGY_SCALE_INFO, ESI_FLAGS_SINGLE,
> + pattr->id, virt_to_phys(t_buf),
> + MAX_BUF_SZ);
> +
> + if (ret != H_SUCCESS) {
> + pr_warn("hcall failed: H_GET_ENERGY_SCALE_INFO");
> + goto out;
> + }
> +
> + t_hdr = (struct h_energy_scale_info_hdr *) t_buf;
> + t_esi = (struct energy_scale_attribute *)
> + (t_buf +
[PATCH v4 1/1] powerpc/pseries: Interface to represent PAPR firmware attributes
Adds a generic interface to represent the energy and frequency related
PAPR attributes on the system using the new H_CALL
"H_GET_ENERGY_SCALE_INFO".
H_GET_EM_PARMS H_CALL was previously responsible for exporting this
information in the lparcfg, however the H_GET_EM_PARMS H_CALL
will be deprecated P10 onwards.
The H_GET_ENERGY_SCALE_INFO H_CALL is of the following call format:
hcall(
uint64 H_GET_ENERGY_SCALE_INFO, // Get energy scale info
uint64 flags, // Per the flag request
uint64 firstAttributeId,// The attribute id
uint64 bufferAddress, // Guest physical address of the output buffer
uint64 bufferSize // The size in bytes of the output buffer
);
This H_CALL can query either all the attributes at once with
firstAttributeId = 0, flags = 0 as well as query only one attribute
at a time with firstAttributeId = id, flags = 1.
The output buffer consists of the following
1. number of attributes - 8 bytes
2. array offset to the data location - 8 bytes
3. version info - 1 byte
4. A data array of size num attributes, which contains the following:
a. attribute ID - 8 bytes
b. attribute value in number - 8 bytes
c. attribute name in string - 64 bytes
d. attribute value in string - 64 bytes
The new H_CALL exports information in direct string value format, hence
a new interface has been introduced in
/sys/firmware/papr/energy_scale_info to export this information to
userspace in an extensible pass-through format.
The H_CALL returns the name, numeric value and string value (if exists)
The format of exposing the sysfs information is as follows:
/sys/firmware/papr/energy_scale_info/
|-- /
|-- desc
|-- value
|-- value_desc (if exists)
|-- /
|-- desc
|-- value
|-- value_desc (if exists)
...
The energy information that is exported is useful for userspace tools
such as powerpc-utils. Currently these tools infer the
"power_mode_data" value in the lparcfg, which in turn is obtained from
the to be deprecated H_GET_EM_PARMS H_CALL.
On future platforms, such userspace utilities will have to look at the
data returned from the new H_CALL being populated in this new sysfs
interface and report this information directly without the need of
interpretation.
Signed-off-by: Pratik R. Sampat
Reviewed-by: Gautham R. Shenoy
---
.../sysfs-firmware-papr-energy-scale-info | 26 ++
arch/powerpc/include/asm/hvcall.h | 24 +-
arch/powerpc/kvm/trace_hv.h | 1 +
arch/powerpc/platforms/pseries/Makefile | 3 +-
.../pseries/papr_platform_attributes.c| 331 ++
5 files changed, 383 insertions(+), 2 deletions(-)
create mode 100644
Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info
create mode 100644 arch/powerpc/platforms/pseries/papr_platform_attributes.c
diff --git a/Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info
b/Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info
new file mode 100644
index ..139a576c7c9d
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-papr-energy-scale-info
@@ -0,0 +1,26 @@
+What: /sys/firmware/papr/energy_scale_info
+Date: June 2021
+Contact: Linux for PowerPC mailing list
+Description: Directory hosting a set of platform attributes like
+ energy/frequency on Linux running as a PAPR guest.
+
+ Each file in a directory contains a platform
+ attribute hierarchy pertaining to performance/
+ energy-savings mode and processor frequency.
+
+What: /sys/firmware/papr/energy_scale_info/
+ /sys/firmware/papr/energy_scale_info//desc
+ /sys/firmware/papr/energy_scale_info//value
+ /sys/firmware/papr/energy_scale_info//value_desc
+Date: June 2021
+Contact: Linux for PowerPC mailing list
+Description: Energy, frequency attributes directory for POWERVM servers
+
+ This directory provides energy, frequency, folding information.
It
+ contains below sysfs attributes:
+
+ - desc: String description of the attribute
+
+ - value: Numeric value of attribute
+
+ - value_desc: String value of attribute
diff --git a/arch/powerpc/include/asm/hvcall.h
b/arch/powerpc/include/asm/hvcall.h
index e3b29eda8074..c91714ea6719 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -316,7 +316,8 @@
#define H_SCM_PERFORMANCE_STATS 0x418
#define H_RPT_INVALIDATE 0x448
#define H_SCM_FLUSH0x44C
-#define MAX_HCALL_OPCODE H_SCM_FLUSH
+#define H_GET_ENERGY_SCALE_INFO0x450
+#define MAX_HCALL_OPCODE H_GET_ENERGY_SCALE_INFO
/* Scope args for H_SCM_UNBIND_ALL */
#define H_UNBIND_SCOPE_ALL (0x1)
@@ -631,6 +632,27 @@ struct hv_gpci_request_buffer {
uint8_t bytes[HGPCI_MAX_DATA_BYTES];
} __packed;
