linux/arch/powerpc/platforms/pseries/firmware.c
Pratik R. Sampat 3c14b73454 powerpc/pseries: Interface to represent PAPR firmware attributes
Adds a syscall 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
);
As specified in PAPR+ v2.11, section 14.14.3.

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 so that the firmware can add new values without the need for
the kernel to be changed.

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/
   |-- <id>/
     |-- desc
     |-- value
     |-- value_desc (if exists)
   |-- <id>/
     |-- 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 <psampat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220217105321.52941-2-psampat@linux.ibm.com
2022-03-08 00:05:00 +11:00

190 lines
5.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* pSeries firmware setup code.
*
* Portions from arch/powerpc/platforms/pseries/setup.c:
* Copyright (C) 1995 Linus Torvalds
* Adapted from 'alpha' version by Gary Thomas
* Modified by Cort Dougan (cort@cs.nmt.edu)
* Modified by PPC64 Team, IBM Corp
*
* Portions from arch/powerpc/kernel/firmware.c
* Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
* Modifications for ppc64:
* Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
* Copyright (C) 2005 Stephen Rothwell, IBM Corporation
*
* Copyright 2006 IBM Corporation.
*/
#include <linux/of_fdt.h>
#include <asm/firmware.h>
#include <asm/prom.h>
#include <asm/udbg.h>
#include <asm/svm.h>
#include "pseries.h"
struct hypertas_fw_feature {
unsigned long val;
char * name;
};
/*
* The names in this table match names in rtas/ibm,hypertas-functions. If the
* entry ends in a '*', only upto the '*' is matched. Otherwise the entire
* string must match.
*/
static __initdata struct hypertas_fw_feature
hypertas_fw_features_table[] = {
{FW_FEATURE_PFT, "hcall-pft"},
{FW_FEATURE_TCE, "hcall-tce"},
{FW_FEATURE_SPRG0, "hcall-sprg0"},
{FW_FEATURE_DABR, "hcall-dabr"},
{FW_FEATURE_COPY, "hcall-copy"},
{FW_FEATURE_ASR, "hcall-asr"},
{FW_FEATURE_DEBUG, "hcall-debug"},
{FW_FEATURE_PERF, "hcall-perf"},
{FW_FEATURE_DUMP, "hcall-dump"},
{FW_FEATURE_INTERRUPT, "hcall-interrupt"},
{FW_FEATURE_MIGRATE, "hcall-migrate"},
{FW_FEATURE_PERFMON, "hcall-perfmon"},
{FW_FEATURE_CRQ, "hcall-crq"},
{FW_FEATURE_VIO, "hcall-vio"},
{FW_FEATURE_RDMA, "hcall-rdma"},
{FW_FEATURE_LLAN, "hcall-lLAN"},
{FW_FEATURE_BULK_REMOVE, "hcall-bulk"},
{FW_FEATURE_XDABR, "hcall-xdabr"},
{FW_FEATURE_PUT_TCE_IND | FW_FEATURE_STUFF_TCE,
"hcall-multi-tce"},
{FW_FEATURE_SPLPAR, "hcall-splpar"},
{FW_FEATURE_VPHN, "hcall-vphn"},
{FW_FEATURE_SET_MODE, "hcall-set-mode"},
{FW_FEATURE_BEST_ENERGY, "hcall-best-energy-1*"},
{FW_FEATURE_HPT_RESIZE, "hcall-hpt-resize"},
{FW_FEATURE_BLOCK_REMOVE, "hcall-block-remove"},
{FW_FEATURE_PAPR_SCM, "hcall-scm"},
{FW_FEATURE_RPT_INVALIDATE, "hcall-rpt-invalidate"},
{FW_FEATURE_ENERGY_SCALE_INFO, "hcall-energy-scale-info"},
};
/* Build up the firmware features bitmask using the contents of
* device-tree/ibm,hypertas-functions. Ultimately this functionality may
* be moved into prom.c prom_init().
*/
static void __init fw_hypertas_feature_init(const char *hypertas,
unsigned long len)
{
const char *s;
int i;
pr_debug(" -> fw_hypertas_feature_init()\n");
for (s = hypertas; s < hypertas + len; s += strlen(s) + 1) {
for (i = 0; i < ARRAY_SIZE(hypertas_fw_features_table); i++) {
const char *name = hypertas_fw_features_table[i].name;
size_t size;
/*
* If there is a '*' at the end of name, only check
* upto there
*/
size = strlen(name);
if (size && name[size - 1] == '*') {
if (strncmp(name, s, size - 1))
continue;
} else if (strcmp(name, s))
continue;
/* we have a match */
powerpc_firmware_features |=
hypertas_fw_features_table[i].val;
break;
}
}
if (is_secure_guest() &&
(powerpc_firmware_features & FW_FEATURE_PUT_TCE_IND)) {
powerpc_firmware_features &= ~FW_FEATURE_PUT_TCE_IND;
pr_debug("SVM: disabling PUT_TCE_IND firmware feature\n");
}
pr_debug(" <- fw_hypertas_feature_init()\n");
}
struct vec5_fw_feature {
unsigned long val;
unsigned int feature;
};
static __initdata struct vec5_fw_feature
vec5_fw_features_table[] = {
{FW_FEATURE_FORM1_AFFINITY, OV5_FORM1_AFFINITY},
{FW_FEATURE_PRRN, OV5_PRRN},
{FW_FEATURE_DRMEM_V2, OV5_DRMEM_V2},
{FW_FEATURE_DRC_INFO, OV5_DRC_INFO},
{FW_FEATURE_FORM2_AFFINITY, OV5_FORM2_AFFINITY},
};
static void __init fw_vec5_feature_init(const char *vec5, unsigned long len)
{
unsigned int index, feat;
int i;
pr_debug(" -> fw_vec5_feature_init()\n");
for (i = 0; i < ARRAY_SIZE(vec5_fw_features_table); i++) {
index = OV5_INDX(vec5_fw_features_table[i].feature);
feat = OV5_FEAT(vec5_fw_features_table[i].feature);
if (index < len && (vec5[index] & feat))
powerpc_firmware_features |=
vec5_fw_features_table[i].val;
}
pr_debug(" <- fw_vec5_feature_init()\n");
}
/*
* Called very early, MMU is off, device-tree isn't unflattened
*/
static int __init probe_fw_features(unsigned long node, const char *uname, int
depth, void *data)
{
const char *prop;
int len;
static int hypertas_found;
static int vec5_found;
if (depth != 1)
return 0;
if (!strcmp(uname, "rtas") || !strcmp(uname, "rtas@0")) {
prop = of_get_flat_dt_prop(node, "ibm,hypertas-functions",
&len);
if (prop) {
powerpc_firmware_features |= FW_FEATURE_LPAR;
fw_hypertas_feature_init(prop, len);
}
hypertas_found = 1;
}
if (!strcmp(uname, "chosen")) {
prop = of_get_flat_dt_prop(node, "ibm,architecture-vec-5",
&len);
if (prop)
fw_vec5_feature_init(prop, len);
vec5_found = 1;
}
return hypertas_found && vec5_found;
}
void __init pseries_probe_fw_features(void)
{
of_scan_flat_dt(probe_fw_features, NULL);
}