linux/drivers/firmware/arm_scmi/base.c
Cristian Marussi 72a5eb9d9c firmware: arm_scmi: Remove fixed size fields from reports/scmi_event_header
Event reports are used to convey information describing events to the
registered user-callbacks: they are necessarily derived from the underlying
raw SCMI events' messages but they are not meant to expose or directly
mirror any of those messages data layout, which belong to the protocol
layer.

Using fixed size types for report fields, mirroring messages structure,
is at odd with this: get rid of them using more generic, equivalent,
typing.

Substitute scmi_event_header fixed size fields with generic types too and
shuffle around fields definitions to minimize implicit padding while
adapting involved functions.

Link: https://lore.kernel.org/r/20200710133919.39792-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-13 09:40:21 +01:00

366 lines
9.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* System Control and Management Interface (SCMI) Base Protocol
*
* Copyright (C) 2018 ARM Ltd.
*/
#define pr_fmt(fmt) "SCMI Notifications BASE - " fmt
#include <linux/scmi_protocol.h>
#include "common.h"
#include "notify.h"
#define SCMI_BASE_NUM_SOURCES 1
#define SCMI_BASE_MAX_CMD_ERR_COUNT 1024
enum scmi_base_protocol_cmd {
BASE_DISCOVER_VENDOR = 0x3,
BASE_DISCOVER_SUB_VENDOR = 0x4,
BASE_DISCOVER_IMPLEMENT_VERSION = 0x5,
BASE_DISCOVER_LIST_PROTOCOLS = 0x6,
BASE_DISCOVER_AGENT = 0x7,
BASE_NOTIFY_ERRORS = 0x8,
BASE_SET_DEVICE_PERMISSIONS = 0x9,
BASE_SET_PROTOCOL_PERMISSIONS = 0xa,
BASE_RESET_AGENT_CONFIGURATION = 0xb,
};
struct scmi_msg_resp_base_attributes {
u8 num_protocols;
u8 num_agents;
__le16 reserved;
};
struct scmi_msg_base_error_notify {
__le32 event_control;
#define BASE_TP_NOTIFY_ALL BIT(0)
};
struct scmi_base_error_notify_payld {
__le32 agent_id;
__le32 error_status;
#define IS_FATAL_ERROR(x) ((x) & BIT(31))
#define ERROR_CMD_COUNT(x) FIELD_GET(GENMASK(9, 0), (x))
__le64 msg_reports[SCMI_BASE_MAX_CMD_ERR_COUNT];
};
/**
* scmi_base_attributes_get() - gets the implementation details
* that are associated with the base protocol.
*
* @handle: SCMI entity handle
*
* Return: 0 on success, else appropriate SCMI error.
*/
static int scmi_base_attributes_get(const struct scmi_handle *handle)
{
int ret;
struct scmi_xfer *t;
struct scmi_msg_resp_base_attributes *attr_info;
struct scmi_revision_info *rev = handle->version;
ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
SCMI_PROTOCOL_BASE, 0, sizeof(*attr_info), &t);
if (ret)
return ret;
ret = scmi_do_xfer(handle, t);
if (!ret) {
attr_info = t->rx.buf;
rev->num_protocols = attr_info->num_protocols;
rev->num_agents = attr_info->num_agents;
}
scmi_xfer_put(handle, t);
return ret;
}
/**
* scmi_base_vendor_id_get() - gets vendor/subvendor identifier ASCII string.
*
* @handle: SCMI entity handle
* @sub_vendor: specify true if sub-vendor ID is needed
*
* Return: 0 on success, else appropriate SCMI error.
*/
static int
scmi_base_vendor_id_get(const struct scmi_handle *handle, bool sub_vendor)
{
u8 cmd;
int ret, size;
char *vendor_id;
struct scmi_xfer *t;
struct scmi_revision_info *rev = handle->version;
if (sub_vendor) {
cmd = BASE_DISCOVER_SUB_VENDOR;
vendor_id = rev->sub_vendor_id;
size = ARRAY_SIZE(rev->sub_vendor_id);
} else {
cmd = BASE_DISCOVER_VENDOR;
vendor_id = rev->vendor_id;
size = ARRAY_SIZE(rev->vendor_id);
}
ret = scmi_xfer_get_init(handle, cmd, SCMI_PROTOCOL_BASE, 0, size, &t);
if (ret)
return ret;
ret = scmi_do_xfer(handle, t);
if (!ret)
memcpy(vendor_id, t->rx.buf, size);
scmi_xfer_put(handle, t);
return ret;
}
/**
* scmi_base_implementation_version_get() - gets a vendor-specific
* implementation 32-bit version. The format of the version number is
* vendor-specific
*
* @handle: SCMI entity handle
*
* Return: 0 on success, else appropriate SCMI error.
*/
static int
scmi_base_implementation_version_get(const struct scmi_handle *handle)
{
int ret;
__le32 *impl_ver;
struct scmi_xfer *t;
struct scmi_revision_info *rev = handle->version;
ret = scmi_xfer_get_init(handle, BASE_DISCOVER_IMPLEMENT_VERSION,
SCMI_PROTOCOL_BASE, 0, sizeof(*impl_ver), &t);
if (ret)
return ret;
ret = scmi_do_xfer(handle, t);
if (!ret) {
impl_ver = t->rx.buf;
rev->impl_ver = le32_to_cpu(*impl_ver);
}
scmi_xfer_put(handle, t);
return ret;
}
/**
* scmi_base_implementation_list_get() - gets the list of protocols it is
* OSPM is allowed to access
*
* @handle: SCMI entity handle
* @protocols_imp: pointer to hold the list of protocol identifiers
*
* Return: 0 on success, else appropriate SCMI error.
*/
static int scmi_base_implementation_list_get(const struct scmi_handle *handle,
u8 *protocols_imp)
{
u8 *list;
int ret, loop;
struct scmi_xfer *t;
__le32 *num_skip, *num_ret;
u32 tot_num_ret = 0, loop_num_ret;
struct device *dev = handle->dev;
ret = scmi_xfer_get_init(handle, BASE_DISCOVER_LIST_PROTOCOLS,
SCMI_PROTOCOL_BASE, sizeof(*num_skip), 0, &t);
if (ret)
return ret;
num_skip = t->tx.buf;
num_ret = t->rx.buf;
list = t->rx.buf + sizeof(*num_ret);
do {
/* Set the number of protocols to be skipped/already read */
*num_skip = cpu_to_le32(tot_num_ret);
ret = scmi_do_xfer(handle, t);
if (ret)
break;
loop_num_ret = le32_to_cpu(*num_ret);
if (tot_num_ret + loop_num_ret > MAX_PROTOCOLS_IMP) {
dev_err(dev, "No. of Protocol > MAX_PROTOCOLS_IMP");
break;
}
for (loop = 0; loop < loop_num_ret; loop++)
protocols_imp[tot_num_ret + loop] = *(list + loop);
tot_num_ret += loop_num_ret;
} while (loop_num_ret);
scmi_xfer_put(handle, t);
return ret;
}
/**
* scmi_base_discover_agent_get() - discover the name of an agent
*
* @handle: SCMI entity handle
* @id: Agent identifier
* @name: Agent identifier ASCII string
*
* An agent id of 0 is reserved to identify the platform itself.
* Generally operating system is represented as "OSPM"
*
* Return: 0 on success, else appropriate SCMI error.
*/
static int scmi_base_discover_agent_get(const struct scmi_handle *handle,
int id, char *name)
{
int ret;
struct scmi_xfer *t;
ret = scmi_xfer_get_init(handle, BASE_DISCOVER_AGENT,
SCMI_PROTOCOL_BASE, sizeof(__le32),
SCMI_MAX_STR_SIZE, &t);
if (ret)
return ret;
put_unaligned_le32(id, t->tx.buf);
ret = scmi_do_xfer(handle, t);
if (!ret)
strlcpy(name, t->rx.buf, SCMI_MAX_STR_SIZE);
scmi_xfer_put(handle, t);
return ret;
}
static int scmi_base_error_notify(const struct scmi_handle *handle, bool enable)
{
int ret;
u32 evt_cntl = enable ? BASE_TP_NOTIFY_ALL : 0;
struct scmi_xfer *t;
struct scmi_msg_base_error_notify *cfg;
ret = scmi_xfer_get_init(handle, BASE_NOTIFY_ERRORS,
SCMI_PROTOCOL_BASE, sizeof(*cfg), 0, &t);
if (ret)
return ret;
cfg = t->tx.buf;
cfg->event_control = cpu_to_le32(evt_cntl);
ret = scmi_do_xfer(handle, t);
scmi_xfer_put(handle, t);
return ret;
}
static int scmi_base_set_notify_enabled(const struct scmi_handle *handle,
u8 evt_id, u32 src_id, bool enable)
{
int ret;
ret = scmi_base_error_notify(handle, enable);
if (ret)
pr_debug("FAIL_ENABLED - evt[%X] ret:%d\n", evt_id, ret);
return ret;
}
static void *scmi_base_fill_custom_report(const struct scmi_handle *handle,
u8 evt_id, ktime_t timestamp,
const void *payld, size_t payld_sz,
void *report, u32 *src_id)
{
int i;
const struct scmi_base_error_notify_payld *p = payld;
struct scmi_base_error_report *r = report;
/*
* BaseError notification payload is variable in size but
* up to a maximum length determined by the struct ponted by p.
* Instead payld_sz is the effective length of this notification
* payload so cannot be greater of the maximum allowed size as
* pointed by p.
*/
if (evt_id != SCMI_EVENT_BASE_ERROR_EVENT || sizeof(*p) < payld_sz)
return NULL;
r->timestamp = timestamp;
r->agent_id = le32_to_cpu(p->agent_id);
r->fatal = IS_FATAL_ERROR(le32_to_cpu(p->error_status));
r->cmd_count = ERROR_CMD_COUNT(le32_to_cpu(p->error_status));
for (i = 0; i < r->cmd_count; i++)
r->reports[i] = le64_to_cpu(p->msg_reports[i]);
*src_id = 0;
return r;
}
static const struct scmi_event base_events[] = {
{
.id = SCMI_EVENT_BASE_ERROR_EVENT,
.max_payld_sz = sizeof(struct scmi_base_error_notify_payld),
.max_report_sz = sizeof(struct scmi_base_error_report) +
SCMI_BASE_MAX_CMD_ERR_COUNT * sizeof(u64),
},
};
static const struct scmi_event_ops base_event_ops = {
.set_notify_enabled = scmi_base_set_notify_enabled,
.fill_custom_report = scmi_base_fill_custom_report,
};
int scmi_base_protocol_init(struct scmi_handle *h)
{
int id, ret;
u8 *prot_imp;
u32 version;
char name[SCMI_MAX_STR_SIZE];
const struct scmi_handle *handle = h;
struct device *dev = handle->dev;
struct scmi_revision_info *rev = handle->version;
ret = scmi_version_get(handle, SCMI_PROTOCOL_BASE, &version);
if (ret)
return ret;
prot_imp = devm_kcalloc(dev, MAX_PROTOCOLS_IMP, sizeof(u8), GFP_KERNEL);
if (!prot_imp)
return -ENOMEM;
rev->major_ver = PROTOCOL_REV_MAJOR(version),
rev->minor_ver = PROTOCOL_REV_MINOR(version);
scmi_base_attributes_get(handle);
scmi_base_vendor_id_get(handle, false);
scmi_base_vendor_id_get(handle, true);
scmi_base_implementation_version_get(handle);
scmi_base_implementation_list_get(handle, prot_imp);
scmi_setup_protocol_implemented(handle, prot_imp);
dev_info(dev, "SCMI Protocol v%d.%d '%s:%s' Firmware version 0x%x\n",
rev->major_ver, rev->minor_ver, rev->vendor_id,
rev->sub_vendor_id, rev->impl_ver);
dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols,
rev->num_agents);
scmi_register_protocol_events(handle, SCMI_PROTOCOL_BASE,
(4 * SCMI_PROTO_QUEUE_SZ),
&base_event_ops, base_events,
ARRAY_SIZE(base_events),
SCMI_BASE_NUM_SOURCES);
for (id = 0; id < rev->num_agents; id++) {
scmi_base_discover_agent_get(handle, id, name);
dev_dbg(dev, "Agent %d: %s\n", id, name);
}
return 0;
}