On Tue, Jan 2, 2018 at 2:42 PM, Sudeep Holla <sudeep.holla@xxxxxxx> wrote: > The performance protocol is intended for the performance management of > group(s) of device(s) that run in the same performance domain. It > includes even the CPUs. A performance domain is defined by a set of > devices that always have to run at the same performance level. > For example, a set of CPUs that share a voltage domain, and have a > common frequency control, is said to be in the same performance domain. > > The commands in this protocol provide functionality to describe the > protocol version, describe various attribute flags, set and get the > performance level of a domain. It also supports discovery of the list > of performance levels supported by a performance domain, and the > properties of each performance level. > > This patch adds basic support for the performance protocol. > > Cc: Arnd Bergmann <arnd@xxxxxxxx> > Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx> > --- > drivers/firmware/arm_scmi/Makefile | 2 +- > drivers/firmware/arm_scmi/common.h | 1 + > drivers/firmware/arm_scmi/perf.c | 527 +++++++++++++++++++++++++++++++++++++ > include/linux/scmi_protocol.h | 34 +++ > 4 files changed, 563 insertions(+), 1 deletion(-) [...] > diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c > new file mode 100644 > index 000000000000..a1f5cf136748 > --- /dev/null > +++ b/drivers/firmware/arm_scmi/perf.c > @@ -0,0 +1,527 @@ > +/* > + * System Control and Management Interface (SCMI) Performance Protocol > + * > + * Copyright (C) 2017 ARM Ltd. > + * > + * This program is free software; you can redistribute it and/or modify it > + * under the terms and conditions of the GNU General Public License, > + * version 2, as published by the Free Software Foundation. > + * > + * This program is distributed in the hope it will be useful, but WITHOUT > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for > + * more details. > + * > + * You should have received a copy of the GNU General Public License along > + * with this program. If not, see <http://www.gnu.org/licenses/>. > + */ > + > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/pm_opp.h> > +#include <linux/sort.h> > + > +#include "common.h" > + > +enum scmi_performance_protocol_cmd { > + PERF_DOMAIN_ATTRIBUTES = 0x3, > + PERF_DESCRIBE_LEVELS = 0x4, > + PERF_LIMITS_SET = 0x5, > + PERF_LIMITS_GET = 0x6, > + PERF_LEVEL_SET = 0x7, > + PERF_LEVEL_GET = 0x8, > + PERF_NOTIFY_LIMITS = 0x9, > + PERF_NOTIFY_LEVEL = 0xa, > +}; > + > +struct scmi_opp { > + u32 perf; > + u32 power; > + u32 trans_latency_us; > +}; > + > +struct scmi_msg_resp_perf_attributes { > + __le16 num_domains; > + __le16 flags; > +#define POWER_SCALE_IN_MILLIWATT(x) ((x) & BIT(0)) > + __le32 stats_addr_low; > + __le32 stats_addr_high; > + __le32 stats_size; > +}; > + > +struct scmi_msg_resp_perf_domain_attributes { > + __le32 flags; > +#define SUPPORTS_SET_LIMITS(x) ((x) & BIT(31)) > +#define SUPPORTS_SET_PERF_LVL(x) ((x) & BIT(30)) > +#define SUPPORTS_PERF_LIMIT_NOTIFY(x) ((x) & BIT(29)) > +#define SUPPORTS_PERF_LEVEL_NOTIFY(x) ((x) & BIT(28)) > + __le32 rate_limit_us; > + __le32 sustained_freq_khz; > + __le32 sustained_perf_level; > + u8 name[SCMI_MAX_STR_SIZE]; > +}; > + > +struct scmi_msg_perf_describe_levels { > + __le32 domain; > + __le32 level_index; > +}; > + > +struct scmi_perf_set_limits { > + __le32 domain; > + __le32 max_level; > + __le32 min_level; > +}; > + > +struct scmi_perf_get_limits { > + __le32 max_level; > + __le32 min_level; > +}; > + > +struct scmi_perf_set_level { > + __le32 domain; > + __le32 level; > +}; > + > +struct scmi_perf_notify_level_or_limits { > + __le32 domain; > + __le32 notify_enable; > +}; > + > +struct scmi_msg_resp_perf_describe_levels { > + __le16 num_returned; > + __le16 num_remaining; > + struct { > + __le32 perf_val; > + __le32 power; > + __le16 transition_latency_us; > + __le16 reserved; > + } opp[0]; > +}; > + > +struct perf_dom_info { > + bool set_limits; > + bool set_perf; > + bool perf_limit_notify; > + bool perf_level_notify; > + u32 opp_count; > + u32 sustained_freq_khz; > + u32 sustained_perf_level; > + u32 mult_factor; > + char name[SCMI_MAX_STR_SIZE]; > + struct scmi_opp opp[MAX_OPPS]; > +}; > + > +struct scmi_perf_info { > + int num_domains; > + bool power_scale_mw; > + u64 stats_addr; > + u32 stats_size; > + struct perf_dom_info *dom_info; > +}; > + > +static int scmi_perf_attributes_get(const struct scmi_handle *handle, > + struct scmi_perf_info *pi) > +{ > + int ret; > + struct scmi_xfer *t; > + struct scmi_msg_resp_perf_attributes *attr; > + > + ret = scmi_one_xfer_init(handle, PROTOCOL_ATTRIBUTES, > + SCMI_PROTOCOL_PERF, 0, sizeof(*attr), &t); > + if (ret) > + return ret; > + > + attr = t->rx.buf; > + > + ret = scmi_do_xfer(handle, t); > + if (!ret) { > + u16 flags = le16_to_cpu(attr->flags); > + > + pi->num_domains = le16_to_cpu(attr->num_domains); > + pi->power_scale_mw = POWER_SCALE_IN_MILLIWATT(flags); > + pi->stats_addr = le32_to_cpu(attr->stats_addr_low) | > + (u64)le32_to_cpu(attr->stats_addr_high) << 32; > + pi->stats_size = le32_to_cpu(attr->stats_size); > + } > + > + scmi_one_xfer_put(handle, t); > + return ret; > +} > + > +static int > +scmi_perf_domain_attributes_get(const struct scmi_handle *handle, u32 domain, > + struct perf_dom_info *dom_info) > +{ > + int ret; > + struct scmi_xfer *t; > + struct scmi_msg_resp_perf_domain_attributes *attr; > + > + ret = scmi_one_xfer_init(handle, PERF_DOMAIN_ATTRIBUTES, > + SCMI_PROTOCOL_PERF, sizeof(domain), > + sizeof(*attr), &t); > + if (ret) > + return ret; > + > + *(__le32 *)t->tx.buf = cpu_to_le32(domain); > + attr = t->rx.buf; > + > + ret = scmi_do_xfer(handle, t); > + if (!ret) { > + u32 flags = le32_to_cpu(attr->flags); > + > + dom_info->set_limits = SUPPORTS_SET_LIMITS(flags); > + dom_info->set_perf = SUPPORTS_SET_PERF_LVL(flags); > + dom_info->perf_limit_notify = SUPPORTS_PERF_LIMIT_NOTIFY(flags); > + dom_info->perf_level_notify = SUPPORTS_PERF_LEVEL_NOTIFY(flags); > + dom_info->sustained_freq_khz = > + le32_to_cpu(attr->sustained_freq_khz); > + dom_info->sustained_perf_level = > + le32_to_cpu(attr->sustained_perf_level); > + dom_info->mult_factor = (dom_info->sustained_freq_khz * 1000) / > + dom_info->sustained_perf_level; > + memcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE); > + } > + > + scmi_one_xfer_put(handle, t); > + return ret; > +} > + > +static int opp_cmp_func(const void *opp1, const void *opp2) > +{ > + const struct scmi_opp *t1 = opp1, *t2 = opp2; > + > + return t1->perf - t2->perf; > +} > + > +static int > +scmi_perf_describe_levels_get(const struct scmi_handle *handle, u32 domain, > + struct perf_dom_info *perf_dom) > +{ > + int ret, cnt; > + u32 tot_opp_cnt = 0; > + u16 num_returned, num_remaining; > + struct scmi_xfer *t; > + struct scmi_opp *opp; > + struct scmi_msg_perf_describe_levels *dom_info; > + struct scmi_msg_resp_perf_describe_levels *level_info; > + > + ret = scmi_one_xfer_init(handle, PERF_DESCRIBE_LEVELS, > + SCMI_PROTOCOL_PERF, sizeof(*dom_info), 0, &t); > + if (ret) > + return ret; > + > + dom_info = t->tx.buf; > + level_info = t->rx.buf; > + > + do { > + dom_info->domain = cpu_to_le32(domain); > + /* Set the number of OPPs to be skipped/already read */ > + dom_info->level_index = cpu_to_le32(tot_opp_cnt); > + > + ret = scmi_do_xfer(handle, t); > + if (ret) > + break; > + > + num_returned = le16_to_cpu(level_info->num_returned); > + num_remaining = le16_to_cpu(level_info->num_remaining); > + if (tot_opp_cnt + num_returned > MAX_OPPS) { > + dev_err(handle->dev, "No. of OPPs exceeded MAX_OPPS"); > + break; > + } > + > + opp = &perf_dom->opp[tot_opp_cnt]; > + for (cnt = 0; cnt < num_returned; cnt++, opp++) { > + opp->perf = le32_to_cpu(level_info->opp[cnt].perf_val); > + opp->power = le32_to_cpu(level_info->opp[cnt].power); > + opp->trans_latency_us = le16_to_cpu( > + level_info->opp[cnt].transition_latency_us); > + > + dev_dbg(handle->dev, "Level %d Power %d Latency %dus\n", > + opp->perf, opp->power, opp->trans_latency_us); > + } > + > + tot_opp_cnt += num_returned; > + /* > + * check for both returned and remaining to avoid infinite > + * loop due to buggy firmware > + */ > + } while (num_returned && num_remaining); > + > + perf_dom->opp_count = tot_opp_cnt; > + scmi_one_xfer_put(handle, t); > + > + sort(perf_dom->opp, tot_opp_cnt, sizeof(*opp), opp_cmp_func, NULL); > + return ret; > +} > + > +static int scmi_perf_limits_set(const struct scmi_handle *handle, u32 domain, > + u32 max_perf, u32 min_perf) > +{ > + int ret; > + struct scmi_xfer *t; > + struct scmi_perf_set_limits *limits; > + > + ret = scmi_one_xfer_init(handle, PERF_LIMITS_SET, SCMI_PROTOCOL_PERF, > + sizeof(*limits), 0, &t); > + if (ret) > + return ret; > + > + limits = t->tx.buf; > + limits->domain = cpu_to_le32(domain); > + limits->max_level = cpu_to_le32(max_perf); > + limits->min_level = cpu_to_le32(min_perf); > + > + ret = scmi_do_xfer(handle, t); > + > + scmi_one_xfer_put(handle, t); > + return ret; > +} > + > +static int scmi_perf_limits_get(const struct scmi_handle *handle, u32 domain, > + u32 *max_perf, u32 *min_perf) > +{ > + int ret; > + struct scmi_xfer *t; > + struct scmi_perf_get_limits *limits; > + > + ret = scmi_one_xfer_init(handle, PERF_LIMITS_GET, SCMI_PROTOCOL_PERF, > + sizeof(__le32), 0, &t); > + if (ret) > + return ret; > + > + *(__le32 *)t->tx.buf = cpu_to_le32(domain); > + > + ret = scmi_do_xfer(handle, t); > + if (!ret) { > + limits = t->rx.buf; > + > + *max_perf = le32_to_cpu(limits->max_level); > + *min_perf = le32_to_cpu(limits->min_level); > + } > + > + scmi_one_xfer_put(handle, t); > + return ret; > +} > + > +static int > +scmi_perf_level_set(const struct scmi_handle *handle, u32 domain, u32 level) > +{ > + int ret; > + struct scmi_xfer *t; > + struct scmi_perf_set_level *lvl; > + > + ret = scmi_one_xfer_init(handle, PERF_LEVEL_SET, SCMI_PROTOCOL_PERF, > + sizeof(*lvl), 0, &t); > + if (ret) > + return ret; > + > + lvl = t->tx.buf; > + lvl->domain = cpu_to_le32(domain); > + lvl->level = cpu_to_le32(level); > + > + ret = scmi_do_xfer(handle, t); > + > + scmi_one_xfer_put(handle, t); > + return ret; > +} > + > +static int > +scmi_perf_level_get(const struct scmi_handle *handle, u32 domain, u32 *level) > +{ > + int ret; > + struct scmi_xfer *t; > + > + ret = scmi_one_xfer_init(handle, PERF_LEVEL_GET, SCMI_PROTOCOL_PERF, > + sizeof(u32), sizeof(u32), &t); > + if (ret) > + return ret; > + > + *(__le32 *)t->tx.buf = cpu_to_le32(domain); > + > + ret = scmi_do_xfer(handle, t); > + if (!ret) > + *level = le32_to_cpu(*(__le32 *)t->rx.buf); > + > + scmi_one_xfer_put(handle, t); > + return ret; > +} > + > +static int __scmi_perf_notify_enable(const struct scmi_handle *handle, u32 cmd, > + u32 domain, bool enable) > +{ > + int ret; > + struct scmi_xfer *t; > + struct scmi_perf_notify_level_or_limits *notify; > + > + ret = scmi_one_xfer_init(handle, cmd, SCMI_PROTOCOL_PERF, > + sizeof(*notify), 0, &t); > + if (ret) > + return ret; > + > + notify = t->tx.buf; > + notify->domain = cpu_to_le32(domain); > + notify->notify_enable = cpu_to_le32(enable & BIT(0)); > + > + ret = scmi_do_xfer(handle, t); > + > + scmi_one_xfer_put(handle, t); > + return ret; > +} > + > +static int scmi_perf_limits_notify_enable(const struct scmi_handle *handle, > + u32 domain, bool enable) > +{ > + return __scmi_perf_notify_enable(handle, PERF_NOTIFY_LIMITS, > + domain, enable); > +} > + > +static int scmi_perf_level_notify_enable(const struct scmi_handle *handle, > + u32 domain, bool enable) > +{ > + return __scmi_perf_notify_enable(handle, PERF_NOTIFY_LEVEL, > + domain, enable); > +} > + Do you have any support to correctly handle notifications without errors/warnings? It looks like this two functions are accessible to some user through perf_ops. But are you sure that notifications will be correctly handled by transport, mailbox framework and scmi protocol? The reason I ask is that it looks like it's better to return -EOPNOTSUPP or -ENODEV, maybe -EINVAL here. When you add notifications support you can allow these operations when it's safe to do it. [..] Best regards, Alexey Klimov -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
