| Message ID | 20220124171705.10432-10-Jonathan.Cameron@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | CXl 2.0 emulation Support | expand |
Jonathan Cameron <Jonathan.Cameron@huawei.com> writes: > From: Ben Widawsky <ben.widawsky@intel.com> > > Per spec, timestamp appears to be a free-running counter from a value > set by the host via the Set Timestamp command (0301h). There are > references to the epoch, which seem like a red herring. Therefore, the > implementation implements the timestamp as freerunning counter from the > last value that was issued by the Set Timestamp command. > > Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > --- > hw/cxl/cxl-mailbox-utils.c | 53 +++++++++++++++++++++++++++++++++++++ > include/hw/cxl/cxl_device.h | 6 +++++ > 2 files changed, 59 insertions(+) > > diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c > index 1a87846356..cea4b2a59c 100644 > --- a/hw/cxl/cxl-mailbox-utils.c > +++ b/hw/cxl/cxl-mailbox-utils.c > @@ -43,6 +43,9 @@ enum { > #define CLEAR_RECORDS 0x1 > #define GET_INTERRUPT_POLICY 0x2 > #define SET_INTERRUPT_POLICY 0x3 > + TIMESTAMP = 0x03, > + #define GET 0x0 > + #define SET 0x1 > }; > > /* 8.2.8.4.5.1 Command Return Codes */ > @@ -117,8 +120,11 @@ define_mailbox_handler_zeroed(EVENTS_GET_RECORDS, 0x20); > define_mailbox_handler_nop(EVENTS_CLEAR_RECORDS); > define_mailbox_handler_zeroed(EVENTS_GET_INTERRUPT_POLICY, 4); > define_mailbox_handler_nop(EVENTS_SET_INTERRUPT_POLICY); > +declare_mailbox_handler(TIMESTAMP_GET); > +declare_mailbox_handler(TIMESTAMP_SET); > > #define IMMEDIATE_CONFIG_CHANGE (1 << 1) > +#define IMMEDIATE_POLICY_CHANGE (1 << 3) > #define IMMEDIATE_LOG_CHANGE (1 << 4) > > #define CXL_CMD(s, c, in, cel_effect) \ > @@ -129,10 +135,57 @@ static struct cxl_cmd cxl_cmd_set[256][256] = { > CXL_CMD(EVENTS, CLEAR_RECORDS, ~0, IMMEDIATE_LOG_CHANGE), > CXL_CMD(EVENTS, GET_INTERRUPT_POLICY, 0, 0), > CXL_CMD(EVENTS, SET_INTERRUPT_POLICY, 4, IMMEDIATE_CONFIG_CHANGE), > + CXL_CMD(TIMESTAMP, GET, 0, 0), > + CXL_CMD(TIMESTAMP, SET, 8, IMMEDIATE_POLICY_CHANGE), > }; > > #undef CXL_CMD > > +/* > + * 8.2.9.3.1 > + */ > +define_mailbox_handler(TIMESTAMP_GET) > +{ > + struct timespec ts; > + uint64_t delta; > + > + if (!cxl_dstate->timestamp.set) { > + *(uint64_t *)cmd->payload = 0; > + goto done; > + } > + > + /* First find the delta from the last time the host set the time. */ > + clock_gettime(CLOCK_REALTIME, &ts); Could you consider using qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL)? Otherwise by introducing a dependency on real time you'll loose the ability to get deterministic execution via icount. > + delta = (ts.tv_sec * NANOSECONDS_PER_SECOND + ts.tv_nsec) - > + cxl_dstate->timestamp.last_set; > + > + /* Then adjust the actual time */ > + stq_le_p(cmd->payload, cxl_dstate->timestamp.host_set + delta); > + > +done: > + *len = 8; > + return CXL_MBOX_SUCCESS; > +} > + > +/* > + * 8.2.9.3.2 > + */ > +define_mailbox_handler(TIMESTAMP_SET) > +{ > + struct timespec ts; > + > + clock_gettime(CLOCK_REALTIME, &ts); > + > + cxl_dstate->timestamp.set = true; > + cxl_dstate->timestamp.last_set = > + ts.tv_sec * NANOSECONDS_PER_SECOND + ts.tv_nsec; > + > + cxl_dstate->timestamp.host_set = le64_to_cpu(*(uint64_t *)cmd->payload); > + > + *len = 0; > + return CXL_MBOX_SUCCESS; > +} > + > QemuUUID cel_uuid; > > void cxl_process_mailbox(CXLDeviceState *cxl_dstate) > diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h > index f88f844cb6..3dde7fb1fb 100644 > --- a/include/hw/cxl/cxl_device.h > +++ b/include/hw/cxl/cxl_device.h > @@ -114,6 +114,12 @@ typedef struct cxl_device_state { > size_t cel_size; > }; > > + struct { > + bool set; > + uint64_t last_set; > + uint64_t host_set; > + } timestamp; > + > /* memory region for persistent memory, HDM */ > uint64_t pmem_size; > } CXLDeviceState;
On Thu, 27 Jan 2022 11:50:08 +0000 Alex Bennée <alex.bennee@linaro.org> wrote: > Jonathan Cameron <Jonathan.Cameron@huawei.com> writes: > > > From: Ben Widawsky <ben.widawsky@intel.com> > > > > Per spec, timestamp appears to be a free-running counter from a value > > set by the host via the Set Timestamp command (0301h). There are > > references to the epoch, which seem like a red herring. Therefore, the > > implementation implements the timestamp as freerunning counter from the > > last value that was issued by the Set Timestamp command. > > > > Signed-off-by: Ben Widawsky <ben.widawsky@intel.com> > > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > --- > > hw/cxl/cxl-mailbox-utils.c | 53 +++++++++++++++++++++++++++++++++++++ > > include/hw/cxl/cxl_device.h | 6 +++++ > > 2 files changed, 59 insertions(+) > > > > diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c > > index 1a87846356..cea4b2a59c 100644 > > --- a/hw/cxl/cxl-mailbox-utils.c > > +++ b/hw/cxl/cxl-mailbox-utils.c > > @@ -43,6 +43,9 @@ enum { > > #define CLEAR_RECORDS 0x1 > > #define GET_INTERRUPT_POLICY 0x2 > > #define SET_INTERRUPT_POLICY 0x3 > > + TIMESTAMP = 0x03, > > + #define GET 0x0 > > + #define SET 0x1 > > }; > > > > /* 8.2.8.4.5.1 Command Return Codes */ > > @@ -117,8 +120,11 @@ define_mailbox_handler_zeroed(EVENTS_GET_RECORDS, 0x20); > > define_mailbox_handler_nop(EVENTS_CLEAR_RECORDS); > > define_mailbox_handler_zeroed(EVENTS_GET_INTERRUPT_POLICY, 4); > > define_mailbox_handler_nop(EVENTS_SET_INTERRUPT_POLICY); > > +declare_mailbox_handler(TIMESTAMP_GET); > > +declare_mailbox_handler(TIMESTAMP_SET); > > > > #define IMMEDIATE_CONFIG_CHANGE (1 << 1) > > +#define IMMEDIATE_POLICY_CHANGE (1 << 3) > > #define IMMEDIATE_LOG_CHANGE (1 << 4) > > > > #define CXL_CMD(s, c, in, cel_effect) \ > > @@ -129,10 +135,57 @@ static struct cxl_cmd cxl_cmd_set[256][256] = { > > CXL_CMD(EVENTS, CLEAR_RECORDS, ~0, IMMEDIATE_LOG_CHANGE), > > CXL_CMD(EVENTS, GET_INTERRUPT_POLICY, 0, 0), > > CXL_CMD(EVENTS, SET_INTERRUPT_POLICY, 4, IMMEDIATE_CONFIG_CHANGE), > > + CXL_CMD(TIMESTAMP, GET, 0, 0), > > + CXL_CMD(TIMESTAMP, SET, 8, IMMEDIATE_POLICY_CHANGE), > > }; > > > > #undef CXL_CMD > > > > +/* > > + * 8.2.9.3.1 > > + */ > > +define_mailbox_handler(TIMESTAMP_GET) > > +{ > > + struct timespec ts; > > + uint64_t delta; > > + > > + if (!cxl_dstate->timestamp.set) { > > + *(uint64_t *)cmd->payload = 0; > > + goto done; > > + } > > + > > + /* First find the delta from the last time the host set the time. */ > > + clock_gettime(CLOCK_REALTIME, &ts); > > Could you consider using qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL)? > Otherwise by introducing a dependency on real time you'll loose the > ability to get deterministic execution via icount. I don't have a strong opinion either way, so Ill go with qemu_clock_get_ns() and see if any comments on it in v5. I've also updated the commit message as the catch all errata which was F4 included a clarification that the timestamp was as implemented here. Thanks, Jonathan
diff --git a/hw/cxl/cxl-mailbox-utils.c b/hw/cxl/cxl-mailbox-utils.c index 1a87846356..cea4b2a59c 100644 --- a/hw/cxl/cxl-mailbox-utils.c +++ b/hw/cxl/cxl-mailbox-utils.c @@ -43,6 +43,9 @@ enum { #define CLEAR_RECORDS 0x1 #define GET_INTERRUPT_POLICY 0x2 #define SET_INTERRUPT_POLICY 0x3 + TIMESTAMP = 0x03, + #define GET 0x0 + #define SET 0x1 }; /* 8.2.8.4.5.1 Command Return Codes */ @@ -117,8 +120,11 @@ define_mailbox_handler_zeroed(EVENTS_GET_RECORDS, 0x20); define_mailbox_handler_nop(EVENTS_CLEAR_RECORDS); define_mailbox_handler_zeroed(EVENTS_GET_INTERRUPT_POLICY, 4); define_mailbox_handler_nop(EVENTS_SET_INTERRUPT_POLICY); +declare_mailbox_handler(TIMESTAMP_GET); +declare_mailbox_handler(TIMESTAMP_SET); #define IMMEDIATE_CONFIG_CHANGE (1 << 1) +#define IMMEDIATE_POLICY_CHANGE (1 << 3) #define IMMEDIATE_LOG_CHANGE (1 << 4) #define CXL_CMD(s, c, in, cel_effect) \ @@ -129,10 +135,57 @@ static struct cxl_cmd cxl_cmd_set[256][256] = { CXL_CMD(EVENTS, CLEAR_RECORDS, ~0, IMMEDIATE_LOG_CHANGE), CXL_CMD(EVENTS, GET_INTERRUPT_POLICY, 0, 0), CXL_CMD(EVENTS, SET_INTERRUPT_POLICY, 4, IMMEDIATE_CONFIG_CHANGE), + CXL_CMD(TIMESTAMP, GET, 0, 0), + CXL_CMD(TIMESTAMP, SET, 8, IMMEDIATE_POLICY_CHANGE), }; #undef CXL_CMD +/* + * 8.2.9.3.1 + */ +define_mailbox_handler(TIMESTAMP_GET) +{ + struct timespec ts; + uint64_t delta; + + if (!cxl_dstate->timestamp.set) { + *(uint64_t *)cmd->payload = 0; + goto done; + } + + /* First find the delta from the last time the host set the time. */ + clock_gettime(CLOCK_REALTIME, &ts); + delta = (ts.tv_sec * NANOSECONDS_PER_SECOND + ts.tv_nsec) - + cxl_dstate->timestamp.last_set; + + /* Then adjust the actual time */ + stq_le_p(cmd->payload, cxl_dstate->timestamp.host_set + delta); + +done: + *len = 8; + return CXL_MBOX_SUCCESS; +} + +/* + * 8.2.9.3.2 + */ +define_mailbox_handler(TIMESTAMP_SET) +{ + struct timespec ts; + + clock_gettime(CLOCK_REALTIME, &ts); + + cxl_dstate->timestamp.set = true; + cxl_dstate->timestamp.last_set = + ts.tv_sec * NANOSECONDS_PER_SECOND + ts.tv_nsec; + + cxl_dstate->timestamp.host_set = le64_to_cpu(*(uint64_t *)cmd->payload); + + *len = 0; + return CXL_MBOX_SUCCESS; +} + QemuUUID cel_uuid; void cxl_process_mailbox(CXLDeviceState *cxl_dstate) diff --git a/include/hw/cxl/cxl_device.h b/include/hw/cxl/cxl_device.h index f88f844cb6..3dde7fb1fb 100644 --- a/include/hw/cxl/cxl_device.h +++ b/include/hw/cxl/cxl_device.h @@ -114,6 +114,12 @@ typedef struct cxl_device_state { size_t cel_size; }; + struct { + bool set; + uint64_t last_set; + uint64_t host_set; + } timestamp; + /* memory region for persistent memory, HDM */ uint64_t pmem_size; } CXLDeviceState;