From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34157) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bzwBI-0004sE-Dq for qemu-devel@nongnu.org; Thu, 27 Oct 2016 21:42:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bzwBH-0004zJ-4y for qemu-devel@nongnu.org; Thu, 27 Oct 2016 21:42:04 -0400 From: David Gibson Date: Fri, 28 Oct 2016 12:38:08 +1100 Message-Id: <1477618694-21019-68-git-send-email-david@gibson.dropbear.id.au> In-Reply-To: <1477618694-21019-1-git-send-email-david@gibson.dropbear.id.au> References: <1477618694-21019-1-git-send-email-david@gibson.dropbear.id.au> Subject: [Qemu-devel] [PULL 67/73] spapr: update spapr hotplug documentation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: peter.maydell@linaro.org Cc: agraf@suse.de, clg@kaod.org, thuth@redhat.com, lvivier@redhat.com, aik@ozlabs.ru, mark.cave-ayland@ilande.co.uk, mdroth@linux.vnet.ibm.com, bharata@linux.vnet.ibm.com, qemu-ppc@nongnu.org, qemu-devel@nongnu.org, David Gibson From: Michael Roth This updates the existing documentation to reflect recent updates to the hotplug event structure, which are in draft form but slated for inclusion in PAPR/LoPAPR. Signed-off-by: Michael Roth Reviewed-by: David Gibson Signed-off-by: David Gibson --- docs/specs/ppc-spapr-hotplug.txt | 55 +++++++++++++++++++++++++++++++++------- 1 file changed, 46 insertions(+), 9 deletions(-) diff --git a/docs/specs/ppc-spapr-hotplug.txt b/docs/specs/ppc-spapr-hotplug.txt index 631b0ca..f57e2a0 100644 --- a/docs/specs/ppc-spapr-hotplug.txt +++ b/docs/specs/ppc-spapr-hotplug.txt @@ -233,12 +233,27 @@ tools by host-level management such as an HMC. This level of management is not applicable to PowerKVM, hence the reason for extending the notification framework to support hotplug events. -Note that these events are not yet formally part of the PAPR+ specification, -but support for this format has already been implemented in DR-related -guest tools such as powerpc-utils/librtas, as well as kernel patches that have -been submitted to handle in-kernel processing of memory/cpu-related hotplug -events[1], and is planned for formal inclusion is PAPR+ specification. The -hotplug-specific payload is QEMU implemented as follows (with all values +The format for these EPOW-signalled events is described below under +"hotplug/unplug event structure". Note that these events are not +formally part of the PAPR+ specification, and have been superseded by a +newer format, also described below under "hotplug/unplug event structure", +and so are now deemed a "legacy" format. The formats are similar, but the +"modern" format contains additional fields/flags, which are denoted for the +purposes of this documentation with "#ifdef GUEST_SUPPORTS_MODERN" guards. + +QEMU should assume support only for "legacy" fields/flags unless the guest +advertises support for the "modern" format via ibm,client-architecture-support +hcall by setting byte 5, bit 6 of it's ibm,architecture-vec-5 option vector +structure (as described by LoPAPR v11, B.6.2.3). As with "legacy" format events, +"modern" format events are surfaced to the guest via check-exception RTAS calls, +but use a dedicated event source to signal the guest. This event source is +advertised to the guest by the addition of a "hot-plug-events" node under +"/event-sources" node of the guest's device tree using the standard format +described in LoPAPR v11, B.6.12.1. + +== hotplug/unplug event structure == + +The hotplug-specific payload in QEMU is implemented as follows (with all values encoded in big-endian format): struct rtas_event_log_v6_hp { @@ -263,14 +278,23 @@ struct rtas_event_log_v6_hp { #define RTAS_LOG_V6_HP_ACTION_ADD 1 #define RTAS_LOG_V6_HP_ACTION_REMOVE 2 uint8_t hotplug_action; /* action (add/remove) */ -#define RTAS_LOG_V6_HP_ID_DRC_NAME 1 -#define RTAS_LOG_V6_HP_ID_DRC_INDEX 2 -#define RTAS_LOG_V6_HP_ID_DRC_COUNT 3 +#define RTAS_LOG_V6_HP_ID_DRC_NAME 1 +#define RTAS_LOG_V6_HP_ID_DRC_INDEX 2 +#define RTAS_LOG_V6_HP_ID_DRC_COUNT 3 +#ifdef GUEST_SUPPORTS_MODERN +#define RTAS_LOG_V6_HP_ID_DRC_COUNT_INDEXED 4 +#endif uint8_t hotplug_identifier; /* type of the resource identifier, * which serves as the discriminator * for the 'drc' union field below */ +#ifdef GUEST_SUPPORTS_MODERN + uint8_t capabilities; /* capability flags, currently unused + * by QEMU + */ +#else uint8_t reserved; +#endif union { uint32_t index; /* DRC index of resource to take action * on @@ -278,6 +302,19 @@ struct rtas_event_log_v6_hp { uint32_t count; /* number of DR resources to take * action on (guest chooses which) */ +#ifdef GUEST_SUPPORTS_MODERN + struct { + uint32_t count; /* number of DR resources to take + * action on + */ + uint32_t index; /* DRC index of first resource to take + * action on. guest will take action + * on DRC index through + * DRC index in + * sequential order + */ + } count_indexed; +#endif char name[1]; /* string representing the name of the * DRC to take action on */ -- 2.7.4