spapr: Consolidate DRC state variables

Each DRC has three fields describing its state: isolation_state,
allocation_state and configured.  At first this seems like a reasonable
representation, since its based directly on the PAPR defined
isolation-state and allocation-state indicators.  However:
  * Only a few combinations of the two fields' values are permitted
  * allocation_state isn't used at all for physical DRCs
  * The indicators are write only so they don't really have a well
    defined current value independent of each other

This replaces these variables with a single state variable, whose names
and numbers are based on the diagram in LoPAPR section 13.4.  Along with
this we add code to check the current state on various operations and make
sure the requested transition is permitted.

Strictly speaking, this makes guest visible changes to behaviour (since we
probably allowed some transitions we shouldn't have before).  However, a
hypothetical guest broken by that wasn't PAPR compliant, and probably
wouldn't have worked under PowerVM.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>
Tested-by: Daniel Barboza <danielhb@linux.vnet.ibm.com>

1 files changed, 21 insertions, 4 deletions

diff --git a/include/hw/ppc/spapr_drc.h b/include/hw/ppc/spapr_drc.h
index 5fa502e465..4ceaaf0eff 100644
--- a/include/hw/ppc/spapr_drc.h
+++ b/include/hw/ppc/spapr_drc.h
@@ -173,6 +173,24 @@ typedef enum {
     SPAPR_DR_CC_RESPONSE_NOT_CONFIGURABLE = -9003,
 } sPAPRDRCCResponse;
 
+typedef enum {
+    /*
+     * Values come from Fig. 12 in LoPAPR section 13.4
+     *
+     * These are exposed in the migration stream, so don't change
+     * them.
+     */
+    SPAPR_DRC_STATE_INVALID             = 0,
+    SPAPR_DRC_STATE_LOGICAL_UNUSABLE    = 1,
+    SPAPR_DRC_STATE_LOGICAL_AVAILABLE   = 2,
+    SPAPR_DRC_STATE_LOGICAL_UNISOLATE   = 3,
+    SPAPR_DRC_STATE_LOGICAL_CONFIGURED  = 4,
+    SPAPR_DRC_STATE_PHYSICAL_AVAILABLE  = 5,
+    SPAPR_DRC_STATE_PHYSICAL_POWERON    = 6,
+    SPAPR_DRC_STATE_PHYSICAL_UNISOLATE  = 7,
+    SPAPR_DRC_STATE_PHYSICAL_CONFIGURED = 8,
+} sPAPRDRCState;
+
 /* rtas-configure-connector state */
 typedef struct sPAPRConfigureConnectorState {
     int fdt_offset;
@@ -189,14 +207,11 @@ typedef struct sPAPRDRConnector {
     /* DR-indicator */
     uint32_t dr_indicator;
 
-    /* sensor/indicator states */
-    uint32_t isolation_state;
-    uint32_t allocation_state;
+    uint32_t state;
 
     /* configure-connector state */
     void *fdt;
     int fdt_start_offset;
-    bool configured;
     sPAPRConfigureConnectorState *ccs;
 
     /* device pointer, via link property */
@@ -207,6 +222,8 @@ typedef struct sPAPRDRConnector {
 typedef struct sPAPRDRConnectorClass {
     /*< private >*/
     DeviceClass parent;
+    sPAPRDRCState empty_state;
+    sPAPRDRCState ready_state;
 
     /*< public >*/
     sPAPRDRConnectorTypeShift typeshift;