Merge branch 'for-7.4/cxl-dcd' into cxl-for-next

Part 1 of DCD support. Functionality disabled.

Documentation/cxl: Document DPA partition layout and ordering rules
cxl/core: Enforce partition order/simplify partition calls
cxl/mem: Configure dynamic capacity interrupts
cxl/pci: Factor out interrupt policy check
cxl/events: Split event msgnum configuration from irq setup
cxl/cdat: Gather DSMAS data for DCD partitions
cxl/mem: Read dynamic capacity configuration from the device
cxl/mbox: Flag support for Dynamic Capacity Devices (DCD)

1 files changed, 28 insertions, 1 deletions

diff --git a/include/cxl/cxl.h b/include/cxl/cxl.h
index 802b143de83d..1c04a7823f64 100644
--- a/include/cxl/cxl.h
+++ b/include/cxl/cxl.h
@@ -130,9 +130,30 @@ struct cxl_dpa_perf {
 	int qos_class;
 };
 
+/*
+ * Partitions share one flat DPA space in a fixed order:
+ *
+ *   DPA 0                                                     end
+ *   +---------------+---------------+---------------------------+
+ *   |      ram      |     pmem      |       dynamic_ram_1       |
+ *   +---------------+---------------+---------------------------+
+ *     part[0]         part[1]         part[2]
+ *
+ * The static ram and pmem partition order is mandated by CXL r4.0
+ * 8.2.10.9.2.1 "Get Partition Info" (opcode 4100h), Table 8-310: volatile
+ * capacity starts at DPA 0 and persistent capacity starts at the DPA
+ * immediately following it.  A dynamic partition has no such
+ * requirement -- 8.2.10.9.9.1 "Get Dynamic Capacity Configuration"
+ * (opcode 4800h), Table 8-347, only requires the DC Region Base to be
+ * 256MB aligned -- but Linux follows that precedent and requires it to
+ * start at the DPA immediately following static capacity: after pmem,
+ * after ram on a device with no pmem, or at DPA 0 on a device with no
+ * static capacity at all.  cxl_configure_dcd() enforces it.
+ */
 enum cxl_partition_mode {
 	CXL_PARTMODE_RAM,
 	CXL_PARTMODE_PMEM,
+	CXL_PARTMODE_DYNAMIC_RAM,
 };
 
 /**
@@ -140,14 +161,20 @@ enum cxl_partition_mode {
  * @res: shortcut to the partition in the DPA resource tree (cxlds->dpa_res)
  * @perf: performance attributes of the partition from CDAT
  * @mode: operation mode for the DPA capacity, e.g. ram, pmem, dynamic...
+ * @handle: DSMAS handle that represents this partition
+ * @shareable: Is the partition shareable (from its CDAT DSMAS entry)
+ * @read_only: Is the partition read-only (from its CDAT DSMAS entry)
  */
 struct cxl_dpa_partition {
 	struct resource res;
 	struct cxl_dpa_perf perf;
 	enum cxl_partition_mode mode;
+	u8 handle;
+	bool shareable;
+	bool read_only;
 };
 
-#define CXL_NR_PARTITIONS_MAX 2
+#define CXL_NR_PARTITIONS_MAX 3
 
 /**
  * struct cxl_dev_state - The driver device state