Clarify 4KB alignment

Signed-off-by: Jiewen Yao <[email protected]>

specification/09-coveio_abi.adoc

@@ -155,7 +155,7 @@ The possible error codes returned in `sbiret.error` are shown below.
 struct sbiret sbi_covh_add_tvm_interface_region(unsigned long tvm_id,
                                                 unsigned long device_if_id,
                                                 unsigned long base_addr,
-                                                unsigned long num_pages);
+                                                unsigned long region_len);
 -----
 
 Adds a device interface MMIO region into a TVM address space.
@@ -170,6 +170,10 @@ enable the created mappings until the TVM accepts the TDI in its TCB.
 
 The possible error codes returned in `sbiret.error` are shown below.
 
+`base_addr` value must be 4KB-aligned.
+
+`region_len` value must be 4KB-aligned.
+
 [#table_sbi_covh_add_tvm_interface_region]
 .CoVE Host Add TVM Interface Region
 [cols="2,3", width=90%, align="center", options="header"]
@@ -185,7 +189,7 @@ The possible error codes returned in `sbiret.error` are shown below.
 struct sbiret sbi_covh_reclaim_tvm_interface_region(unsigned long tvm_id,
                                                     unsigned long device_if_id,
                                                     unsigned long base_addr,
-                                                    unsigned long num_pages);
+                                                    unsigned long region_len);
 -----
 
 Reclaims a device interface MMIO region previously added to a TVM address space.
@@ -320,7 +324,7 @@ first.
 
 `slot_id` must be between 0 and 7 inclusive.
 
-`cert_addr_out` must be page aligned.
+`cert_addr_out` must be 4KB-aligned.
 
 The possible error codes returned in `sbiret.error` are shown below.
 
@@ -365,7 +369,7 @@ valid and the rest bits are igored. The last `GET_MEASUREMENT` request must
 set `SignatureRequested` bit to request the digital signaure of the measurement
 transcript.
 
-Both `msmt_addr_out` and `nonce_addr` must be page aligned.
+Both `msmt_addr_out` and `nonce_addr` must be 4KB-aligned.
 
 The possible error codes returned in `sbiret.error` are shown below.
 
@@ -426,7 +430,7 @@ Gets the TDISP interface report for the device interface.
 The TSM returns the interface report, as defined by the <<TDISP>> TDI Report
 Structure, at the `if_report_out` address.
 
-`if_report_out` must be page aligned.
+`if_report_out` must be 4KB-aligned.
 
 The possible error codes returned in `sbiret.error` are shown below.
 
@@ -502,7 +506,7 @@ the trusted `TDISP`-reported MMIO regions. The TSM will enable those mappings
 if the TVM calls the starts the device interface through the
 `sbi_covg_start_interface` function.
 
-All of `gpa_addr`, `hpa_addr` and `size` values must be page aligned.
+All of `gpa_addr`, `hpa_addr` and `size` values must be 4KB-aligned.
 
 The possible error codes returned in `sbiret.error` are shown below.