From c422bb60193512663c4854ee1ac6c1217f5e3178 Mon Sep 17 00:00:00 2001
From: Daniel Kiper <daniel.kiper@oracle.com>
Date: Mon, 5 Mar 2018 15:11:18 +0100
Subject: [PATCH] ieee1275: no-data-command bus specific method

IEEE 1275-1994 Standard for Boot (Initialization Configuration)
Firmware: Core Requirements and Practices

E.3.2.2 Bus-specific methods for bus nodes

A package implementing the scsi-2 device type shall implement the
following bus-specific method:

no-data-command ( cmd-addr -- error? )
Executes a simple SCSI command, automatically retrying under
certain conditions.  cmd-addr is the address of a 6-byte command buffer
containing an SCSI command that does not have a data transfer phase.
Executes the command, retrying indefinitely with the same retry criteria
as retry-command.

error? is nonzero if an error occurred, zero otherwise.
NOTE no-data-command is a convenience function. It provides
no capabilities that are not present in retry-command, but for
those commands that meet its restrictions, it is easier to use.

Signed-off-by: Eric Snowberg <eric.snowberg@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
 grub-core/kern/ieee1275/ieee1275.c | 51 ++++++++++++++++++++++++++++++++++++++
 include/grub/ieee1275/ieee1275.h   |  3 +++
 2 files changed, 54 insertions(+)

diff --git a/grub-core/kern/ieee1275/ieee1275.c b/grub-core/kern/ieee1275/ieee1275.c
index 497f170fb6b..cd2dead832d 100644
--- a/grub-core/kern/ieee1275/ieee1275.c
+++ b/grub-core/kern/ieee1275/ieee1275.c
@@ -733,3 +733,54 @@ grub_ieee1275_set_address (grub_ieee1275_ihandle_t ihandle,
 
   return args.catch_result;
 }
+
+int
+grub_ieee1275_no_data_command (grub_ieee1275_ihandle_t ihandle,
+                               const void *cmd_addr, grub_ssize_t *result)
+{
+  struct set_address
+  {
+    struct grub_ieee1275_common_hdr common;
+    grub_ieee1275_cell_t method;
+    grub_ieee1275_cell_t ihandle;
+    grub_ieee1275_cell_t cmd_addr;
+    grub_ieee1275_cell_t error;
+    grub_ieee1275_cell_t catch_result;
+  }
+  args;
+
+  INIT_IEEE1275_COMMON (&args.common, "call-method", 3, 2);
+
+  /*
+   * IEEE 1275-1994 Standard for Boot (Initialization Configuration)
+   * Firmware: Core Requirements and Practices
+   *
+   * E.3.2.2 Bus-specific methods for bus nodes
+   *
+   * A package implementing the scsi-2 device type shall implement the
+   * following bus-specific method:
+   *
+   * no-data-command ( cmd-addr -- error? )
+   * Executes a simple SCSI command, automatically retrying under
+   * certain conditions.  cmd-addr is the address of a 6-byte command buffer
+   * containing an SCSI command that does not have a data transfer phase.
+   * Executes the command, retrying indefinitely with the same retry criteria
+   * as retry-command.
+   *
+   * error? is nonzero if an error occurred, zero otherwise.
+   * NOTE no-data-command is a convenience function. It provides
+   * no capabilities that are not present in retry-command, but for
+   * those commands that meet its restrictions, it is easier to use.
+   */
+  args.method = (grub_ieee1275_cell_t) "no-data-command";
+  args.ihandle = ihandle;
+  args.cmd_addr = (grub_ieee1275_cell_t) cmd_addr;
+
+  if (IEEE1275_CALL_ENTRY_FN (&args) == -1)
+    return -1;
+
+  if (result)
+    *result = args.error;
+
+  return args.catch_result;
+}
diff --git a/include/grub/ieee1275/ieee1275.h b/include/grub/ieee1275/ieee1275.h
index 55e920e816f..6dfb57b8bf8 100644
--- a/include/grub/ieee1275/ieee1275.h
+++ b/include/grub/ieee1275/ieee1275.h
@@ -213,6 +213,9 @@ int EXPORT_FUNC(grub_ieee1275_milliseconds) (grub_uint32_t *msecs);
 int EXPORT_FUNC(grub_ieee1275_set_address) (grub_ieee1275_ihandle_t ihandle,
                                             grub_uint32_t target,
                                             grub_uint32_t lun);
+int EXPORT_FUNC(grub_ieee1275_no_data_command) (grub_ieee1275_ihandle_t ihandle,
+                                                const void *cmd_addr,
+                                                grub_ssize_t *result);
 int EXPORT_FUNC(grub_ieee1275_decode_unit4) (grub_ieee1275_ihandle_t ihandle,
                                              void *addr, grub_size_t size,
                                              grub_uint32_t *phy_lo,