[PATCH v2 4/6] OvmfPkg/QemuFwCfgLib: extend lib class header with more definitions

[Laszlo Ersek <lersek@redhat.com>]

The last patch consists purely of code movement; going forward, we should
use a few more symbolic constants.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
---

Notes:
    v2:
    - split these out to a separate patch

 OvmfPkg/Include/Library/QemuFwCfgLib.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/OvmfPkg/Include/Library/QemuFwCfgLib.h b/OvmfPkg/Include/Library/QemuFwCfgLib.h
index 40a07456c530..3e017d53a97e 100644
--- a/OvmfPkg/Include/Library/QemuFwCfgLib.h
+++ b/OvmfPkg/Include/Library/QemuFwCfgLib.h
@@ -24,12 +24,20 @@
 #define QEMU_FW_CFG_FNAME_SIZE 56
 
 //
+// If the following bit is set in the UINT32 fw_cfg revision / feature bitmap
+// -- read from key 0x0001 with the basic IO Port or MMIO method --, then the
+// DMA interface is available.
+//
+#define FW_CFG_F_DMA BIT1
+
+//
 // Macros for the FW_CFG_DMA_ACCESS.Control bitmap (in native encoding).
 //
 #define FW_CFG_DMA_CTL_ERROR  BIT0
 #define FW_CFG_DMA_CTL_READ   BIT1
 #define FW_CFG_DMA_CTL_SKIP   BIT2
 #define FW_CFG_DMA_CTL_SELECT BIT3
+#define FW_CFG_DMA_CTL_WRITE  BIT4
 
 typedef enum {
   QemuFwCfgItemSignature            = 0x0000,
-- 
2.9.2