OvmfPkg/LsiScsiDxe: Process the SCSI Request Packet

This is the second part of LsiScsiPassThru(). LsiScsiProcessRequest() is
added to translate the SCSI Request Packet into the LSI 53C895A
commands. This function utilizes the so-called Script buffer to transmit
a series of commands to the chip and then polls the DMA Status (DSTAT)
register until the Scripts Interrupt Instruction Received (SIR) bit
sets. Once the script is done, the SCSI Request Packet will be modified
to reflect the result of the script. The Cumulative SCSI Byte Count
(CSBC) register is fetched before and after the script to calculate the
transferred bytes and update InTransferLength/OutTransferLength if
necessary.

v3:
  - Set DStat, SIst0, and SIst1 to 0 before using them
  - Amend the if statements for the DMA data instruction and add the
    assertions for the data direction
  - Also set SenseDataLength to 0 on the error path
  - Fix typos and amend comments
  - Amend the error handling of the calculation of transferred bytes
v2:
  - Use the BITx macros for the most of LSI_* constants
  - Fix a typo: contorller => controller
  - Add SeaBIOS lsi-scsi driver as one of the references of the script
  - Cast the result of sizeof to UINT32 for the instructions of the
    script
  - Drop the backslashes
  - Replace LSI_SCSI_DMA_ADDR_LOW with LSI_SCSI_DMA_ADDR since we
    already removed DUAL_ADDRESS_CYCLE
  - Add more comments for the script
  - Fix the check of the script size at the end of the script
  - Always set SenseDataLength to 0 to avoid the caller to access
    SenseData
  - Improve the error handling in LsiScsiProcessRequest()

Cc: Jordan Justen <[email protected]>
Cc: Laszlo Ersek <[email protected]>
Cc: Ard Biesheuvel <[email protected]>
Signed-off-by: Gary Lin <[email protected]>
Message-Id: <[email protected]>
Reviewed-by: Laszlo Ersek <[email protected]>

OvmfPkg/Include/IndustryStandard/LsiScsi.h

@@ -25,6 +25,19 @@
 #define LSI_REG_DSP               0x2C
 #define LSI_REG_SIST0             0x42
 #define LSI_REG_SIST1             0x43
+#define LSI_REG_CSBC              0xDC
+
+//
+// The status bits for DMA Status (DSTAT)
+//
+#define LSI_DSTAT_IID             BIT0
+#define LSI_DSTAT_R               BIT1
+#define LSI_DSTAT_SIR             BIT2
+#define LSI_DSTAT_SSI             BIT3
+#define LSI_DSTAT_ABRT            BIT4
+#define LSI_DSTAT_BF              BIT5
+#define LSI_DSTAT_MDPE            BIT6
+#define LSI_DSTAT_DFE             BIT7
 
 //
 // The status bits for Interrupt Status Zero (ISTAT0)
@@ -38,4 +51,55 @@
 #define LSI_ISTAT0_SRST           BIT6
 #define LSI_ISTAT0_ABRT           BIT7
 
+//
+// The status bits for SCSI Interrupt Status Zero (SIST0)
+//
+#define LSI_SIST0_PAR             BIT0
+#define LSI_SIST0_RST             BIT1
+#define LSI_SIST0_UDC             BIT2
+#define LSI_SIST0_SGE             BIT3
+#define LSI_SIST0_RSL             BIT4
+#define LSI_SIST0_SEL             BIT5
+#define LSI_SIST0_CMP             BIT6
+#define LSI_SIST0_MA              BIT7
+
+//
+// The status bits for SCSI Interrupt Status One (SIST1)
+//
+#define LSI_SIST1_HTH             BIT0
+#define LSI_SIST1_GEN             BIT1
+#define LSI_SIST1_STO             BIT2
+#define LSI_SIST1_R3              BIT3
+#define LSI_SIST1_SBMC            BIT4
+#define LSI_SIST1_R5              BIT5
+#define LSI_SIST1_R6              BIT6
+#define LSI_SIST1_R7              BIT7
+
+//
+// LSI 53C895A Script Instructions
+//
+#define LSI_INS_TYPE_BLK          0x00000000
+#define LSI_INS_TYPE_IO           BIT30
+#define LSI_INS_TYPE_TC           BIT31
+
+#define LSI_INS_BLK_SCSIP_DAT_OUT 0x00000000
+#define LSI_INS_BLK_SCSIP_DAT_IN  BIT24
+#define LSI_INS_BLK_SCSIP_CMD     BIT25
+#define LSI_INS_BLK_SCSIP_STAT    (BIT24 | BIT25)
+#define LSI_INS_BLK_SCSIP_MSG_OUT (BIT25 | BIT26)
+#define LSI_INS_BLK_SCSIP_MSG_IN  (BIT24 | BIT25 | BIT26)
+
+#define LSI_INS_IO_OPC_SEL        0x00000000
+#define LSI_INS_IO_OPC_WAIT_RESEL BIT28
+
+#define LSI_INS_TC_CP             BIT17
+#define LSI_INS_TC_JMP            BIT19
+#define LSI_INS_TC_RA             BIT23
+
+#define LSI_INS_TC_OPC_JMP        0x00000000
+#define LSI_INS_TC_OPC_INT        (BIT27 | BIT28)
+
+#define LSI_INS_TC_SCSIP_DAT_OUT  0x00000000
+#define LSI_INS_TC_SCSIP_MSG_IN   (BIT24 | BIT25 | BIT26)
+
 #endif // _LSI_SCSI_H_