Cosmos/source2/Compiler/Cosmos.Compiler.DebugStub/Serial.cs
kudzu_cp 14c359c092
2012-07-08 05:49:50 +00:00

478 lines
15 KiB
C#

using System;
using System.Linq;
using Cosmos.Assembler;
using Cosmos.Assembler.x86;
namespace Cosmos.Debug.DebugStub {
public class Serial : Cosmos.Assembler.Code {
public Serial(Assembler.Assembler aAssembler) : base(aAssembler) {}
public override void Assemble() {
new Comment("X#: Group DebugStub");
new Comment("mComPortAddresses = 0x3F8, 0x2F8, 0x3E8, 0x2E8;");
new Comment("Currently hardcoded to COM1.");
new Comment("X#: var .ComAddr = $03F8");
mAssembler.DataMembers.Add(new DataMember("DebugStub_ComAddr", 0x03F8));
new Comment("All information relating to our serial usage should be documented in this comment.");
new Comment("http://wiki.osdev.org/Serial_ports");
new Comment("");
new Comment("We do not use IRQs for debugstub serial. This is becuase DebugStub (DS)");
new Comment("MUST be:");
new Comment("- As simple as possible");
new Comment("- Interact as minimal as possible wtih normal Cosmos code because");
new Comment("the debugstub must *always* work even if the normal code is fubarred");
new Comment("");
new Comment("The serial port that is used for DS should be 'hidden' from Cosmos main");
new Comment("so that Cosmos main pretends it does not exist.");
new Comment("");
new Comment("IRQs would create a clash/mix of code.");
new Comment("This does make the serial code in DebugStub inefficient, but its well worth");
new Comment("the benefits received by following these rules.");
new Comment("");
new Comment("Baud rate is set to 115200. Likely our code could not exceed this rate");
new Comment("anyways the way it is written and there are compatibility issues on some");
new Comment("hardware above this rate.");
new Comment("");
new Comment("We assume a minimum level of a 16550A, which should be no problem on any");
new Comment("common hardware today. VMWare emulates the 16550A");
new Comment("");
new Comment("We do not handle flow control for outbound data (DS --> DC).");
new Comment("The DebugConnector (DC, the code in the Visual Studio side) however is threaded");
new Comment("and easily should be able to receive data faster than we can send it.");
new Comment("Most things are transactional with data being sent only when asked for, but");
new Comment("with tracing we do send a data directly.");
new Comment("");
new Comment("Currently there is no inbound flow control either (DC --> DS)");
new Comment("For now we assume all commands in bound are 16 bytes or less to ensure");
new Comment("that they fit in the FIFO. Commands in DS must wait for a command ID ACK");
new Comment("before sending another command.");
new Comment("See notes in ProcessCommand.");
new Comment("");
new Comment("http:#www.nondot.org/sabre/os/files/Communication/ser_port.txt");
new Comment("Todo Auto params");
new Comment("Todo ebp frame ptr auto etc");
new Comment("X#: procedure InitSerial {");
new Label("DebugStub_InitSerial");
new Comment("X#: DX = .ComAddr");
new Mov { DestinationReg = RegistersEnum.DX , SourceRef = Cosmos.Assembler.ElementReference.New("DebugStub_ComAddr"), SourceIsIndirect = true };
new Comment("Disable interrupts");
new Comment("X#: BX = DX");
new Mov{ DestinationReg = RegistersEnum.BX, SourceReg = RegistersEnum.DX };
new Comment("X#: DX + 1");
new INC { DestinationReg = RegistersEnum.DX };
new Comment("X#: AL = 0");
new Mov{ DestinationReg = RegistersEnum.AL, SourceValue = 0 };
new Comment("X#: Port[DX] = AL");
new Out { DestinationReg = RegistersEnum.AL};
new Comment("Enable DLAB (set baud rate divisor)");
new Comment("X#: DX = BX");
new Mov{ DestinationReg = RegistersEnum.DX, SourceReg = RegistersEnum.BX };
new Comment("X#: DX + 3");
new Add { DestinationReg = RegistersEnum.DX, SourceValue = 3 };
new Comment("X#: AL = $80");
new Mov{ DestinationReg = RegistersEnum.AL, SourceValue = 0x80 };
new Comment("X#: Port[DX] = AL");
new Out { DestinationReg = RegistersEnum.AL};
new Comment("0x01, 0x00 - 115200");
new Comment("0x02, 0x00 - 57600");
new Comment("0x03, 0x00 - 38400");
new Comment("");
new Comment("Set divisor (lo byte)");
new Comment("X#: DX = BX");
new Mov{ DestinationReg = RegistersEnum.DX, SourceReg = RegistersEnum.BX };
new Comment("X#: AL = $01");
new Mov{ DestinationReg = RegistersEnum.AL, SourceValue = 0x01 };
new Comment("X#: Port[DX] = AL");
new Out { DestinationReg = RegistersEnum.AL};
new Comment("hi byte");
new Comment("X#: DX = BX");
new Mov{ DestinationReg = RegistersEnum.DX, SourceReg = RegistersEnum.BX };
new Comment("X#: DX + 1");
new INC { DestinationReg = RegistersEnum.DX };
new Comment("X#: AL = $00");
new Mov{ DestinationReg = RegistersEnum.AL, SourceValue = 0x00 };
new Comment("X#: Port[DX] = AL");
new Out { DestinationReg = RegistersEnum.AL};
new Comment("8N1");
new Comment("X#: DX = BX");
new Mov{ DestinationReg = RegistersEnum.DX, SourceReg = RegistersEnum.BX };
new Comment("X#: DX + 3");
new Add { DestinationReg = RegistersEnum.DX, SourceValue = 3 };
new Comment("X#: AL = $03");
new Mov{ DestinationReg = RegistersEnum.AL, SourceValue = 0x03 };
new Comment("X#: Port[DX] = AL");
new Out { DestinationReg = RegistersEnum.AL};
new Comment("Enable FIFO, clear them");
new Comment("Set 14-byte threshold for IRQ.");
new Comment("We dont use IRQ, but you cant set it to 0");
new Comment("either. IRQ is enabled/diabled separately");
new Comment("X#: DX = BX");
new Mov{ DestinationReg = RegistersEnum.DX, SourceReg = RegistersEnum.BX };
new Comment("X#: DX + 2");
new Add { DestinationReg = RegistersEnum.DX, SourceValue = 2 };
new Comment("X#: AL = $C7");
new Mov{ DestinationReg = RegistersEnum.AL, SourceValue = 0xC7 };
new Comment("X#: Port[DX] = AL");
new Out { DestinationReg = RegistersEnum.AL};
new Comment("0x20 AFE Automatic Flow control Enable - 16550 (VMWare uses 16550A) is most common and does not support it");
new Comment("0x02 RTS");
new Comment("0x01 DTR");
new Comment("Send 0x03 if no AFE");
new Comment("X#: DX = BX");
new Mov{ DestinationReg = RegistersEnum.DX, SourceReg = RegistersEnum.BX };
new Comment("X#: DX + 4");
new Add { DestinationReg = RegistersEnum.DX, SourceValue = 4 };
new Comment("X#: AL = $03");
new Mov{ DestinationReg = RegistersEnum.AL, SourceValue = 0x03 };
new Comment("X#: Port[DX] = AL");
new Out { DestinationReg = RegistersEnum.AL};
new Comment("X#: }");
new Label("DebugStub_InitSerial_Exit");
new Return();
new Comment("Modifies: AL, DX");
new Comment("X#: procedure ComReadAL {");
new Label("DebugStub_ComReadAL");
new Comment("X#: DX = .ComAddr");
new Mov { DestinationReg = RegistersEnum.DX , SourceRef = Cosmos.Assembler.ElementReference.New("DebugStub_ComAddr"), SourceIsIndirect = true };
new Comment("X#: DX + 5");
new Add { DestinationReg = RegistersEnum.DX, SourceValue = 5 };
new Comment("Wait for port to be ready");
new Comment("X#: Wait:");
new Label("DebugStub_ComReadAL_Wait");
new Comment("X#: AL = Port[DX]");
new IN { DestinationReg = RegistersEnum.AL};
new Comment("X#: AL ?& $01");
new Test { DestinationReg = RegistersEnum.AL, SourceValue = 0x01 };
new Comment("X#: if 0 goto Wait");
new ConditionalJump { Condition = ConditionalTestEnum.Zero, DestinationLabel = "DebugStub_ComReadAL_Wait" };
new Comment("X#: DX = .ComAddr");
new Mov { DestinationReg = RegistersEnum.DX , SourceRef = Cosmos.Assembler.ElementReference.New("DebugStub_ComAddr"), SourceIsIndirect = true };
new Comment("Read byte");
new Comment("X#: AL = Port[DX]");
new IN { DestinationReg = RegistersEnum.AL};
new Comment("X#: }");
new Label("DebugStub_ComReadAL_Exit");
new Return();
new Comment("Input: EDI");
new Comment("Output: [EDI]");
new Comment("Modified: AL, DX, EDI (+1)");
new Comment("");
new Comment("Reads a byte into [EDI] and does EDI + 1");
new Comment("X#: procedure ComRead8 {");
new Label("DebugStub_ComRead8");
new Comment("X#: Call .ComReadAL");
new Call { DestinationLabel = "DebugStub_ComReadAL" };
new Comment("X#: EDI[0] = AL");
new Mov{ DestinationReg = RegistersEnum.EDI, DestinationIsIndirect = true, DestinationDisplacement = 0, SourceReg = RegistersEnum.AL };
new Comment("X#: EDI + 1");
new INC { DestinationReg = RegistersEnum.EDI };
new Comment("X#: }");
new Label("DebugStub_ComRead8_Exit");
new Return();
new Comment("X#: procedure ComRead16 {");
new Label("DebugStub_ComRead16");
new Comment("X#: Call .ComRead8");
new Call { DestinationLabel = "DebugStub_ComRead8" };
new Comment("X#: Call .ComRead8");
new Call { DestinationLabel = "DebugStub_ComRead8" };
new Comment("X#: }");
new Label("DebugStub_ComRead16_Exit");
new Return();
new Comment("X#: procedure ComRead32 {");
new Label("DebugStub_ComRead32");
new Comment("X#: Call .ComRead8");
new Call { DestinationLabel = "DebugStub_ComRead8" };
new Comment("X#: Call .ComRead8");
new Call { DestinationLabel = "DebugStub_ComRead8" };
new Comment("X#: Call .ComRead8");
new Call { DestinationLabel = "DebugStub_ComRead8" };
new Comment("X#: Call .ComRead8");
new Call { DestinationLabel = "DebugStub_ComRead8" };
new Comment("X#: }");
new Label("DebugStub_ComRead32_Exit");
new Return();
new Comment("Input: AL");
new Comment("Output: None");
new Comment("Modifies: EDX, ESI");
new Comment("X#: procedure ComWriteAL {");
new Label("DebugStub_ComWriteAL");
new Comment("X#: +EAX");
new Push { DestinationReg = RegistersEnum.EAX};
new Comment("X#: ESI = ESP");
new Mov{ DestinationReg = RegistersEnum.ESI, SourceReg = RegistersEnum.ESP };
new Comment("X#: Call .ComWrite8");
new Call { DestinationLabel = "DebugStub_ComWrite8" };
new Comment("Is a local var, cant use Return(4). X# issues the return.");
new Comment("This also allows the function to preserve EAX.");
new Comment("X#: -EAX");
new Pop { DestinationReg = RegistersEnum.EAX};
new Comment("X#: }");
new Label("DebugStub_ComWriteAL_Exit");
new Return();
new Comment("X#: procedure ComWrite8 {");
new Label("DebugStub_ComWrite8");
new Comment("Input: ESI");
new Comment("Output: None");
new Comment("Modifies: EAX, EDX");
new Comment("");
new Comment("Sends byte at [ESI] to com port and does esi + 1");
new Comment("");
new Comment("This sucks to use the stack, but x86 can only read and write ports from AL and");
new Comment("we need to read a port before we can write out the value to another port.");
new Comment("The overhead is a lot, but compared to the speed of the serial and the fact");
new Comment("that we wait on the serial port anyways, its a wash.");
new Comment("");
new Comment("This could be changed to use interrupts, but that then complicates");
new Comment("the code and causes interaction with other code. DebugStub should be");
new Comment("as isolated as possible from any other code.");
new Comment("Sucks again to use DX just for this, but x86 only supports");
new Comment("8 bit address for literals on ports");
new Comment("X#: DX = .ComAddr");
new Mov { DestinationReg = RegistersEnum.DX , SourceRef = Cosmos.Assembler.ElementReference.New("DebugStub_ComAddr"), SourceIsIndirect = true };
new Comment("X#: DX + 5");
new Add { DestinationReg = RegistersEnum.DX, SourceValue = 5 };
new Comment("Wait for serial port to be ready");
new Comment("Bit 5 (0x20) test for Transmit Holding Register to be empty.");
new Comment("X#: Wait:");
new Label("DebugStub_ComWrite8_Wait");
new Comment("X#: AL = Port[DX]");
new IN { DestinationReg = RegistersEnum.AL};
new Comment("X#: AL ?& $20");
new Test { DestinationReg = RegistersEnum.AL, SourceValue = 0x20 };
new Comment("X#: if 0 goto Wait");
new ConditionalJump { Condition = ConditionalTestEnum.Zero, DestinationLabel = "DebugStub_ComWrite8_Wait" };
new Comment("Set address of port");
new Comment("X#: DX = $03F8");
new Mov{ DestinationReg = RegistersEnum.DX, SourceValue = 0x03F8 };
new Comment("Get byte to send");
new Comment("X#: AL = ESI[0]");
new Mov{ DestinationReg = RegistersEnum.AL, SourceReg = RegistersEnum.ESI, SourceIsIndirect = true, SourceDisplacement = 0 };
new Comment("Send the byte");
new Comment("X#: Port[DX] = AL");
new Out { DestinationReg = RegistersEnum.AL};
new Comment("X#: ESI++");
new INC { DestinationReg = RegistersEnum.ESI };
new Comment("X#: }");
new Label("DebugStub_ComWrite8_Exit");
new Return();
new Comment("X#: procedure ComWrite16 {");
new Label("DebugStub_ComWrite16");
new Comment("X#: Call .ComWrite8");
new Call { DestinationLabel = "DebugStub_ComWrite8" };
new Comment("X#: Call .ComWrite8");
new Call { DestinationLabel = "DebugStub_ComWrite8" };
new Comment("X#: }");
new Label("DebugStub_ComWrite16_Exit");
new Return();
new Comment("X#: procedure ComWrite32 {");
new Label("DebugStub_ComWrite32");
new Comment("X#: Call .ComWrite8");
new Call { DestinationLabel = "DebugStub_ComWrite8" };
new Comment("X#: Call .ComWrite8");
new Call { DestinationLabel = "DebugStub_ComWrite8" };
new Comment("X#: Call .ComWrite8");
new Call { DestinationLabel = "DebugStub_ComWrite8" };
new Comment("X#: Call .ComWrite8");
new Call { DestinationLabel = "DebugStub_ComWrite8" };
new Comment("X#: }");
new Label("DebugStub_ComWrite32_Exit");
new Return();
new Comment("X#: procedure ComWriteX {");
new Label("DebugStub_ComWriteX");
new Comment("X#: More:");
new Label("DebugStub_ComWriteX_More");
new Comment("X#: Call .ComWrite8");
new Call { DestinationLabel = "DebugStub_ComWrite8" };
new Comment("X#: ECX--");
new Dec { DestinationReg = RegistersEnum.ECX };
new Comment("X#: if !0 goto More");
new ConditionalJump { Condition = ConditionalTestEnum.NotZero, DestinationLabel = "DebugStub_ComWriteX_More" };
new Comment("X#: }");
new Label("DebugStub_ComWriteX_Exit");
new Return();
}
}
}