Code optimization (by size)

git-svn-id: svn://kolibrios.org@4289 a494cfbc-eb01-0410-851d-a64ba20cac60
This commit is contained in:
Yogev Ezra 2013-11-25 01:15:59 +00:00
parent 7194db1dd6
commit 3951e5fd59

View File

@ -44,7 +44,7 @@ if ~ VORTEX86DEBUG
end if
mov dx, 0xcf8 ; CF8h = Vortex86 PCI Configuration Address port
mov eax, 0x80000090 ; 0x80000090 = Starting PCI address to read from (32-bit register - accessed as DWORD)
mov eax, OS_BASE+0x90 ; 0x80000090 = Starting PCI address to read from (32-bit register - accessed as DWORD)
out dx, eax ; Send request to PCI address port to retrieve data from this address
mov dx, 0xcfc ; CFCh = Vortex86 PCI Configuration Data port
in eax, dx ; Read data (SoC type) from PCI data port
@ -54,44 +54,44 @@ if VORTEX86DEBUG ; When in debug mode, pretend that we re
end if
DEBUGF 1, "K : Vortex86 SoC register returned 0x"
test eax, eax ; We need to break out in case the result is '\0' since otherwise we will fail at NULL string
jz .nullPCIoutput
mov [Vortex86CPUcode], eax
DEBUGF 1, "%x (%s): ", eax, Vortex86CPUcode
cmp ax, 4d44h ; Check whether it's Vortex86 family (all Vortex86 SoC have ID in form of "0xNN504d44")
jnz .notVortex86
shr eax, 16 ; Discard lower word in EAX which is always 4d44h in Vortex86 family
cmp al, 50h ; The 3rd byte is always 50h in Vortex86 SoC (if this is the case, we need just the highest byte)
jnz .notVortex86
mov bl, ah ; Copy SoC type to BL since EAX (that includes AH) is used implicitly in "LODSD" command below
test eax, eax ; Check whether the port output was '\0'
jz .nullPCIoutput ; In case the result is '\0' (NULL), skip further testing and exit
mov [Vortex86CPUcode], eax ; Save HEX CPU code to Vortex86CPUcode (so it can be used later)
DEBUGF 1, "%x (%s): ", eax, Vortex86CPUcode ; Print the CPU code (as HEX and as string) to debug log
mov ebx, 0x444d5000 ; Apply Vortex86 CPU code mask (all Vortex86 SoC have ID in form of "0xNN504d44")
bswap eax ; Assumed it is Vortex86 SoC, the highest byte identifies the exact CPU, so move it to the lowest byte
mov bl, al ; Copy SoC type to BL since EAX (that includes AL) is used implicitly in "LODSD" command below
cmp eax, ebx ; Now see whether the 3 higher bytes were "0x504d44" (which means it's Vortex86)
jnz .notVortex86 ; Sorry, it's not Vortex86 - go say so and exit
mov esi, Vortex86SoClist ; ESI points to the start of Vortex86SoClist (used implicitly in "LODSD" command below)
xor ecx, ecx ; Zero ECX (it is used as counter)
cld ; Clears the DF flag in the EFLAGS register (DF=0 --> String operations increment ESI)
@@:
inc ecx ; Increment our counter
cmp ecx, Vortex86SoCnum ; Check if we iterated Vortex86SoCnum times already (i.e. went over the entire Vortex86SoClist)
ja .unknownVortex86 ; If the entire list was tested and our CPU is not in that list, it is unknown Vortex86 SoC
inc ecx ; Increment our counter
lodsd ; Load DWORD at address DS:ESI into EAX (puts 1 line from Vortex86SoClist into EAX, then increments ESI)
cmp bl, al ; Check if our CPU matches the current record in the list
jne @b ; No match --> repeat with next record
shr eax, 8 ; Match found --> drop the SoC type code from Vortex86SoClist name and replace it with \0
mov dword [Vortex86SoCname+8], eax ; Concatenate it with prefix to receive complete SoC name (\0 is string termination)
mov [Vortex86CPUid], cl ; Save the CPUid (1=Vortex86SX, 2=Vortex86DX, ..., Vortex86SoCnum+1=Unknown Vortex86)
DEBUGF 1, "%s (id=%d)\n", Vortex86SoCname, [Vortex86CPUid]:1
jmp .Vortex86end ; Say what we have found (CPU name and id) and exit
.nullPCIoutput: ; Emulators and non-Vortex86 CPU computers will usually return \0 in this register
DEBUGF 1, "0 (NULL)\n"
DEBUGF 1, "%s (id=%d)\n", Vortex86SoCname, [Vortex86CPUid]:1 ; Say what we have found (CPU name and id)
jmp .Vortex86end
.notVortex86: ; In case this register is used by other CPUs for other purpose, it's interesting what it contains
DEBUGF 1, "not a Vortex86 CPU\n"
jmp .Vortex86end
.unknownVortex86:
mov [Vortex86CPUid], cl ; Save the CPUid (Vortex86SoCnum+1=Unknown Vortex86)
DEBUGF 1, "unknown Vortex86 CPU (id=%d, last known is %d)\n", [Vortex86CPUid]:1, Vortex86SoCnum
jmp .Vortex86end
.notVortex86: ; In case this register is used by other CPUs for other purpose, it's interesting what it contains
DEBUGF 1, "not a Vortex86 CPU\n"
.nullPCIoutput: ; Emulators and non-Vortex86 CPU computers will usually return \0 in this register
DEBUGF 1, "0 (NULL)\n"
.Vortex86end: