The Datafile PD-CD 4

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Text File | 1995-06-16 | 16.3 KB | 848 lines

GET Asm:h.Standard MB * 1024*1024 KB * 1024 ; This is the start & size of kernel in memory KERNEL_START * 24*MB KERNEL_SIZE * 512*KB ; This is the address used to map unused pages to NULL_MAPPING * 31*MB ; This is the start & size of screen memory SCREEN_START * 32512*KB SCREEN_SIZE * 256*KB SWI OS_GetEnv MOV r13,r1 ; set up stack SUB r1,r13,#32*1024 STR r1,memmapinfo ; Place to store mem map info BL process_options ADRL r0,oos LDRB r0,[r0,#1] TEQ r0,#0 BNE skip_00 SWI OS_WriteS = 22,31,31,10,10,"Linux (c) Linus Torvalds, ported to the Archimedes by " = "R.M.King (2 June 1994)",13,10,13,10,0 skip_00 BL check_memmap ; Check the map BL load_kernel ; Load kernel into memory STMFD sp!,{r0} ADR r0,shutdown SWI OS_CLI ADRL r0,oos LDR r0,[r0] TST r0,#&FF TSTNE r0,#&FF0000 BLEQ continue BL move_code ; Move 'move' code to page ; BL show_movelist ; Show memory move list LDMFD sp!,{r2} ; MOV r0,r2 ; BL show_moveinfo ; SWI OS_Exit SWI OS_EnterOS ; *** POINT OF NO RETURN ****** TEQP pc,#&0C000003 ; Disable interrupts LDR r0,=&03200000 ; Get MEMC address MOV r1,#0 STRB r1,[r0,#&18] STRB r1,[r0,#&28] STRB r1,[r0,#&38] LDR r0,movelist LDR r1,endofmovelist LDR r3,pagesize LDR r4,numpages LDR r8,kernel_start LDR r9,kernel_size MOV pc,r2 ; Call move code SWI OS_Exit continue STMFD sp!,{r0-r2,lr} SWI OS_NewLine SWI OS_WriteS = "You will lose all data in RISC OS. Continue? (Y/N)",0 SWI OS_Confirm SWINE OS_Exit = "Loading... Please wait...",0 LDMFD sp!,{r0-r2,pc}^ shutdown = "Shutdown",0 check_memmap STMFD sp!,{lr} SWI OS_ReadMemMapInfo ; Get page size etc & show info STR r0,pagesize STR r1,numpages TEQ r0,#&8000 TEQNE r0,#&4000 BNE badpagesize ADRL r4,oos LDRB r4,[r4,#1] TEQ r4,#0 MOV r4,r1 BNE skip_01 SUB r1,sp,#16 MOV r2,#14 SWI OS_ConvertCardinal3 SWI OS_WriteS = 13,10," RAM page size is ",0 SWI OS_Write0 SWI OS_WriteS = " bytes, with ",0 MOV r0,r4 SUB r1,sp,#16 MOV r2,#14 SWI OS_ConvertCardinal3 SWI OS_Write0 SWI OS_WriteS = " pages.",13,10,0 skip_01 LDR r0,memmapinfo MOV r1,#0 MOV r2,#0 getmemlp STR r1,[r0,r2] ADD r2,r2,#3*4 ADD r1,r1,#1 TEQ r1,r4 BNE getmemlp MVN r1,#0 STR r1,[r0,r2] SWI OS_ReadMemMapEntries ; Read current mapping ; SWI OS_WriteS ; = 13,10," Sorting pages...",0 MOV r2,#4 MOV r1,#0 MOV r5,#&10000 killbadpglp LDR r3,[r0,r2] ; Remove those outsize our range CMP r3,r5 MOVCC r3,#0 STRCC r3,[r0,r2] CMP r3,r0 MOVCS r3,#0 STRCS r3,[r0,r2] ADD r2,r2,#3*4 ADD r1,r1,#1 TEQ r1,r4 BNE killbadpglp ; SWI OS_WriteS ; = 13,10," Pages available: ",0 ; MOV r2,#4 ; MOV r1,#0 ;listpglp LDR r3,[r0,r2] ; TEQ r3,#0 ; BLNE page_avail ; ADD r2,r2,#3*4 ; ADD r1,r1,#1 ; TEQ r1,r4 ; BNE listpglp LDMFD sp!,{pc} endcode DCD end_code-endcode pagesize DCD 0 numpages DCD 0 memmapinfo DCD 0 add_move STMFD sp!,{r0-r1,r4-r7,lr} MOV r0,r9 MUL r0,r6,r0 ADD r0,r0,r4 ADD r0,r0,#&02000000 LDR r1,endofmovelist STR r2,[r1],#4 STR r0,[r1],#4 STR r1,endofmovelist LDMFD sp!,{r0-r1,r4-r7,pc}^ ;show_movelist STMFD sp!,{lr} ; LDR r3,movelist ; LDR r4,endofmovelist ;show_movelistlp CMP r3,r4 ; LDMCSFD sp!,{pc}^ ; LDR r0,[r3],#4 ; LDR r1,[r3],#4 ; BL show_moveinfo ; B show_movelistlp movelist DCD 0 endofmovelist DCD 0 kernel_handle DCD 0 kernel_start DCD KERNEL_START kernel_size DCD KERNEL_SIZE kernel_fn = "<Linux$Dir>.Kernel",0 load_kernel STMFD sp!,{lr} STMFD sp!,{r0,r2-r5} MOV r0,#17 ADR r1,kernel_fn SWI OS_File STR r2,kernel_start ADD r4,r4,#&800 BIC r4,r4,#&7F00 BIC r4,r4,#&00FF ADD r4,r4,#&8000 STR r4,kernel_size LDMFD sp!,{r0,r2-r5} MOV r0,#&4F SWI OS_Find BVS load_error STR r0,kernel_handle MOV r1,r0 LDR r8,memmapinfo ADD r8,r8,#4 MOV r7,#0 ; Page number counter LDR r6,pagesize MOV r4,#(32+256)*1024 MOV r9,#0 pageslp SUBS r4,r4,r6 ; Find start of kernel ADDPL r9,r9,#1 BPL pageslp LDR r4,kernel_size ADD r4,r4,r6 ; Page for parameters MOV r5,r9 pages2lp SUBS r4,r4,r6 ; Find start of free ram ADDPL r5,r5,#1 BPL pages2lp MOV r4,#0 BL find_freepage STR r2,movelist STR r2,endofmovelist MOV r0,#1 STR r0,[r8,r3,LSL#2] ; Make page unavailable load_kernellp ADD r3,r7,r9 ; Start of kernel MOV r11,r3 ADD r3,r3,r3,LSL#1 ; Get offset LDR r2,[r8,r3,LSL#2] CMP r2,#2 ; If page unavailable, BLCC find_freepage ; Get a free page BLCC add_move MOV r0,#1 STR r0,[r8,r3,LSL#2] ; Make page unavailable MOV r0,#4 MOV r3,r6 ; BL load_info ; SWICC &100+'r' ; SWICS &100+'c' SWI XOS_GBPB ; Read page BVS load_error ADD r7,r7,#1 ; Next page TEQ r3,#0 BEQ load_kernellp ; If not end, repeat SUB r3,r6,#1 ADD r4,r4,#&800 BIC r4,r4,r3 ADD r4,r4,r6 ; Move into next page SUB r7,r5,#1 ; Page number for parameters MOV r0,#0 STR r0,kernel_handle SWI OS_Find ; Close file MOV r3,r7 MOV r11,r3 ADD r3,r3,r3,LSL#1 ; Get offset LDR r2,[r8,r3,LSL#2] CMP r2,#2 BLCC find_freepage ; Find a free page BLCC add_move MOV r0,#1 STR r0,[r8,r3,LSL#2] ; Prevent this page being grabbed ; BL load_info ; SWICC &100+'R' ; SWICS &100+'C' BL get_kernel_info ADD r7,r7,#1 ; Increment page counter BL find_freepage ; Get a free page for move routines MOV r0,r11 MUL r0,r6,r0 ADD r0,r0,#&02000000 LDMFD sp!,{pc} find_freepage STMFD sp!,{r0-r1,r4-r7,lr} find_freelp ADD r3,r5,r5,LSL#1 LDR r2,[r8,r3,LSL#2] CMP r2,#2 MOVCS r11,r5 LDMCSFD sp!,{r0-r1,r4-r7,pc}^ ADDCC r5,r5,#1 TEQ r5,#128 BNE find_freelp ADR r0,nomemerror load_error MOV r7,r0 LDR r1,kernel_handle TEQ r1,#0 MOVNE r0,#0 SWINE OS_Find MOV r0,r7 SWI OS_GenerateError nomemerror = 0,0,0,0,"*** Out of memory ***",0 ;load_info STMFD sp!,{r0-r8,lr} ; MOV r3,r2 ; SWI OS_WriteS ; = 13,10," Loading kernel code &",0 ; MOV r0,r4 ; SUB r1,sp,#16 ; MOV r2,#14 ; SWI OS_ConvertHex8 ; SWI OS_Write0 ; SWI OS_WriteS ; = " at &",0 ; MOV r0,r3 ; SUB r1,sp,#16 ; MOV r2,#14 ; SWI OS_ConvertHex8 ; SWI OS_Write0 ; SWI &100+'(' ; MOV r0,#9 ;; MOV r0,r11 ; MUL r0,r6,r0 ; ADD r0,r0,#&02000000 ; ADD r0,r0,r4 ; SUB r1,sp,#16 ; MOV r2,#14 ; SWI OS_ConvertHex8 ; SWI OS_Write0 ; SWI &100+')' ; LDMFD sp!,{r0-r8,pc}^ ;page_avail STMFD sp!,{r0-r2,lr} ; MOV r0,r1 ; SUB r1,sp,#16 ; MOV r2,#14 ; SWI OS_ConvertCardinal1 ; SWI OS_Write0 ; SWI &100+',' ; SWI &100+' ' ; LDMFD sp!,{r0-r2,pc}^ printdec STMFD sp!,{r0-r2,lr} SUB r1,sp,#16 MOV r2,#14 SWI OS_ConvertCardinal4 SWI OS_Write0 LDMFD sp!,{r0-r2,pc}^ badpagesize SWI OS_WriteS = 13,10,10,"*** Cannot start linux - can only handle 16KB or 32KB page sizes." = 13,10,0 SWI OS_Exit ;show_moveinfo STMFD sp!,{r0-r4,lr} ; MOV r7,r1 ; SWI OS_WriteS ; = 13,10," Relocate ",0 ; SUB r1,sp,#16 ; MOV r2,#14 ; SWI OS_ConvertHex8 ; SWI OS_Write0 ; SWI &100+'-' ; SWI &100+'>' ; MOV r0,r7 ; SUB r1,sp,#16 ; MOV r2,#14 ; SWI OS_ConvertHex8 ; SWI OS_Write0 ; LDMFD sp!,{r0-r4,pc}^ ;showstack STMFD sp!,{r0-r2,lr} ; MOV r0,r2 ; SUB r1,sp,#16 ; MOV r2,#14 ; SWI OS_ConvertHex8 ; SWI OS_Write0 ; LDMFD sp!,{r0-r2,pc}^ ; Set up & display current kernel information configfile = "<Linux$Dir>.Config",0 set_kernel_info STMFD sp!,{r2,r7,lr} MOV r7,r2 LDR r0,pagesize STR r0,[r7] ; Page size (bytes) LDR r0,numpages STR r0,[r7,#4] ; Number of pages MOV r0,#0 ; Disable Sound DMA MOV r1,#1<<11 SWI XOS_UpdateMEMC STR r0,[r7,#9*4] MOV r0,#161 ; Read SoundDefault parameters MOV r1,#148 SWI XOS_Byte STRB r2,[r7,#10*4] MOV r0,#161 ; Read ADFS Drives info MOV r1,#135 SWI XOS_Byte STRB r2,[r7,#10*4+1] MOV r0,#165 ; Read current o/p cursor position SWI XOS_Byte TEQ r1,#0 ADDNE r2,r2,#4 ADDEQ r2,r2,#3 MOVNE r1,#0 STR r1,[r7,#7*4] STR r2,[r7,#8*4] MOV r1,#100 MOV r2,#75 STR r1,[r7,#5*4] STR r2,[r7,#6*4] MOV r1,#4 MOV r2,#8 STRB r1,[r7,#10*4+2] STRB r2,[r7,#10*4+3] LDMFD sp!,{r2,r7,pc}^ get_kernel_info STMFD sp!,{r0-r12,lr} ; BL showstack BL set_kernel_info MOV r0,#0 STR r0,[r2,#8] ; Ram disk size STR r0,[r2,#12] ; Mount root read-only STR r0,[r2,#&100] ; Command line STR r0,[r2,#&200] ; Command line STR r0,[r2,#&300] ; Command line STR r0,[r2,#&400] ; Command line STR r0,[r2,#&500] ; Command line MOV r0,#&200 ; Root dev STR r0,[r2,#16] MOV r7,r2 ADR r1,configfile MOV r0,#&4C SWI XOS_Find BVS showkernelinfo TEQ r0,#0 BEQ showkernelinfo MOV r1,r0 MOV r0,#4 MOV r2,r7 MOV r3,#&1000 SWI XOS_GBPB MOV r0,#0 SWI XOS_Find MOV r2,r7 BL set_kernel_info ADRL r2,oos LDRB r2,[r2] TEQ r2,#0 LDMNEFD sp!,{r0-r12,pc}^ showkernelinfo ADRL r2,oos MOV r1,#0 STRB r1,[r2,#2] ; Clear 'sure' flag MOV r2,r7 SWI &100+28 SWI &100+0 SWI OS_WriteS = 43,79,15,12,26 = 31,1,16,11, "Current configuration:",10 = 10,13, " Page size : ",0 LDR r0,[r2] BL printdec SWI OS_WriteS = " bytes",31,40,17," Num pages : ",0 LDR r0,[r2,#4] BL printdec SWI OS_WriteS = 10,10,13, "<R>am Disc Size : ",0 LDR r0,[r2,#8] BL printdec SWI OS_WriteS = "K",31,40,19, "<M>ount root rdonly: ",0 LDR r0,[r2,#12] TEQ r0,#0 SWIEQ &100+'N' SWINE &100+'Y' SWI OS_WriteS = 13,10,10, "<C>ommand line : ",0 ADD r0,r2,#&500 SWI OS_Write0 MOV r3,#1 MOV r4,#1 MOV r5,#4 ADD r6,r2,#&100 BL show_hdfile ADD r6,r6,#&80 BL show_hdfile ADD r6,r6,#&80 BL show_hdfile ADD r6,r6,#&80 BL show_hdfile MOV r4,#1 MOV r5,#5 ADD r6,r6,#&80 BL show_hdfile ADD r6,r6,#&80 BL show_hdfile ADD r6,r6,#&80 BL show_hdfile ADD r6,r6,#&80 BL show_hdfile SWI OS_WriteS = 13,10,10,"<S>ave & Run",31,40,39,"<Q>uit" = 13,10,10,"Select first letter to change (RMCS):",0 MOV r0,#126 SWI OS_Byte SWI OS_ReadC MOV r2,r7 TEQ r0,#'M' TEQNE r0,#'m' BEQ change_rootrdonly TEQ r0,#'R' TEQNE r0,#'r' BEQ change_ramdiscsize TEQ r0,#'C' TEQNE r0,#'c' BEQ change_comdline TEQ r0,#'Q' TEQNE r0,#'q' SWIEQ OS_Exit SUB r1,r0,#1 AND r4,r1,#3 ADD r4,r4,#1 MOV r5,r1,LSR#2 BIC r5,r5,#&FC ORR r5,r5,#4 ADD r6,r7,#&80 AND r1,r0,#15 ADD r6,r6,r1,LSL#7 TEQ r0,#'1' TEQNE r0,#'2' TEQNE r0,#'3' TEQNE r0,#'4' TEQNE r0,#'5' TEQNE r0,#'6' TEQNE r0,#'7' TEQNE r0,#'8' BEQ newfile TEQ r0,#'S' TEQNE r0,#'s' BNE showkernelinfo SWI OS_NewLine MOV r0,#&8C ADR r1,configfile SWI XOS_Find BVS err TEQ r0,#0 BEQ err MOV r1,r0 MOV r0,#2 MOV r2,r7 MOV r3,#&1000 SWI XOS_GBPB MOV r0,#0 SWI XOS_Find err MOV r2,r7 BL set_kernel_info LDMFD sp!,{r0-r12,pc} show_hdfile STMFD sp!,{lr} SWI &100+13 SWI &100+10 SWI &100+10 SWI &100+'<' ADD r0,r3,#&30 SWI XOS_WriteC SWI XOS_WriteS = "> Partition ",0 ALIGN ADD r0,r4,#&30 SWI XOS_WriteC SWI XOS_WriteS = " : ADFS::",0 ALIGN ADD r0,r5,#&30 SWI XOS_WriteC SWI XOS_WriteS = ".$.",0 ALIGN MOV r0,r6 SWI XOS_Write0 ADD r3,r3,#1 ADD r4,r4,#1 LDMFD sp!,{pc}^ change_rootrdonly LDR r0,[r2,#12] EOR r0,r0,#1 STR r0,[r2,#12] B showkernelinfo change_ramdiscsize SWI OS_WriteS = "R",10,10,13,"New ram disc size (0 = none) : ",0 ADD r0,r2,#&200 MOV r1,#&100 MOV r2,#32 MOV r3,#&7E SWI OS_ReadLine BCS showkernelinfo MOV r0,#10 ADD r1,r7,#&200 SWI XOS_ReadUnsigned BVS showkernelinfo LDR r1,[r7] SUB r1,r1,#1 ADD r2,r2,r1,LSR#10 BIC r2,r2,r1,LSR#10 STR r2,[r7,#8] B showkernelinfo change_comdline SWI OS_WriteS = "C",10,10,13,"New command line (ret:none/esc:cancel): ",0 ADD r0,r7,#&500 comdin STMFD sp!,{r0} ADD r0,r2,#&1000 MOV r1,#&100 MOV r2,#32 MOV r3,#&7E SWI OS_ReadLine LDMFD sp!,{r0} BCS showkernelinfo ADD r2,r7,#&1000 MOV r3,#0 cpycmdlinelp STRB r3,[r0,r1] SUBS r1,r1,#1 LDRPLB r3,[r2,r1] BPL cpycmdlinelp B showkernelinfo getfile1 SWI OS_WriteS = "1",10,10,13,"New partition file 1 (ret:none/esc:cancel): ",0 ADD r0,r7,#&100 B comdin getfile2 SWI OS_WriteS = "2",10,10,13,"New partition file 2 (ret:none/esc:cancel): ",0 ADD r0,r7,#&200 B comdin getfile3 SWI OS_WriteS = "3",10,10,13,"New partition file 3 (ret:none/esc:cancel): ",0 ADD r0,r7,#&300 B comdin getfile4 SWI OS_WriteS = "4",10,10,13,"New partition file 4 (ret:none/esc:cancel): ",0 ADD r0,r7,#&400 B comdin newfile SWI XOS_WriteC SWI XOS_WriteS = 10,10,13,"New partition file ",0 ALIGN ADD r0,r4,#&30 SWI XOS_WriteC SWI XOS_WriteS = " (ret:none/esc:cancel): ADFS::",0 ALIGN ADD r0,r5,#&30 SWI XOS_WriteC SWI XOS_WriteS = ".$.",0 ALIGN MOV r0,r6 B comdin process_options STMFD sp!,{lr} 00 LDRB r2,[r0],#1 TEQ r2,#0 LDMEQFD sp!,{pc}^ TEQ r2,#' ' TEQNE r2,#9 BNE %b00 ; Search for space char 01 LDRB r2,[r0],#1 TEQ r2,#' ' TEQNE r2,#9 BEQ %b01 ; Search for non-space char TEQ r2,#0 LDMEQFD sp!,{pc}^ TEQ r2,#'-' BNE %b00 ; Check for '-' ADR r3,opts MOV r5,#0 MOV r1,r0 ; Save current pointer 02 LDRB r4,[r3],#1 TEQ r4,#0 BEQ %f04 LDRB r2,[r0],#1 EOR r2,r4,r2 BICS r2,r2,#&20 BEQ %b02 MOV r0,r1 03 LDRB r4,[r3],#1 TEQ r4,#0 BNE %b03 ADD r5,r5,#1 LDRB r4,[r3] TEQ r4,#0 BNE %b02 B %b00 04 LDRB r2,[r0],#1 TEQ r2,#' ' TEQNE r2,#9 TEQNE r2,#0 BNE %b00 ADR r2,oos MOV r3,#1 STRB r3,[r2,r5] SUB r0,r0,#1 B %b00 LDMFD sp!,{pc}^ oos = 0,0,0,0 DCD 0 opts = "run",0,"quiet",0,"sure",0,0 ; Code to move the area from pagemovecode to pageendmovecode to correct pages in physical ; memory. move_code ADR r3,pagemovecode ADR r4,pageendmovecode MOV r1,r2 move_codelp LDR r0,[r3],#4 STR r0,[r1],#4 CMP r3,r4 BCC move_codelp MOV pc,lr ; NO EXTRA FUNCTIONS AFTER HERE! This section gets copied to a free page so that we ; can shift the kernel to the correct location with no fear of overwriting the copying ; routines. ; Routines to copy pages to correct locations ; This better be correct! ; This code is run at a place where it is not going to be overwritten ; and so has to be *fully* relocateable ; Entry conditions: ; r0 Start of page move list ; r1 End of page move list ; r2 * Unused * ; r3 Page size ; r4 Number of pages ; r5 * Unused * ; r6 * Unused * ; r7 * Unused * ; r8 Start of kernel ; r9 Length of kernel ; r10 * Unused * ; r11 * Unused * ; r12 * Unused * ; r13 * Unused * ; r14 * Unused * pagemovecode pagemove1lp CMP r0,r1 BCS endmove LDR r2,[r0],#4 ; Page address to copy from LDR r7,[r0],#4 ; Page address to copy to MOV r5,r3 ; Page size pagemove2lp SUBS r5,r5,#4 LDRPL r6,[r2],#4 ; Get word from 'from' page STRPL r6,[r7],#4 ; Put word to 'to' page BPL pagemove2lp B pagemove1lp ; Routines to map pages into correct locations in memory ; The kernel has to copy this mapping exactly when it has booted endmove STR r8,kernel_start1 STR r9,kernel_size1 MOV r0,#0 ; Phew! Time to remap MOV r1,#SCREEN_START ; Start of screen mem remap1lp BL remap_page ; Remap screen memory ADD r0,r0,#1 ADD r1,r1,r3 CMP r1,#SCREEN_START+SCREEN_SIZE BCC remap1lp MOV r1,#0 remap2lp BL remap_page ; Map in a page in addrs 0-0x8000 ADD r0,r0,#1 ADD r1,r1,r3 CMP r1,#&8000 ; Top of page 0 BCC remap2lp LDR r1,kernel_start1 ; Remap kernel code pages LDR r6,kernel_size1 ADD r6,r1,r6 ; End of kernel code ADD r5,r6,r3 ; Page for parameters & stack remap3lp BL remap_page ADD r0,r0,#1 ADD r1,r1,r3 CMP r1,r5 BCC remap3lp remap4lp MOV r1,#NULL_MAPPING ; Remap all other pages to nothing BL remap_pagep ADD r0,r0,#1 ; ADD r1,r1,r3 CMP r0,r4 BCC remap4lp LDR r2,kernel_start1 ORR r2,r2,#&0C000003 ; Ensure user mode & irqs disabled MOV sp,r6 MOV r0,r6 LDR r1,kernel_size1 MOV pc,r2 ; Call kernel (And hope...) kernel_start1 DCD 0 kernel_size1 DCD 0 ; Must preserve r0,r1,r3,r4,r5,r6 ; r0 = physical page ; r1 = logical page remap_page MOV r2,#0 ; Page user read/write B remap_pagedo remap_pagep MOV r2,#&00000300 remap_pagedo MOV r8,#&007F0000 ORR r8,r8,#&0000F000 AND r8,r1,r8 AND r9,r1,#&01800000 ORR r8,r8,r9,LSR#(23-10) ORR r8,r8,r2 TEQ r3,#16*1024 BEQ page_16 AND r9,r0,#&0F MOV r9,r9,LSL#3 TST r0,#&10 ORRNE r9,r9,#1 TST r0,#&20 ORRNE r9,r9,#4 TST r0,#&40 ORRNE r9,r9,#2 page_do AND r7,r0,#&80 ORR r9,r9,r7 ORR r8,r8,r9 ORR r8,r8,#&03800000 STR r8,[r8] MOV pc,lr page_16 AND r9,r0,#&1F MOV r9,r9,LSL#2 AND r7,r0,#&60 ORR r9,r9,r7,LSR#5 B page_do pageendmovecode DCD 0 end_code DCD 0 END