refactor: organize code into proper components

drivers/nvme/nvme.asm

@@ -5,8 +5,6 @@
 ;;                                                              ;;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
-;driver sceletone
-
 format PE DLL native
 entry START
 
@@ -27,21 +25,29 @@ include "../peimport.inc"
 include "nvme.inc"
 
 proc START c, reason:dword
+
         cmp     [reason], DRV_ENTRY
-        jne     .exit
+        jne     .err
+
 .entry:
-        push    esi
 		DEBUGF  DBG_INFO, "Detecting NVMe hardware...\n"
-        call    detect
+        call    detect_nvme
-        pop     esi
         test    eax, eax
-        jz      .exit
+        jz      .err ; no NVMe device found?
+		DEBUGF  DBG_INFO, "Found NVMe device...\n"
+
+		stdcall nvme_init, dword [eax + PCIDEV.bus], dword [eax + PCIDEV.devfn]
+		test    eax, eax
+		jz      .err ; failed to initialize controller?
 
         invoke  RegService, my_service, service_proc
         ret
-.exit:
+
+.err:
+		call    nvme_cleanup
         xor     eax, eax
         ret
+
 endp
 
 proc service_proc stdcall, ioctl:dword
@@ -53,111 +59,106 @@ proc service_proc stdcall, ioctl:dword
 
         mov     eax, [ebx+IOCTL.output]
         cmp     [ebx+IOCTL.out_size], 4
-        jne     .fail
+        jne     @F
         mov     dword [eax], API_VERSION
         xor     eax, eax
         ret
 @@:
-.fail:
         or      eax, -1
         ret
+
 endp
 
 proc memset stdcall, p_data:dword, val:byte, sz:dword
+
 		mov     bh, byte [val]
-	xor eax, eax
+		xor     ecx, ecx 
 @@:
-	mov byte [p_data + eax], bh
+		mov     byte [p_data + ecx], bh
-	inc eax
+		inc     ecx
-	test eax, dword [sz]
+		cmp     ecx, dword [sz]
-	jnz @b
+		jne     @b
+		xor     eax, eax
 		ret
+
 endp
 
 ; Submit a Command in the Admin Submission Queue
 proc submit_asq stdcall, p_sq:dword
+
 		xor 	eax, eax
 		ret
+
 endp
 
 proc nvme_identify stdcall, nsid:dword, dptr:dword, cns:byte
+
 		sub     esp, sizeof.SQ_ENTRY
 		stdcall memset, esp, 0, sizeof.SQ_ENTRY
+
 		mov     eax, dword [nsid]
-	mov [esp + SQ_ENTRY.nsid], eax
+		mov     dword [esp + SQ_ENTRY.nsid], eax
 		mov     eax, dword [dptr]
 		mov     dword [esp + SQ_ENTRY.dptr], eax
-	; TODO: setting CID to 0 for now but later on keep a list of unique list of identifiers
+		mov     dword [esp + SQ_ENTRY.cdw0], ADM_CMD_IDENTIFY ; TODO: setting CID to 0 for now but later on keep a unique list of identifiers
-	mov dword [esp + SQ_ENTRY.cdw0], ADM_CMD_IDENTIFY
 		mov     ah, byte [cns]
 		mov     byte [esp + SQ_ENTRY.cdw10], ah
 		stdcall submit_asq, esp
+
 		add     esp, sizeof.SQ_ENTRY
 		xor     eax, eax
 		ret
+
 endp
 
-proc detect
+; 
-        push    ebx
+proc detect_nvme
+
         invoke  GetPCIList
 		mov 	edx, eax
+
 .check_dev:
-		mov 	ecx, [eax+PCIDEV.class]
+		mov 	ebx, dword [eax + PCIDEV.class]
-		and		ecx, 0x00ffff00 ; retrieve class/subclass code only
+		and		ebx, 0x00ffff00 ; retrieve class/subclass code only
-		cmp 	ecx, 0x00010800 ; Mass Storage Controller - Non-Volatile Memory Controller
+		cmp 	ebx, 0x00010800 ; Mass Storage Controller - Non-Volatile Memory Controller
-		je		.check_cap
+		je		.found_dev
+
 .next_dev:
-		mov		eax, [eax + PCIDEV.fd]
+		mov		eax, dword [eax + PCIDEV.fd]
 		cmp		eax, edx
 		jne 	.check_dev
+		xor     eax, eax ; no more PCI devices to enumerate?
 
-		; no more PCI devices to enumerate?
+.found_dev:
-		xor     eax, eax
-		pop     ebx
 		ret
-.check_cap:
-		push eax
-		movzx ebx, [eax + PCIDEV.bus]
-		mov [pcidev_bus], ebx
-		movzx ebx, [eax + PCIDEV.devfn]
-		mov [pcidev_devfn], ebx
-		invoke PciRead16, [pcidev_bus], [pcidev_devfn], PCI_header00.status
-		test ax, 0x10 ; check capabilities list bit
-		jnz .got_cap
-		pop eax
-.got_cap:
-		DEBUGF DBG_INFO,"Found NVMe device with capabilities\n"
-		invoke PciRead8, [pcidev_bus], [pcidev_devfn], PCI_header00.cap_ptr
-		and eax, 11111100b
-		mov edi, eax
-@@:
-		invoke PciRead32, [pcidev_bus], [pcidev_devfn], edi
-		mov ecx, eax
-		;and ecx, 0xff
-		mov eax, ecx
-		movzx edi, ah
-		test edi, edi
-		jnz @b
 
-		; read BAR0
+endp
-		invoke PciRead32, [pcidev_bus], [pcidev_devfn], PCI_header00.base_addr_0
+
+; nvme_init: Initializes the NVMe controller 
+proc nvme_init, bus:dword, devfn:dword
+
+		invoke   PciRead32, [bus], [devfn], PCI_header00.base_addr_0
 		and      eax, 0xfffffff0
 		test     eax, eax
-		jz .no_mmio
+		jz       .exit_fail
+
 		invoke   MapIoMem, eax, sizeof.NVME_REG_MAP, PG_SW+PG_NOCACHE
 		test     eax, eax
-		jz .no_mmio
+		jz       .exit_fail
 		mov      [p_mmap], eax
 		mov      ebx, dword [eax + NVME_REG_MAP.CAP]
 		DEBUGF   DBG_INFO, "(NVMe) Maximum queue entries supported: %u\n", bx
 		test     ebx, CAP_CQR
 		jz       .cqr_not_req
 		DEBUGF   DBG_INFO, "(NVMe) Contiguous queues required\n"
+
 .cqr_not_req:
 		mov      ebx, dword [eax + NVME_REG_MAP.CAP + 4]
 		mov      ecx, ebx
 		test     ebx, CAP_CSS_NVM_CMDSET
 		jz       .exit_fail
+
+		if __DEBUG__
 			and      ebx, CAP_MPSMIN
 			and      ecx, CAP_MPSMAX
 			shr      ebx, 16
@@ -171,58 +172,42 @@ proc detect
 			and      ecx, CC_IOCQES
 			shl      ebx, 16
 			shl      ecx, 16
-		DEBUGF DBG_INFO,"(NVMe) I/O Submission Queue Entry Size: %u\n", ebx
+
+			; TODO: Change entry sizes to their appropriate values
+			DEBUGF   DBG_INFO,"(NVMe) I/O Submission Queue entry Size: %u\n", ebx
 			DEBUGF   DBG_INFO,"(NVMe) I/O completion queue entry size: %u\n", ecx
-		; Initialize the controller
+		end if
 
-		invoke KernelAlloc, sizeof.NVME_IDENT_CONTROLLER
-		test eax, eax
-		jz .alloc_ident_controller_fail
-		mov [p_ident], eax
-		stdcall nvme_identify, 0, dword [p_ident], CNS_IDCS
-		mov ecx, dword [p_ident]
-		mov edx, dword [ecx + NVME_IDENT_CONTROLLER.tnvmcap]
-		DEBUGF DBG_INFO,"Total NVMe SSD capacity: %ub\n", edx
-
-		; return successfully
-		call nvme_cleanup
-		pop 	eax
-        pop     ebx
         xor     eax, eax
         inc     eax
         ret
 
-.alloc_ident_controller_fail:
-		DEBUGF DBG_INFO,"ERROR: failed to allocate %u bytes for 'NVME_IDENT_CONTROLLER'\n", sizeof.NVME_IDENT_CONTROLLER
-		jmp .exit_fail
-.no_mmio:
-		DEBUGF DBG_INFO,"ERROR: NVMe Device has no MMIO\n"
 .exit_fail:
-		pop eax
+		DEBUGF  DBG_INFO, "ERROR: failed to initialize NVMe controller\n"
-		pop ebx
 		xor eax, eax
 		ret
+
 endp
 
 proc nvme_cleanup
+
 		mov eax, [p_ident]
 		test eax, eax
 		jz @f
-	invoke Kfree, eax
+		invoke KernelFree, eax
 @@:
 		ret
+
 endp
 
 ; uninitialized data
 align 4
-pcidev_bus			dd ?
-pcidev_devfn		dd ?
 		p_mmap              dd ?
 		p_ident             dd ?
 
 ;all initialized data place here
 align 4
-my_service   db "NVMe Service",0  ;max 16 chars include zero
+		my_service   db "NVME",0  ;max 16 chars include zero
 		include_debug_strings
 
 align 4