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-Let's investigate final protocol that was attached to our `ImageHandle` - `EFI_SHELL_PARAMETERS_PROTOCOL`
-
-https://github.com/tianocore/edk2/blob/master/MdePkg/Include/Protocol/ShellParameters.h
-```
-typedef struct _EFI_SHELL_PARAMETERS_PROTOCOL {
- ///
- /// Points to an Argc-element array of points to NULL-terminated strings containing
- /// the command-line parameters. The first entry in the array is always the full file
- /// path of the executable. Any quotation marks that were used to preserve
- /// whitespace have been removed.
- ///
- CHAR16 **Argv;
-
- ///
- /// The number of elements in the Argv array.
- ///
- UINTN Argc;
-
- ///
- /// The file handle for the standard input for this executable. This may be different
- /// from the ConInHandle in EFI_SYSTEM_TABLE.
- ///
- SHELL_FILE_HANDLE StdIn;
-
- ///
- /// The file handle for the standard output for this executable. This may be different
- /// from the ConOutHandle in EFI_SYSTEM_TABLE.
- ///
- SHELL_FILE_HANDLE StdOut;
-
- ///
- /// The file handle for the standard error output for this executable. This may be
- /// different from the StdErrHandle in EFI_SYSTEM_TABLE.
- ///
- SHELL_FILE_HANDLE StdErr;
-} EFI_SHELL_PARAMETERS_PROTOCOL;
-```
-
-As we see, we can access command line arguments that was passed to our program through this protocol.
-Let's use it in our `MemoryInfo` program.
-
-In the last lesson we've printed our EFI memory map. It had >100 entries.
-When you boot Linux kernel, you can see some info about the current memory map, but this table is much shorter. It happens because of two facts:
-- Kernel differentiate EFI memory types much less granular. Instead of `EfiReservedMemoryType`/`EfiLoaderCode`/`EfiLoaderData`/...` it simply has only 4 types: `usable`/`ACPI NVS`/`ACPI data`/`reserved`
-- Kernel glues adjacent regions together
-
-
-I've generated kernel image for EFI x86-64 with buildroot:
-```
-cd ~
-git clone https://github.com/buildroot/buildroot.git
-cd buildroot
-make pc_x86_64_efi_defconfig
-make
-```
-
-If we try to boot this kernel with:
-```
-qemu-system-x86_64 -drive if=pflash,format=raw,file=Build/OvmfX64/RELEASE_GCC5/FV/OVMF.fd
- -drive format=raw,file=fat:rw:~/UEFI_disk
- -nographic
- -kernel ~/buildroot/output/images/bzImage
- -append "console=ttyS0"
-```
-
-In kernel boot log we can see:
-```
-BIOS-provided physical RAM map:
-BIOS-e820: [mem 0x0000000000000000-0x000000000009ffff] usable
-BIOS-e820: [mem 0x0000000000100000-0x00000000007fffff] usable
-BIOS-e820: [mem 0x0000000000800000-0x0000000000807fff] ACPI NVS
-BIOS-e820: [mem 0x0000000000808000-0x000000000080ffff] usable
-BIOS-e820: [mem 0x0000000000810000-0x00000000008fffff] ACPI NVS
-BIOS-e820: [mem 0x0000000000900000-0x00000000078eefff] usable
-BIOS-e820: [mem 0x00000000078ef000-0x0000000007b6efff] reserved
-BIOS-e820: [mem 0x0000000007b6f000-0x0000000007b7efff] ACPI data
-BIOS-e820: [mem 0x0000000007b7f000-0x0000000007bfefff] ACPI NVS
-BIOS-e820: [mem 0x0000000007bff000-0x0000000007ef3fff] usable
-BIOS-e820: [mem 0x0000000007ef4000-0x0000000007f77fff] reserved
-BIOS-e820: [mem 0x0000000007f78000-0x0000000007ffffff] ACPI NVS
-BIOS-e820: [mem 0x00000000ffc00000-0x00000000ffffffff] reserved
-```
-
-Let's modify our `MemoryInfo` program:
-- if `full` option is passed, we print memory map as we do now
-- if no option is passed, we print memory map in a "Linux kernel way"
-
-First, add `full` boolean flag. If argument "full" is passed to our program, we'll set this flag, else it would be equal to `false`.
-```
-EFI_SHELL_PARAMETERS_PROTOCOL* ShellParameters;
-
-Status = gBS->HandleProtocol(
- ImageHandle,
- &gEfiShellParametersProtocolGuid,
- (VOID **) &ShellParameters
-);
-
-BOOLEAN full=FALSE;
-if (Status == EFI_SUCCESS) {
- if (ShellParameters->Argc == 2) {
- if (!StrCmp(ShellParameters->Argv[1], L"full")) {
- full=TRUE;
- }
- }
-}
-```
-
-To use `EFI_SHELL_PARAMETERS_PROTOCOL` we need to add include file:
-```
-#include <Protocol/ShellParameters.h>
-```
-And add GUID to the application *.inf file:
-```
-[Protocols]
- gEfiShellParametersProtocolGuid
-```
-
-Now to the next problem. Create a function for OS memory type mapping:
-```
-const CHAR16 *memory_types_OS_view[] = {
- L"reserved", // L"EfiReservedMemoryType",
- L"usable", // L"EfiLoaderCode",
- L"usable", // L"EfiLoaderData",
- L"usable", // L"EfiBootServicesCode",
- L"usable", // L"EfiBootServicesData",
- L"reserved", // L"EfiRuntimeServicesCode",
- L"reserved", // L"EfiRuntimeServicesData",
- L"usable", // L"EfiConventionalMemory",
- L"reserved", // L"EfiUnusableMemory",
- L"ACPI data",// L"EfiACPIReclaimMemory",
- L"ACPI NVS", // L"EfiACPIMemoryNVS",
- L"reserved", // L"EfiMemoryMappedIO",
- L"reserved", // L"EfiMemoryMappedIOPortSpace",
- L"reserved", // L"EfiPalCode",
- L"usable", // L"EfiPersistentMemory",
- L"usable", // L"EfiMaxMemoryType"
-};
-
-const CHAR16 *
-memory_type_to_str_OS_view(UINT32 type)
-{
- if (type > sizeof(memory_types_OS_view)/sizeof(CHAR16 *))
- return L"Unknown";
-
- return memory_types_OS_view[type];
-}
-```
-
-And finally we need to modify our program to glue adjacent regions with the same type together if the `full` flag is not set:
-```
-EFI_MEMORY_DESCRIPTOR* desc = MemoryMap;
-EFI_MEMORY_DESCRIPTOR* next_desc;
-int i = 0;
-while ((UINT8 *)desc < (UINT8 *)MemoryMap + MemoryMapSize) {
- UINTN PAGE_SIZE = 4096;
- UINTN mapping_size =(UINTN) desc->NumberOfPages * PAGE_SIZE;
-
- UINT64 Start = desc->PhysicalStart;
-
- next_desc = (EFI_MEMORY_DESCRIPTOR *)((UINT8 *)desc + DescriptorSize);
- if (!full) {
- while ((UINT8 *)next_desc < (UINT8 *)MemoryMap + MemoryMapSize) {
- mapping_size =(UINTN) desc->NumberOfPages * PAGE_SIZE;
- if ((desc->PhysicalStart + mapping_size) == (next_desc->PhysicalStart)) {
-
- if (desc->Type != next_desc->Type) {
- if (StrCmp(memory_type_to_str_OS_view(desc->Type),
- memory_type_to_str_OS_view(next_desc->Type)))
- break;
- }
-
- desc=next_desc;
- next_desc = (EFI_MEMORY_DESCRIPTOR *)((UINT8 *)next_desc + DescriptorSize);
- } else {
- break;
- }
- }
- }
-
- if (full) {
- CHAR16 str[ATTRIBUTE_STR_SIZE];
- Print(L"[#%02d] Type: %s Attr: %s\n", i++,
- memory_type_to_str(desc->Type), memory_attrs_to_str(str, desc->Attribute));
- Print(L" Phys: %016llx-%016llx\n", Start, Start + mapping_size - 1);
- }
- else {
- Print(L" [mem: %016llx-%016llx] %s\n", Start, desc->PhysicalStart + mapping_size - 1,
- memory_type_to_str_OS_view(desc->Type) );
- }
-
- desc = next_desc;
-}
-```
-
-Build program and copy it to UEFI folder.
-If we run in with the `full` option, everything would be like the last time:
-```
-FS0:\> MemoryInfo.efi full
-[#00] Type: EfiBootServicesCode Attr: UC WC WT WB
- Phys: 0000000000000000-0000000000000FFF
-[#01] Type: EfiConventionalMemory Attr: UC WC WT WB
- Phys: 0000000000001000-000000000009FFFF
-[#02] Type: EfiConventionalMemory Attr: UC WC WT WB
- Phys: 0000000000100000-00000000007FFFFF
-[#03] Type: EfiACPIMemoryNVS Attr: UC WC WT WB
- Phys: 0000000000800000-0000000000807FFF
-[#04] Type: EfiConventionalMemory Attr: UC WC WT WB
- Phys: 0000000000808000-000000000080FFFF
-[#05] Type: EfiACPIMemoryNVS Attr: UC WC WT WB
- Phys: 0000000000810000-00000000008FFFFF
-...
-```
-
-But if we run it without the `full` option, we will get a map similar to the that kernel displays in its boot log:
-```
-FS0:\> MemoryInfo.efi
- [mem: 0000000000000000-000000000009FFFF] usable
- [mem: 0000000000100000-00000000007FFFFF] usable
- [mem: 0000000000800000-0000000000807FFF] ACPI NVS
- [mem: 0000000000808000-000000000080FFFF] usable
- [mem: 0000000000810000-00000000008FFFFF] ACPI NVS
- [mem: 0000000000900000-00000000078EEFFF] usable
- [mem: 00000000078EF000-0000000007B6EFFF] reserved
- [mem: 0000000007B6F000-0000000007B7EFFF] ACPI data
- [mem: 0000000007B7F000-0000000007BFEFFF] ACPI NVS
- [mem: 0000000007BFF000-0000000007EF3FFF] usable
- [mem: 0000000007EF4000-0000000007F77FFF] reserved
- [mem: 0000000007F78000-0000000007FFFFFF] ACPI NVS
- [mem: 00000000FFC00000-00000000FFFFFFFF] reserved
-```
-Compare it with the actual kernel output:
-```
-BIOS-provided physical RAM map:
-BIOS-e820: [mem 0x0000000000000000-0x000000000009ffff] usable
-BIOS-e820: [mem 0x0000000000100000-0x00000000007fffff] usable
-BIOS-e820: [mem 0x0000000000800000-0x0000000000807fff] ACPI NVS
-BIOS-e820: [mem 0x0000000000808000-0x000000000080ffff] usable
-BIOS-e820: [mem 0x0000000000810000-0x00000000008fffff] ACPI NVS
-BIOS-e820: [mem 0x0000000000900000-0x00000000078eefff] usable
-BIOS-e820: [mem 0x00000000078ef000-0x0000000007b6efff] reserved
-BIOS-e820: [mem 0x0000000007b6f000-0x0000000007b7efff] ACPI data
-BIOS-e820: [mem 0x0000000007b7f000-0x0000000007bfefff] ACPI NVS
-BIOS-e820: [mem 0x0000000007bff000-0x0000000007ef3fff] usable
-BIOS-e820: [mem 0x0000000007ef4000-0x0000000007f77fff] reserved
-BIOS-e820: [mem 0x0000000007f78000-0x0000000007ffffff] ACPI NVS
-BIOS-e820: [mem 0x00000000ffc00000-0x00000000ffffffff] reserved
-```
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-11 13:58:58 +0000