add fs

programs/boot.vc5asm

@@ -48,6 +48,25 @@ _start:
     mov r0, 0
     mov [counter], r0
 
+    mov r1, 0
+.loop_body:
+    mov r2, r1
+    add r2, 32
+
+    add rsp, 4
+    mov [rsp-4], r1
+    mov [rsp-2], r2
+    call term_putc
+    mov r1, [rsp-4]
+    sub rsp, 4
+
+    add r1, 1
+.loop_cond:
+    cmp r1, 127 - 32
+    mov r0, rfl
+    and r0, fl_lt
+    jnz r0, .loop_body
+
 main_loop:
     hlt
     jmp main_loop
@@ -76,7 +95,7 @@ key_press_int:
     and r2, fl_eq
     jnz r2, .print_dot
 
-    add r1, 61 ; scancode letter -> ascii
+    add r1, 93 ; scancode letter -> ascii
     mov [rsp], r1
     add rsp, 2
     call term_putc

src/fs.cpp

@@ -0,0 +1,75 @@
+#include "fs.hpp"
+#include <cstdint>
+
+namespace vc5::filesys {
+
+constexpr auto Ok = Status::Ok;
+
+using BlockData = std::array<uint8_t, block_size>;
+
+void Fs::init()
+{
+    m_super = SuperBlockData {
+        .block_bitmap = {},
+        .inode_bitmap = {},
+        .inode_blocks = {},
+    };
+    write_superblock();
+}
+
+Status Fs::make_directory()
+{
+    uint16_t id;
+    if (auto result = next_inode_id(id); result != Ok) {
+        return result;
+    }
+
+    auto node = INodeData {
+        .id = id,
+        .flags = static_cast<uint16_t>(INodeType::Directory),
+        .blocks_count = 0,
+        .blocks = {},
+    };
+}
+
+Status Fs::write_new_inode(INodeData& data)
+{
+    uint16_t block_id = data.id / inodes_per_block;
+    uint16_t offset = data.id % inodes_per_block * inode_size;
+
+    BlockData block;
+    m_disk->read(&block[0], block_id);
+}
+
+Status Fs::next_inode_id(uint16_t& id)
+{
+    for (uint16_t map_idx = 0; map_idx < sb_inode_bitmap_count; ++map_idx) {
+        auto& map = m_super.inode_bitmap[map_idx];
+
+        for (uint16_t bit_idx = 0; bit_idx < 16; ++bit_idx) {
+
+            if ((map >> bit_idx & 1) == 0) {
+                id = map_idx * sb_inode_bitmap_count + bit_idx;
+                return Ok;
+            }
+        }
+    }
+    return Status::INodeAllocFail;
+}
+
+Status Fs::read_superblock()
+{
+    BlockData block;
+    m_disk->read(&block[0], super_block_location);
+    m_super = *reinterpret_cast<SuperBlockData*>(&block[0]);
+    return Ok;
+}
+
+Status Fs::write_superblock()
+{
+    m_disk->write(
+        reinterpret_cast<const uint8_t*>(&m_super), super_block_location);
+    return Ok;
+}
+
+}

src/fs.hpp

@@ -0,0 +1,73 @@
+#pragma once
+
+#include "block_device.hpp"
+#include <cstddef>
+#include <cstdint>
+
+namespace vc5::filesys {
+
+enum class Status : uint16_t {
+    Ok,
+    INodeAllocFail,
+};
+
+constexpr uint16_t block_size = 0x200;
+constexpr uint16_t name_max_len = 255;
+
+struct DirEntryData {
+    uint16_t inode;
+    uint16_t name_len;
+    std::array<uint8_t, name_max_len> name;
+};
+
+enum class INodeType : uint16_t {
+    File = 0,
+    Directory = 1,
+    Symlink = 2,
+};
+
+constexpr uint16_t inode_size = 32;
+constexpr uint16_t inodes_per_block = block_size / inode_size;
+constexpr uint16_t inode_blocks_count = 8;
+
+struct INodeData {
+    uint16_t id;
+    uint16_t flags;
+    uint16_t blocks_count;
+    std::array<uint16_t, inode_blocks_count> blocks;
+};
+
+constexpr uint16_t super_block_location = 0x400;
+constexpr uint16_t sb_block_bitmap_count = 8;
+constexpr uint16_t sb_inode_bitmap_count = 8;
+constexpr uint16_t sb_inode_blocks_count = 16;
+
+struct SuperBlockData {
+    std::array<uint16_t, sb_block_bitmap_count> block_bitmap;
+    std::array<uint16_t, sb_inode_bitmap_count> inode_bitmap;
+    std::array<uint16_t, sb_inode_blocks_count> inode_blocks;
+};
+
+class Fs {
+public:
+    explicit Fs(BlockDevice& disk)
+        : m_disk(&disk)
+    {
+    }
+
+    void init();
+
+private:
+    Status make_directory();
+
+    Status write_new_inode(INodeData& data);
+    Status next_inode_id(uint16_t& id);
+
+    Status read_superblock();
+    Status write_superblock();
+
+    BlockDevice* m_disk;
+    SuperBlockData m_super;
+};
+
+}

src/io_device.cpp

@@ -20,6 +20,21 @@ constexpr uint64_t char_data(uint8_t ch)
     switch (ch) {
             // clang-format off
         case ' ': return 0x0000000000000000;
+        case '!': return 0x0018181818001818;
+        case '"': return 0x0066660000000000;
+        case '#': return 0x00247e24247e2400;
+        case '$': return 0x00187e6218467e18;
+        case '%': return 0x0022562c18346a44;
+        case '&': return 0x00784c38724a4638;
+        case '\'': return 0x0018181800000000;
+        case '(': return 0x000c18303030180c;
+        case ')': return 0x0030180c0c0c1830;
+        case '*': return 0x0000241818240000;
+        case '+': return 0x000018187e7e1818;
+        case ',': return 0x0000000000181830;
+        case '-': return 0x000000007e7e0000;
+        case '.': return 0x0000000000181800;
+        case '/': return 0x0002060c18306040;
 
         case '0': return 0x003C666E7666663C;
         case '1': return 0x001838181818183C;
@@ -32,6 +47,14 @@ constexpr uint64_t char_data(uint8_t ch)
         case '8': return 0x003C66663C66663C;
         case '9': return 0x003C66663E06663C;
 
+        case ':': return 0x0018180000181800;
+        case ';': return 0x0000181800181830;
+        case '<': return 0x00060c1830180c06;
+        case '=': return 0x00007e7e007e7e00;
+        case '>': return 0x006030180c183060;
+        case '?': return 0x003e660c18001818;
+        case '@': return 0x003c664a564e603c;
+
         case 'A': return 0x00187E66667E6666;
         case 'B': return 0x00787E667C667E7C;
         case 'C': return 0x003C7E6060607E3C;
@@ -59,7 +82,42 @@ constexpr uint64_t char_data(uint8_t ch)
         case 'Y': return 0x0066663C18181818;
         case 'Z': return 0x007E7E0C18307E7E;
 
-        case ':': return 0x0018180000181800;
+        case '[': return 0x003c30303030303c;
+        case '\\': return 0x00406030180c0602;
+        case ']': return 0x003c0c0c0c0c0c3c;
+        case '^': return 0x0010386c44000000;
+        case '_': return 0x00000000000000ff;
+        case '`': return 0x0030181800000000;
+        case 'a': return 0x0000003c023e423e;
+        case 'b': return 0x004040407c42427c;
+        case 'c': return 0x000000003c40403c;
+        case 'd': return 0x000202023e42423e;
+        case 'e': return 0x0000003c427c403c;
+        case 'f': return 0x00000c103c101010;
+        case 'g': return 0x003e645840784438;
+        case 'h': return 0x0020202038242424;
+        case 'i': return 0x0000181800181818;
+        case 'j': return 0x000606000606361c;
+        case 'k': return 0x0020202c3830382c;
+        case 'l': return 0x003010101010100c;
+        case 'm': return 0x000000203e2a2a2a;
+        case 'n': return 0x0000000038242424;
+        case 'o': return 0x0000000018242418;
+        case 'p': return 0x0000001c223c2020;
+        case 'q': return 0x00000018241c0404;
+        case 'r': return 0x0000002038242020;
+        case 's': return 0x0000003840380438;
+        case 't': return 0x0000103c1010100c;
+        case 'u': return 0x000000002424241e;
+        case 'v': return 0x0000002424243c18;
+        case 'w': return 0x0000000063222a3e;
+        case 'x': return 0x000000663c183c66;
+        case 'y': return 0x00000024241c0438;
+        case 'z': return 0x0000003e060c183e;
+        case '{': return 0x000c18183018180c;
+        case '|': return 0x1818181818181818;
+        case '}': return 0x003018180c181830;
+        case '~': return 0x0000307a5e0c0000;
 
         default:  return 0x55AA55AA55AA55AA;
             // clang-format on

src/vm.cpp

@@ -195,6 +195,11 @@ struct InsReader {
     VM* vm;
     uint16_t ins;
 
+    auto op() -> Op
+    {
+        return static_cast<Op>(ins & 0b11'1111);
+    }
+
     auto to_u16() const -> uint16_t
     {
         return ins;
@@ -277,7 +282,8 @@ int VM::run_instruction()
         return -1;
 
     auto ins = InsReader(*this);
-    auto op = static_cast<Op>(ins.to_u16() & 0b11'1111);
+    auto op = ins.op();
+
     std::println(
         "    [{: >3x}]: 0x{:04x} {: <6} {:04b} {:04b} {:04b} {:04b}    {:04x}",
         ip,