commit 20467d27baa757ed36617d2778d53fedd54d042d
parent e90acc16640527926b45080708ac11997f88b049
Author: Sylvia Ivory <git@sivory.net>
Date: Sun, 8 Mar 2026 21:57:16 -0700
Fix SD card code
Diffstat:
5 files changed, 56 insertions(+), 22 deletions(-)
diff --git a/include/emmc.c b/include/emmc.c
@@ -29,7 +29,7 @@ static u32 get_clock_divider(u32 base_clock) {
}
int div = -1;
- for (int fb = 31; fb >= 0; fb--) {
+ for (int fb = 30; fb >= 0; fb--) {
u32 bt = (1 << fb);
if (target_div & bt) {
diff --git a/pi/devices/sd.zig b/pi/devices/sd.zig
@@ -10,14 +10,17 @@ const Self = @This();
alloc: std.mem.Allocator,
-pub fn init(alloc: std.mem.Allocator) Self {
+pub fn init(alloc: std.mem.Allocator) vfs.Error!Self {
+ if (pi_sd.pi_sd_init() == -1) {
+ return vfs.Error.InitFailed;
+ }
return .{ .alloc = alloc };
}
pub fn read_sector(self: *const Self, sector: usize) vfs.Error!vfs.Sector {
_ = self;
- var buffer: [512]u8 = .{0} ** 512;
+ var buffer: [512]u8 align(512) = .{0} ** 512;
if (pi_sd.pi_sd_read(&buffer, sector, 1) == -1) {
return vfs.Error.ReadFailed;
}
@@ -26,8 +29,14 @@ pub fn read_sector(self: *const Self, sector: usize) vfs.Error!vfs.Sector {
}
pub fn read_sectors(self: *const Self, sector: usize, count: usize) vfs.Error![]vfs.Sector {
- var buffer = try self.alloc.alloc(u8, count * 512);
- if (pi_sd.pi_sd_read(@ptrCast(&buffer), sector, 1) == -1) {
+ const buffer = try self.alloc.allocWithOptions(
+ u8,
+ count * 512,
+ std.mem.Alignment.fromByteUnits(512),
+ null,
+ );
+
+ if (pi_sd.pi_sd_read(buffer.ptr, sector, count) == -1) {
return vfs.Error.ReadFailed;
}
diff --git a/pi/fs/vfs.zig b/pi/fs/vfs.zig
@@ -1,5 +1,7 @@
const std = @import("std");
+const uart = @import("../devices/mini-uart.zig");
+
// TODO; future expansion
// - File locking
// - Writing
@@ -16,6 +18,8 @@ pub const Error = error{
NotInitialized,
InvalidFileName,
+
+ InitFailed,
ReadFailed,
} || std.mem.Allocator.Error;
diff --git a/pi/root.zig b/pi/root.zig
@@ -101,3 +101,19 @@ export fn delay_s(s: u32) void {
export fn gpio_set_function(pin: u8, mode: u8) void {
devices.gpio.fn_sel(pin, @enumFromInt(@as(u3, @truncate(mode)))) catch {};
}
+export fn printk_0(a0: *u8) void {
+ const msg: [:0]u8 = @ptrCast(a0);
+ devices.mini_uart.print("{s}\n", .{msg});
+}
+export fn printk_1(a0: *u8, a1: i32) void {
+ const msg: [:0]u8 = @ptrCast(a0);
+ devices.mini_uart.print("{s} {d}\n", .{ msg, a1 });
+}
+export fn printk_2(a0: *u8, a1: i32, a2: i32) void {
+ const msg: [:0]u8 = @ptrCast(a0);
+ devices.mini_uart.print("{s} {d} {d}\n", .{ msg, a1, a2 });
+}
+export fn printk_3(a0: *u8, a1: i32, a2: i32, a3: i32) void {
+ const msg: [:0]u8 = @ptrCast(a0);
+ devices.mini_uart.print("{s} {d} {d} {d}\n", .{ msg, a1, a2, a3 });
+}
diff --git a/programs/fs.zig b/programs/fs.zig
@@ -7,7 +7,6 @@ const uart = pi.devices.mini_uart;
const Explorer = struct {
alloc: std.mem.Allocator,
- io_r: *std.Io.Reader,
io_w: *std.Io.Writer,
fs: vfs.FileSystem,
@@ -16,7 +15,7 @@ const Explorer = struct {
const Self = @This();
- pub fn init(alloc: std.mem.Allocator, fs: vfs.FileSystem, io_r: *std.Io.Reader, io_w: *std.Io.Writer) !Self {
+ pub fn init(alloc: std.mem.Allocator, fs: vfs.FileSystem, io_w: *std.Io.Writer) !Self {
var path: std.ArrayList([]const u8) = try .initCapacity(alloc, 1);
try path.append(alloc, "/");
@@ -25,25 +24,27 @@ const Explorer = struct {
.fs = fs,
.dir = try fs.open_root(),
.path = path,
- .io_r = io_r,
.io_w = io_w,
};
}
- pub fn start(self: *Self) !void {
- {
- const path = try std.mem.concat(self.alloc, u8, self.path.items);
- defer self.alloc.free(path);
- try self.io_w.print("[{s}] $ ", .{path});
- }
+ pub fn read_line(self: *Self) !void {
+ const path = try std.mem.concat(self.alloc, u8, self.path.items);
+ defer self.alloc.free(path);
+ try self.io_w.print("[{s}] $ ", .{path});
+
+ var line: std.ArrayList(u8) = try .initCapacity(self.alloc, 16);
+ defer line.deinit(self.alloc);
- while (try self.io_r.takeDelimiter('\n')) |line| {
- try self.parse_line(line);
+ // Wait until \n
+ while (true) {
+ const byte = uart.read_byte_sync();
+ if (byte == '\n') break;
- const path = try std.mem.concat(self.alloc, u8, self.path.items);
- defer self.alloc.free(path);
- try self.io_w.print("[{s}] $ ", .{path});
+ try line.append(self.alloc, byte);
}
+
+ try self.parse_line(line.items);
}
// I would like to apologize for this truly bad parser
@@ -65,6 +66,8 @@ const Explorer = struct {
try self.cat(entry);
} else if (std.mem.eql(u8, cmd, "help")) {
try self.io_w.print("Commands: ls, tree, cd, stat, cat, help\n", .{});
+ } else if (std.mem.eql(u8, cmd, "exit")) {
+ pi.reboot();
} else {
try self.io_w.print("\"{s}\": Command not found\n", .{cmd});
}
@@ -261,7 +264,7 @@ pub fn main() !void {
var fba: std.heap.FixedBufferAllocator = .init(&buffer);
const alloc = fba.allocator();
- var sd_card = sd.init(alloc);
+ var sd_card = try sd.init(alloc);
var fat_vfs: pi.fs.FatVFS = .init();
var vfs_disk = vfs.Disk.impl_by(&sd_card);
@@ -274,7 +277,9 @@ pub fn main() !void {
try vfs_fat.open(alloc, &vfs_disk, mbr.pte1.first_lba);
defer vfs_fat.close();
- var explorer = try Explorer.init(alloc, vfs_fat, &uart.reader, &uart.writer);
+ var explorer = try Explorer.init(alloc, vfs_fat, &uart.writer);
- try explorer.start();
+ while (true) {
+ try explorer.read_line();
+ }
}
