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-rw-r--r--src/kernel/fdt.cc273
1 files changed, 0 insertions, 273 deletions
diff --git a/src/kernel/fdt.cc b/src/kernel/fdt.cc
deleted file mode 100644
index ae09c84..0000000
--- a/src/kernel/fdt.cc
+++ /dev/null
@@ -1,273 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2026 Richard Qin
- * LumeOS - FDT Parser
- *
- * Parses the Flattened Device Tree to discover hardware.
- * Populates g_devices for use by all drivers.
- */
-#include "common/types.h"
-#include "kernel/fdt.h"
-#include "lib/string.h"
-
-// Global device registry
-DeviceRegistry g_devices;
-
-// Keep g_dtb_addr for PMM to protect DTB pages
-// g_dtb_addr is defined in entry.S, g_uart_base in config.cc
-extern "C" uint64 g_dtb_addr;
-extern uint64 g_uart_base;
-
-static inline uint32 bswap(uint32 x)
-{
- return ((x & 0xFF) << 24) | ((x & 0xFF00) << 8) |
- ((x & 0xFF0000) >> 8) | ((x >> 24) & 0xFF);
-}
-
-struct fdt_header
-{
- uint32 magic;
- uint32 totalsize;
- uint32 off_dt_struct;
- uint32 off_dt_strings;
- uint32 off_mem_rsvmap;
- uint32 version;
- uint32 last_comp_version;
- uint32 boot_cpuid_phys;
- uint32 size_dt_strings;
- uint32 size_dt_struct;
-};
-
-#define FDT_MAGIC 0xd00dfeed
-#define FDT_BEGIN_NODE 1
-#define FDT_END_NODE 2
-#define FDT_PROP 3
-#define FDT_NOP 4
-#define FDT_END 9
-
-// Check if 'str' starts with 'prefix'
-static bool starts_with(const char *str, const char *prefix)
-{
- while (*prefix)
- {
- if (*str != *prefix)
- return false;
- str++;
- prefix++;
- }
- return true;
-}
-
-// Check if 'haystack' contains 'needle' as a substring within 'len' bytes
-// (compatible strings may have multiple null-separated entries)
-static bool compat_match(const uint8 *data, uint32 len, const char *needle)
-{
- uint32 nlen = strlen(needle);
- for (uint32 i = 0; i + nlen <= len; i++)
- {
- if (memcmp(data + i, needle, nlen) == 0)
- return true;
- }
- return false;
-}
-
-// Add a MMIO region to the registry (avoids duplicates)
-static void add_mmio_region(uint64 base, uint64 size)
-{
- if (base == 0 || size == 0)
- return;
- // Only track I/O regions below RAM
- if (base >= 0x80000000ULL)
- return;
- if (g_devices.mmio_count >= DeviceRegistry::MAX_MMIO)
- return;
-
- // Check for overlap/duplicate
- for (int i = 0; i < g_devices.mmio_count; i++)
- {
- if (g_devices.mmio_regions[i].base == base)
- return;
- }
-
- g_devices.mmio_regions[g_devices.mmio_count].base = base;
- g_devices.mmio_regions[g_devices.mmio_count].size = size;
- g_devices.mmio_count++;
-}
-
-void fdt_parse(uint64 dtb)
-{
- // Clear registry
- memset(&g_devices, 0, sizeof(g_devices));
-
- if (dtb == 0)
- return;
-
- g_dtb_addr = dtb;
-
- struct fdt_header *header = (struct fdt_header *)dtb;
- if (bswap(header->magic) != FDT_MAGIC)
- return;
-
- uint8 *struct_ptr = (uint8 *)(dtb + bswap(header->off_dt_struct));
- char *strings_ptr = (char *)(dtb + bswap(header->off_dt_strings));
-
- // Parsing state
- char current_node_name[64];
- current_node_name[0] = '\0';
-
- // Per-node state
- uint64 current_reg_addr = 0;
- uint64 current_reg_size = 0;
- uint32 current_irq = 0;
- const uint8 *current_compat = nullptr;
- uint32 current_compat_len = 0;
- bool has_reg = false;
- bool has_compat = false;
- // bool has_irq = false; // Unused
-
- // Depth tracking (for #address-cells / #size-cells)
- // Default for root: 2 address-cells, 2 size-cells
- int depth = 0;
-
- while (1)
- {
- uint32 token = bswap(*(uint32 *)struct_ptr);
- struct_ptr += 4;
-
- if (token == FDT_END)
- break;
- if (token == FDT_NOP)
- continue;
-
- if (token == FDT_BEGIN_NODE)
- {
- // Save node name
- // char *name = (char *)struct_ptr;
- int i = 0;
- while (*struct_ptr != 0 && i < 63)
- {
- current_node_name[i++] = *struct_ptr;
- struct_ptr++;
- }
- current_node_name[i] = '\0';
- while (*struct_ptr != 0)
- struct_ptr++;
- struct_ptr++;
- struct_ptr = (uint8 *)(((uint64)struct_ptr + 3) & ~3);
-
- // Reset per-node state
- current_reg_addr = 0;
- current_reg_size = 0;
- current_irq = 0;
- current_compat = nullptr;
- current_compat_len = 0;
- has_reg = false;
- has_compat = false;
- // has_irq = false;
-
- depth++;
- }
- else if (token == FDT_END_NODE)
- {
- // Process the node we just finished
- if (has_reg && has_compat)
- {
- // UART: ns16550a
- if (compat_match(current_compat, current_compat_len, "ns16550"))
- {
- g_devices.uart.base_addr = current_reg_addr;
- g_devices.uart.size = current_reg_size ? current_reg_size : 0x100;
- g_devices.uart.irq = current_irq;
- add_mmio_region(current_reg_addr, g_devices.uart.size);
- }
- // PLIC
- else if (compat_match(current_compat, current_compat_len, "plic"))
- {
- g_devices.plic.base_addr = current_reg_addr;
- g_devices.plic.size = current_reg_size ? current_reg_size : 0x4000000;
- g_devices.plic.irq = 0;
- add_mmio_region(current_reg_addr, g_devices.plic.size);
- }
- // CLINT
- else if (compat_match(current_compat, current_compat_len, "clint"))
- {
- g_devices.clint.base_addr = current_reg_addr;
- g_devices.clint.size = current_reg_size ? current_reg_size : 0x10000;
- g_devices.clint.irq = 0;
- add_mmio_region(current_reg_addr, g_devices.clint.size);
- }
- // VirtIO
- else if (compat_match(current_compat, current_compat_len, "virtio"))
- {
- if (g_devices.virtio_count < DeviceRegistry::MAX_VIRTIO)
- {
- int idx = g_devices.virtio_count++;
- g_devices.virtio[idx].base_addr = current_reg_addr;
- g_devices.virtio[idx].size = current_reg_size ? current_reg_size : 0x1000;
- g_devices.virtio[idx].irq = current_irq;
- add_mmio_region(current_reg_addr, g_devices.virtio[idx].size);
- }
- }
- }
-
- // Memory node: name starts with "memory"
- if (has_reg && starts_with(current_node_name, "memory"))
- {
- g_devices.mem_base = current_reg_addr;
- g_devices.mem_size = current_reg_size;
- }
-
- depth--;
- }
- else if (token == FDT_PROP)
- {
- uint32 len = bswap(*(uint32 *)struct_ptr);
- struct_ptr += 4;
- uint32 nameoff = bswap(*(uint32 *)struct_ptr);
- struct_ptr += 4;
-
- char *name = strings_ptr + nameoff;
- uint8 *data = struct_ptr;
-
- struct_ptr += len;
- struct_ptr = (uint8 *)(((uint64)struct_ptr + 3) & ~3);
-
- if (strcmp(name, "reg") == 0 && len >= 8)
- {
- // Assume 2 address-cells, 2 size-cells (standard for QEMU virt)
- uint32 hi = bswap(*(uint32 *)data);
- uint32 lo = bswap(*(uint32 *)(data + 4));
- current_reg_addr = ((uint64)hi << 32) | lo;
-
- if (len >= 16)
- {
- uint32 shi = bswap(*(uint32 *)(data + 8));
- uint32 slo = bswap(*(uint32 *)(data + 12));
- current_reg_size = ((uint64)shi << 32) | slo;
- }
- has_reg = true;
- }
- else if (strcmp(name, "compatible") == 0)
- {
- current_compat = data;
- current_compat_len = len;
- has_compat = true;
- }
- else if (strcmp(name, "interrupts") == 0 && len >= 4)
- {
- current_irq = bswap(*(uint32 *)data);
- // has_irq = true;
- }
- else if (strcmp(name, "interrupts-extended") == 0 && len >= 8)
- {
- // interrupts-extended = <&phandle irq_num>
- // IRQ number is typically the second cell
- current_irq = bswap(*(uint32 *)(data + 4));
- // has_irq = true;
- }
- }
- }
-
- // Legacy compat
- g_uart_base = g_devices.uart.base_addr;
-} \ No newline at end of file
generated by cgit v1.2.3 (git 2.46.0) at 2026-10-29 04:24:03 +0000