dev(device): implement VirtIO

See dev log for detail

3 files changed, 128 insertions, 2 deletions

diff --git a/include/drivers/plic.h b/include/drivers/plic.h
index 8e8d986..11e8c8a 100644
--- a/include/drivers/plic.h
+++ b/include/drivers/plic.h
@@ -1,7 +1,7 @@
 #pragma once
 #include "common/types.h"
 
-namespace PILC
+namespace PLIC
 {
     // Global initialization (executed only once by hart 0)
     void init();
diff --git a/include/drivers/uart.h b/include/drivers/uart.h
index cb84bde..26c2394 100644
--- a/include/drivers/uart.h
+++ b/include/drivers/uart.h
@@ -1,11 +1,35 @@
 #pragma once
 #include "common/types.h"
 
+#define UART0 0x10000000L
+#define RHR 0 // Receive Holding Register (read mode)
+#define THR 0 // Transmit Holding Register (write mode)
+#define IER 1 // Interrupt Enable Register
+#define FCR 2 // FIFO Control Register
+#define ISR 2 // Interrupt Status Register
+#define LCR 3 // Line Control Register
+#define LSR 5 // Line Status Register
+
+#define LSR_RX_READY 0x01 // input is waiting to be read from RHR
+#define LSR_TX_IDLE 0x20  // THR can accept another character to send
+
+#define UART_RX_BUF_SIZE 128
+
+// ANSI Escape Codes for Modern Terminal Colors
+#define ANSI_RESET "\033[0m"
+#define ANSI_RED "\033[31m"
+#define ANSI_GREEN "\033[32m"
+#define ANSI_YELLOW "\033[33m"
+#define ANSI_BLUE "\033[34m"
+#define ANSI_CLEAR "\033[2J\033[1;1H"
+
 namespace Drivers
 {
     void uart_init();
-    void uart_putc(char c);
+    void uart_intr();
+    int console_read(uint64 target, int len);
 
+    void uart_putc(char c);
     void uart_puts(const char *s);
     void uart_put_int(int value);
     void print_hex(uint64 value);
diff --git a/include/drivers/virtio.h b/include/drivers/virtio.h
new file mode 100644
index 0000000..308dae0
--- /dev/null
+++ b/include/drivers/virtio.h
@@ -0,0 +1,102 @@
+#pragma once
+#include "common/types.h"
+
+// VirtIO MMIO Base Address
+#define VIRTIO0 0x10001000
+
+// MMIO Registers (Modern / Version 2)
+#define VIRTIO_MMIO_MAGIC_VALUE 0x000
+#define VIRTIO_MMIO_VERSION 0x004
+#define VIRTIO_MMIO_DEVICE_ID 0x008
+#define VIRTIO_MMIO_VENDOR_ID 0x00c
+#define VIRTIO_MMIO_DEVICE_FEATURES 0x010
+#define VIRTIO_MMIO_DEVICE_FEATURES_SEL 0x014
+#define VIRTIO_MMIO_DRIVER_FEATURES 0x020
+#define VIRTIO_MMIO_DRIVER_FEATURES_SEL 0x024
+#define VIRTIO_MMIO_QUEUE_SEL 0x030
+#define VIRTIO_MMIO_QUEUE_NUM_MAX 0x034
+#define VIRTIO_MMIO_QUEUE_NUM 0x038
+#define VIRTIO_MMIO_QUEUE_READY 0x044
+#define VIRTIO_MMIO_QUEUE_NOTIFY 0x050
+#define VIRTIO_MMIO_INTERRUPT_STATUS 0x060
+#define VIRTIO_MMIO_INTERRUPT_ACK 0x064
+#define VIRTIO_MMIO_STATUS 0x070
+
+// 64-bit Queue Address Registers (Modern)
+#define VIRTIO_MMIO_QUEUE_DESC_LOW 0x080
+#define VIRTIO_MMIO_QUEUE_DESC_HIGH 0x084
+#define VIRTIO_MMIO_QUEUE_DRIVER_LOW 0x090
+#define VIRTIO_MMIO_QUEUE_DRIVER_HIGH 0x094
+#define VIRTIO_MMIO_QUEUE_DEVICE_LOW 0x0a0
+#define VIRTIO_MMIO_QUEUE_DEVICE_HIGH 0x0a4
+
+// Status Bits
+#define VIRTIO_CONFIG_S_ACKNOWLEDGE 1
+#define VIRTIO_CONFIG_S_DRIVER 2
+#define VIRTIO_CONFIG_S_DRIVER_OK 4
+#define VIRTIO_CONFIG_S_FEATURES_OK 8
+
+// Feature Bits
+#define VIRTIO_BLK_F_RO 5
+#define VIRTIO_BLK_F_SCSI 7
+#define VIRTIO_BLK_F_CONFIG_WCE 11
+#define VIRTIO_BLK_F_MQ 12
+#define VIRTIO_F_ANY_LAYOUT 27
+#define VIRTIO_RING_F_INDIRECT_DESC 28
+#define VIRTIO_RING_F_EVENT_IDX 29
+#define VIRTIO_F_VERSION_1 32
+
+// Descriptor Flags
+#define VRING_DESC_F_NEXT 1
+#define VRING_DESC_F_WRITE 2
+
+#define NUM_DESCS 8
+
+#define VIRTIO_BLK_T_IN 0
+#define VIRTIO_BLK_T_OUT 1
+
+// Device Configuration Layout (Offset 0x100)
+#define VIRTIO_MMIO_CONFIG 0x100
+
+namespace VirtIO
+{
+    struct VRingDesc
+    {
+        uint64 addr;
+        uint32 len;
+        uint16 flags;
+        uint16 next;
+    };
+
+    struct VRingAvail
+    {
+        uint16 flags;
+        uint16 idx;
+        uint16 ring[NUM_DESCS];
+    };
+
+    struct VRingUsedElem
+    {
+        uint32 id;
+        uint32 len;
+    };
+
+    struct VRingUsed
+    {
+        uint16 flags;
+        uint16 idx;
+        struct VRingUsedElem ring[NUM_DESCS];
+    };
+
+    struct __attribute__((packed)) BlockRequest
+    {
+        uint32 type; // 0=Read, 1=Write
+        uint32 reserved;
+        uint64 sector;
+    };
+
+    void init();
+    void intr();
+    void rw(int write, uint64 blockno, char *buf);
+    void test_rw();
+}
\ No newline at end of file