Changeset 152 for trunk/hal/x86_64/core/hal_apic.c

Timestamp:

Jul 6, 2017, 3:47:20 PM (6 years ago)

Author:

max@…

Message:

add a basic RS232 COM1 implementation

File:

• trunk/hal/x86_64/core/hal_apic.c (modified) (3 diffs)

trunk/hal/x86_64/core/hal_apic.c

@@ -114 +114 @@
 /* -------------------------------------------------------------------------- */
 
+#define BAUDRATE        19200
+#define BAUDRATE_DIV    (115200 / BAUDRATE)
+
+#define RS232_COM1_BASE 0x3F8
+
+#define RS232_DATA      0x00
+#define RS232_IER       0x01
+#       define IER_RD           0x01
+#       define IER_TBE          0x02
+#       define IER_ER_BRK       0x04
+#       define IER_RS232IN      0x08
+#define RS232_DIVLO     0x00    /* when DLAB = 1 */
+#define RS232_DIVHI     0x01    /* when DLAB = 1 */
+#define RS232_IIR       0x02
+#define RS232_LCR       0x03
+#       define LCR_DATA5        0x00
+#       define LCR_DATA6        0x01
+#       define LCR_DATA7        0x02
+#       define LCR_DATA8        0x03
+#       define LCR_TWOSTOP      0x04
+#       define LCR_PARITY       0x08
+#       define LCR_EVEN         0x10
+#       define LCR_STICK        0x20
+#       define LCR_DLAB         0x80
+#define RS232_MCR       0x04
+#       define MCR_DTR          0x01
+#       define MCR_RTS          0x02
+#       define MCR_ELL          0x04
+#       define MCR_IR           0x40
+#define RS232_LSR       0x05
+#       define LSR_DR           0x01
+#       define LSR_OVR          0x02
+#       define LSR_PE           0x04
+#       define LSR_FE           0x08
+#       define LSR_BRK          0x10
+#       define LSR_TBE          0x20
+#       define LSR_TE           0x40
+#define RS232_MSR       0x06
+#       define MSR_DCTS         0x01
+#       define MSR_DDSR         0x02
+#       define MSR_DRI          0x04
+#       define MSR_DDCD         0x08
+#       define MSR_CTS          0x10
+#       define MSR_DSR          0x20
+#       define MSR_RI           0x40
+#       define MSR_DCD          0x80
+
+#define RS232_SCRATCH   0x07
+
+static bool_t hal_com_received()
+{
+        return (in8(RS232_COM1_BASE + RS232_LSR) & LSR_DR) != 0;
+}
+
+static bool_t hal_com_transmit_empty()
+{
+        return (in8(RS232_COM1_BASE + RS232_LSR) & LSR_TBE) != 0;
+}
+
+char hal_com_read()
+{
+        while (!hal_com_received());
+        return in8(RS232_COM1_BASE + RS232_DATA);
+}
+
+void hal_com_send(char c)
+{
+        uint8_t mcr = in8(RS232_COM1_BASE + RS232_MCR);
+        out8(RS232_COM1_BASE + RS232_MCR, mcr | MCR_RTS);
+
+        while (!hal_com_transmit_empty());
+        out8(RS232_COM1_BASE + RS232_DATA, c);
+
+        out8(RS232_COM1_BASE + RS232_MCR, mcr);
+}
+
+static void hal_com_init()
+{
+        /* Disable all interrupts */
+        out8(RS232_COM1_BASE + RS232_IER, 0x00);
+
+        /* Set baudrate */
+        out8(RS232_COM1_BASE + RS232_LCR, LCR_DLAB);
+        out8(RS232_COM1_BASE + RS232_DIVLO, BAUDRATE_DIV);
+        out8(RS232_COM1_BASE + RS232_DIVHI, 0);
+
+        /* 8bits, no parity, one stop bit */
+        out8(RS232_COM1_BASE + RS232_LCR, LCR_DATA8);
+
+        /* Enable IRQs, DTR set, and also DSR */
+        out8(RS232_COM1_BASE + RS232_IER, IER_RD|IER_RS232IN);
+        out8(RS232_COM1_BASE + RS232_MCR, MCR_DTR|MCR_IR);
+        out8(RS232_COM1_BASE + RS232_MSR, MSR_DSR);
+}
+
+/* -------------------------------------------------------------------------- */
+
 size_t ioapic_pins __in_kdata = 0;
 paddr_t ioapic_pa __in_kdata = 0;
@@ -193 +290 @@
         x86_printf("IOAPICPINS: #%z\n", ioapic_pins);
 
-        /* Now, enable the keyboard */
+        /* Now, enable the com1 port and the keyboard */
+        hal_ioapic_set_entry(IRQ_COM1, IOAPIC_COM1_VECTOR, 0);
         hal_ioapic_set_entry(IRQ_KEYBOARD, IOAPIC_KEYBOARD_VECTOR, 0);
 }
@@ -309 +407 @@
         /* Enable the IOAPIC */
         hal_ioapic_init();
-}
-
+
+        /* Enable the Serial Port */
+        hal_com_init();
+
+        hal_com_send('p');
+        hal_com_send('d');
+        hal_com_send('\n');
+}
+