Changeset 152

Timestamp:

Jul 6, 2017, 3:47:20 PM (7 years ago)

Author:

max@…

Message:

add a basic RS232 COM1 implementation

Location:

trunk/hal/x86_64/core

Files:

• hal_apic.c (modified) (3 diffs)
• hal_apic.h (modified) (1 diff)
• hal_init.c (modified) (1 diff)
• hal_interrupt.c (modified) (2 diffs)
• hal_kentry.S (modified) (3 diffs)
• hal_segmentation.h (modified) (2 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');
+}
+

trunk/hal/x86_64/core/hal_apic.h

@@ -21 +21 @@
 
 #ifndef x86_ASM
+char hal_com_read();
+void hal_com_send(char c);
+
 void hal_ioapic_disable_entry(uint8_t index);
 void hal_ioapic_set_entry(uint8_t index, uint8_t vec, uint8_t dest);

trunk/hal/x86_64/core/hal_init.c

@@ -296 +296 @@
         hal_enable_irq(&dummy);
 
+        while (1);
+
         kernel_init(&btinfo);
 

trunk/hal/x86_64/core/hal_interrupt.c

@@ -27 +27 @@
 
 #include <hal_kentry.h>
+#include <hal_apic.h>
 #include <hal_internal.h>
 
@@ -37 +38 @@
 {
         x86_printf("-> got timer: rip=%Z\n", tf->tf_rip);
+        hal_com_send('h');
+        return;
+}
+
+/* -------------------------------------------------------------------------- */
+
+/*
+ * Serial Port (COM1) interrupt
+ */
+void hal_com1_intr(struct trapframe *tf)
+{
+        char c = hal_com_read();
+
+        x86_printf("-> got com '%c'\n", c);
         return;
 }

trunk/hal/x86_64/core/hal_kentry.S

@@ -36 +36 @@
         .globl  hal_exception_entry
         .globl  hal_timer_intr
+        .globl  hal_com1_intr
         .globl  hal_keyboard_intr
         .type   hal_exception_entry, @function
         .type   hal_timer_intr, @function
+        .type   hal_com1_intr, @function
         .type   hal_keyboard_intr, @function
 
@@ -133 +135 @@
         movq    %rsp,%rdi
         call    hal_timer_intr
+
+        movq    lapic_va(%rip),%rax
+        movl    $0,LAPIC_EOI(%rax)
+
+        INTR_RESTORE_REGS
+        addq    $16,%rsp
+        iretq
+
+ASM_ENTRY(x86_ioapic_com1)
+        pushq   $0
+        pushq   $T_ASTFLT
+        INTR_SAVE_REGS
+
+        movq    %rsp,%rdi
+        call    hal_com1_intr
 
         movq    lapic_va(%rip),%rax
@@ -247 +264 @@
 
         .quad   x86_lapic_timer
+        .quad   x86_ioapic_com1
         .quad   x86_ioapic_keyboard
 

trunk/hal/x86_64/core/hal_segmentation.h

@@ -195 +195 @@
 
 #define DYNVEC_MIN      CPUVEC_MAX
-#define DYNVEC_MAX      (DYNVEC_MIN + 6)
+#define DYNVEC_MAX      (DYNVEC_MIN + 7)
 
 #define VECTOR_APIC_SPURIOU     (DYNVEC_MIN + 0)
@@ -202 +202 @@
 #define VECTOR_APIC_XCU_PTI     (DYNVEC_MIN + 3)
 
-/* debug only, will be removed soon */
+/* debug only, will be moved soon */
 #define LAPIC_TIMER_VECTOR      (DYNVEC_MIN + 4)
-#define IOAPIC_KEYBOARD_VECTOR  (DYNVEC_MIN + 5)
+#define IOAPIC_COM1_VECTOR      (DYNVEC_MIN + 5)
+#define IOAPIC_KEYBOARD_VECTOR  (DYNVEC_MIN + 6)
 
 #define NIDT    256     /* total number of IDT entries */
 
+