main kernel startup, libc, console tty, asmops, build flags fixes
[bootcensus] / src / serial.c
diff --git a/src/serial.c b/src/serial.c
new file mode 100644 (file)
index 0000000..c707591
--- /dev/null
@@ -0,0 +1,321 @@
+#include <stdio.h>
+#include <string.h>
+#include "serial.h"
+#include "asmops.h"
+
+#define UART1_BASE     0x3f8
+#define UART2_BASE     0x2f8
+#define UART1_IRQ      4
+#define UART2_IRQ      3
+
+#define UART_DATA      0
+#define UART_INTR      1
+#define UART_DIVLO     0
+#define UART_DIVHI     1
+#define UART_FIFO      2
+#define UART_IID       2
+#define UART_LCTL      3
+#define UART_MCTL      4
+#define UART_LSTAT     5
+#define UART_MSTAT     6
+
+/* interrupt enable register bits */
+#define INTR_RECV      1
+#define INTR_SEND      2
+#define INTR_LSTAT     4
+#define INTR_DELTA     8
+
+/* fifo control register bits */
+#define FIFO_ENABLE            0x01
+#define FIFO_RECV_CLEAR        0x02
+#define FIFO_SEND_CLEAR        0x04
+#define FIFO_DMA               0x08
+#define FIFO_TRIG_4            0x40
+#define FIFO_TRIG_8            0x80
+#define FIFO_TRIG_14   0xc0
+
+/* interrupt id register bits */
+#define IID_PENDING            0x01
+#define IID_ID0                        0x02
+#define IID_ID1                        0x04
+#define IID_ID2                        0x08
+#define IID_FIFO_EN            0xc0
+
+#define IID_SOURCE             0xe
+
+#define IID_DELTA              0
+#define IID_SEND               0x2
+#define IID_RECV               0x4
+#define IID_FIFO               0xc
+#define IID_STATUS             0x6
+
+/* line control register bits */
+#define LCTL_BITS_8    0x03
+#define LCTL_STOP_2    0x04
+#define LCTL_DLAB      0x80
+#define LCTL_8N1       LCTL_BITS_8
+#define LCTL_8N2       (LCTL_BITS_8 | LCTL_STOP_2)
+
+/* modem control register bits */
+#define MCTL_DTR       0x01
+#define MCTL_RTS       0x02
+#define MCTL_OUT1      0x04
+#define MCTL_OUT2      0x08
+#define MCTL_LOOP      0x10
+
+/* line status register bits */
+#define LST_DRDY               0x01
+#define LST_ERR_OVER   0x02
+#define LST_ERR_PARITY 0x04
+#define LST_ERR_FRAME  0x08
+#define LST_ERR_BRK            0x10
+#define LST_TREG_EMPTY 0x20
+#define LST_TIDLE              0x40
+#define LST_ERROR              0x80
+
+/* modem status register bits */
+#define MST_DELTA_CTS  0x01
+#define MST_DELTA_DSR  0x02
+#define MST_TERI               0x04
+#define MST_DELTA_DCD  0x08
+#define MST_CTS                        0x10
+#define MST_DSR                        0x20
+#define MST_RING               0x40
+#define MST_DCD                        0x80
+
+/* interrupt controller stuff */
+#define PIC1_CMD_PORT  0x20
+#define PIC1_DATA_PORT 0x21
+#define PIC2_CMD_PORT  0xa0
+#define PIC2_DATA_PORT 0xa1
+#define OCW2_EOI               0x20
+
+#define COM_FMT_8N1            LCTL_8N1
+#define COM_FMT_8N2            LCTL_8N2
+
+struct serial_port {
+       int base, intr;
+       int blocking;
+
+       char inbuf[256];
+       int inbuf_ridx, inbuf_widx;
+};
+
+#define BNEXT(x)       (((x) + 1) & 0xff)
+#define BEMPTY(b)      (b##_ridx == b##_widx)
+
+/*
+static int have_recv(int base);
+static void recv_intr(void);*/
+
+static struct serial_port ports[2];
+static int num_open;
+
+static int uart_base[] = {UART1_BASE, UART2_BASE};
+/*static int uart_irq[] = {UART1_IRQ, UART2_IRQ};*/
+
+int ser_open(int pidx, int baud, unsigned int mode)
+{
+       unsigned short div = 115200 / baud;
+       int base; /*intr*/
+       unsigned int fmt;
+       /*int prev_if;*/
+
+       if(pidx < 0 || pidx > 1) {
+               printf("ser_open: invalid serial port: %d\n", pidx);
+               return -1;
+       }
+
+       if(ports[pidx].base) {
+               printf("ser_open: port %d already open!\n", pidx);
+               return -1;
+       }
+       memset(ports + pidx, 0, sizeof ports[pidx]);
+
+       base = uart_base[pidx];
+       /*intr = uart_irq[pidx] | 8;*/
+
+       if(mode & SER_8N2) {
+               fmt = COM_FMT_8N2;
+       } else {
+               fmt = COM_FMT_8N1;
+       }
+
+       /*prev_if = disable_intr();*/
+       /* TODO set interrupt handler */
+       /* unmask the appropriate interrupt */
+       /*outb(inb(PIC1_DATA_PORT) & ~(1 << uart_irq[pidx]), PIC1_DATA_PORT);*/
+
+       outb(LCTL_DLAB, base + UART_LCTL);
+       outb(div & 0xff, base + UART_DIVLO);
+       outb((div >> 8) & 0xff, base + UART_DIVHI);
+       outb(fmt, base + UART_LCTL);    /* fmt should be LCTL_8N1, LCTL_8N2 etc */
+       outb(FIFO_ENABLE | FIFO_SEND_CLEAR | FIFO_RECV_CLEAR, base + UART_FIFO);
+       outb(MCTL_DTR | MCTL_RTS | MCTL_OUT2, base + UART_MCTL);
+       /*outb(INTR_RECV, base + UART_INTR);
+
+       restore_intr(prev_if);*/
+
+       ports[pidx].base = base;
+       /*ports[pidx].intr = intr;*/
+       ports[pidx].blocking = 1;
+       ++num_open;
+       return pidx;
+}
+
+void ser_close(int fd)
+{
+       if(--num_open == 0) {
+               /*int prev_if = disable_intr();*/
+               /*outb(0, ports[fd].base + UART_INTR);*/
+               outb(0, ports[fd].base + UART_MCTL);
+               /*restore_intr(prev_if);*/
+       }
+
+       ports[fd].base = 0;
+}
+
+int ser_block(int fd)
+{
+       ports[fd].blocking = 1;
+       return 0;
+}
+
+int ser_nonblock(int fd)
+{
+       ports[fd].blocking = 0;
+       return 0;
+}
+
+int ser_pending(int fd)
+{
+       return !BEMPTY(ports[fd].inbuf);
+}
+
+/* if msec < 0: wait for ever */
+int ser_wait(int fd, long msec)
+{
+       int res;
+       while(!(res = ser_pending(fd))) {
+               /* TODO timeout */
+       }
+       return res;
+}
+
+static int can_send(int fd)
+{
+       int base = ports[fd].base;
+       return inb(base + UART_LSTAT) & LST_TREG_EMPTY;
+}
+
+void ser_putc(int fd, char c)
+{
+       int base = ports[fd].base;
+       while(!can_send(fd));
+       while((inb(base + UART_MSTAT) & MST_CTS) == 0);
+       outb(c, base + UART_DATA);
+}
+
+int ser_getc(int fd)
+{
+       struct serial_port *p = ports + fd;
+       int have, c = -1;
+
+       if(p->blocking) {
+               while(!(have = ser_pending(fd)));
+       } else {
+               have = ser_pending(fd);
+       }
+
+       if(have) {
+               c = p->inbuf[p->inbuf_ridx];
+               p->inbuf_ridx = BNEXT(p->inbuf_ridx);
+       }
+       return c;
+}
+
+int ser_write(int fd, const char *buf, int count)
+{
+       int n = count;
+       while(n--) {
+               ser_putc(fd, *buf++);
+       }
+       return count;
+}
+
+int ser_read(int fd, char *buf, int count)
+{
+       int c, n = 0;
+       while(n < count && (c = ser_getc(fd)) != -1) {
+               *buf++ = c;
+               ++n;
+       }
+       return n;
+}
+
+char *ser_getline(int fd, char *buf, int bsz)
+{
+       static char linebuf[512];
+       static int widx;
+       int i, rd, size, offs;
+
+       size = sizeof linebuf - widx;
+       while(size && (rd = ser_read(fd, linebuf + widx, size)) > 0) {
+               widx += rd;
+               size -= rd;
+       }
+
+       linebuf[widx] = 0;
+
+       for(i=0; i<widx; i++) {
+               if(linebuf[i] == '\r' || linebuf[i] == '\n') {
+                       size = i >= bsz ? bsz - 1 : i;
+                       memcpy(buf, linebuf, size);
+                       buf[size] = 0;
+
+                       offs = i + 1;
+                       memmove(linebuf, linebuf + offs, widx - offs);
+                       widx -= offs;
+                       return buf;
+               }
+       }
+       return 0;
+}
+
+#if 0
+static int have_recv(int base)
+{
+       unsigned short stat = inb(base + UART_LSTAT);
+       if(stat & LST_ERROR) {
+               printf("serial receive error\n");
+               panic();
+       }
+       return stat & LST_DRDY;
+}
+
+static void __interrupt __far recv_intr()
+{
+       int i, idreg, c;
+
+       for(i=0; i<2; i++) {
+               int base = uart_base[i];
+               struct serial_port *p = ports + i;
+
+               while(((idreg = inb(base + UART_IID)) & IID_PENDING) == 0) {
+                       while(have_recv(base)) {
+                               c = inb(base + UART_DATA);
+
+                               p->inbuf[p->inbuf_widx] = inb(base + UART_DATA);
+                               p->inbuf_widx = BNEXT(p->inbuf_widx);
+
+                               if(p->inbuf_widx == p->inbuf_ridx) {
+                                       /* we overflowed, drop the oldest */
+                                       p->inbuf_ridx = BNEXT(p->inbuf_ridx);
+                               }
+                       }
+               }
+       }
+
+       outb(OCW2_EOI, PIC1_CMD_PORT);
+}
+#endif