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-rw-r--r--roms/seabios/src/serial.c317
1 files changed, 317 insertions, 0 deletions
diff --git a/roms/seabios/src/serial.c b/roms/seabios/src/serial.c
new file mode 100644
index 00000000..88349c8a
--- /dev/null
+++ b/roms/seabios/src/serial.c
@@ -0,0 +1,317 @@
+// 16bit code to handle serial and printer services.
+//
+// Copyright (C) 2008,2009 Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2002 MandrakeSoft S.A.
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#include "biosvar.h" // SET_BDA
+#include "bregs.h" // struct bregs
+#include "hw/serialio.h" // SEROFF_IER
+#include "output.h" // debug_enter
+#include "romfile.h" // romfile_loadint
+#include "stacks.h" // yield
+#include "util.h" // serial_setup
+
+
+/****************************************************************
+ * COM ports
+ ****************************************************************/
+
+static u16
+detect_serial(u16 port, u8 timeout, u8 count)
+{
+ if (CONFIG_DEBUG_SERIAL && port == CONFIG_DEBUG_SERIAL_PORT
+ && !romfile_loadint("etc/advertise-serial-debug-port", 1))
+ return 0;
+ outb(0x02, port+SEROFF_IER);
+ u8 ier = inb(port+SEROFF_IER);
+ if (ier != 0x02)
+ return 0;
+ u8 iir = inb(port+SEROFF_IIR);
+ if ((iir & 0x3f) != 0x02)
+ return 0;
+
+ outb(0x00, port+SEROFF_IER);
+ SET_BDA(port_com[count], port);
+ SET_BDA(com_timeout[count], timeout);
+ return 1;
+}
+
+void
+serial_setup(void)
+{
+ if (! CONFIG_SERIAL)
+ return;
+ dprintf(3, "init serial\n");
+
+ u16 count = 0;
+ count += detect_serial(PORT_SERIAL1, 0x0a, count);
+ count += detect_serial(PORT_SERIAL2, 0x0a, count);
+ count += detect_serial(PORT_SERIAL3, 0x0a, count);
+ count += detect_serial(PORT_SERIAL4, 0x0a, count);
+ dprintf(1, "Found %d serial ports\n", count);
+
+ // Equipment word bits 9..11 determing # serial ports
+ set_equipment_flags(0xe00, count << 9);
+}
+
+static u16
+getComAddr(struct bregs *regs)
+{
+ if (regs->dx >= 4) {
+ set_invalid(regs);
+ return 0;
+ }
+ u16 addr = GET_BDA(port_com[regs->dx]);
+ if (! addr)
+ set_invalid(regs);
+ return addr;
+}
+
+// SERIAL - INITIALIZE PORT
+static void
+handle_1400(struct bregs *regs)
+{
+ u16 addr = getComAddr(regs);
+ if (!addr)
+ return;
+ outb(inb(addr+SEROFF_LCR) | 0x80, addr+SEROFF_LCR);
+ if ((regs->al & 0xE0) == 0) {
+ outb(0x17, addr+SEROFF_DLL);
+ outb(0x04, addr+SEROFF_DLH);
+ } else {
+ u16 val16 = 0x600 >> ((regs->al & 0xE0) >> 5);
+ outb(val16 & 0xFF, addr+SEROFF_DLL);
+ outb(val16 >> 8, addr+SEROFF_DLH);
+ }
+ outb(regs->al & 0x1F, addr+SEROFF_LCR);
+ regs->ah = inb(addr+SEROFF_LSR);
+ regs->al = inb(addr+SEROFF_MSR);
+ set_success(regs);
+}
+
+// SERIAL - WRITE CHARACTER TO PORT
+static void
+handle_1401(struct bregs *regs)
+{
+ u16 addr = getComAddr(regs);
+ if (!addr)
+ return;
+ u32 end = irqtimer_calc_ticks(GET_BDA(com_timeout[regs->dx]));
+ for (;;) {
+ u8 lsr = inb(addr+SEROFF_LSR);
+ if ((lsr & 0x60) == 0x60) {
+ // Success - can write data
+ outb(regs->al, addr+SEROFF_DATA);
+ // XXX - reread lsr?
+ regs->ah = lsr;
+ break;
+ }
+ if (irqtimer_check(end)) {
+ // Timed out - can't write data.
+ regs->ah = lsr | 0x80;
+ break;
+ }
+ yield();
+ }
+ set_success(regs);
+}
+
+// SERIAL - READ CHARACTER FROM PORT
+static void
+handle_1402(struct bregs *regs)
+{
+ u16 addr = getComAddr(regs);
+ if (!addr)
+ return;
+ u32 end = irqtimer_calc_ticks(GET_BDA(com_timeout[regs->dx]));
+ for (;;) {
+ u8 lsr = inb(addr+SEROFF_LSR);
+ if (lsr & 0x01) {
+ // Success - can read data
+ regs->al = inb(addr+SEROFF_DATA);
+ regs->ah = lsr;
+ break;
+ }
+ if (irqtimer_check(end)) {
+ // Timed out - can't read data.
+ regs->ah = lsr | 0x80;
+ break;
+ }
+ yield();
+ }
+ set_success(regs);
+}
+
+// SERIAL - GET PORT STATUS
+static void
+handle_1403(struct bregs *regs)
+{
+ u16 addr = getComAddr(regs);
+ if (!addr)
+ return;
+ regs->ah = inb(addr+SEROFF_LSR);
+ regs->al = inb(addr+SEROFF_MSR);
+ set_success(regs);
+}
+
+static void
+handle_14XX(struct bregs *regs)
+{
+ set_unimplemented(regs);
+}
+
+// INT 14h Serial Communications Service Entry Point
+void VISIBLE16
+handle_14(struct bregs *regs)
+{
+ debug_enter(regs, DEBUG_HDL_14);
+ if (! CONFIG_SERIAL) {
+ handle_14XX(regs);
+ return;
+ }
+
+ switch (regs->ah) {
+ case 0x00: handle_1400(regs); break;
+ case 0x01: handle_1401(regs); break;
+ case 0x02: handle_1402(regs); break;
+ case 0x03: handle_1403(regs); break;
+ default: handle_14XX(regs); break;
+ }
+}
+
+
+/****************************************************************
+ * LPT ports
+ ****************************************************************/
+
+static u16
+detect_parport(u16 port, u8 timeout, u8 count)
+{
+ // clear input mode
+ outb(inb(port+2) & 0xdf, port+2);
+
+ outb(0xaa, port);
+ if (inb(port) != 0xaa)
+ // Not present
+ return 0;
+ SET_BDA(port_lpt[count], port);
+ SET_BDA(lpt_timeout[count], timeout);
+ return 1;
+}
+
+void
+lpt_setup(void)
+{
+ if (! CONFIG_LPT)
+ return;
+ dprintf(3, "init lpt\n");
+
+ u16 count = 0;
+ count += detect_parport(PORT_LPT1, 0x14, count);
+ count += detect_parport(PORT_LPT2, 0x14, count);
+ dprintf(1, "Found %d lpt ports\n", count);
+
+ // Equipment word bits 14..15 determing # parallel ports
+ set_equipment_flags(0xc000, count << 14);
+}
+
+static u16
+getLptAddr(struct bregs *regs)
+{
+ if (regs->dx >= 3) {
+ set_invalid(regs);
+ return 0;
+ }
+ u16 addr = GET_BDA(port_lpt[regs->dx]);
+ if (! addr)
+ set_invalid(regs);
+ return addr;
+}
+
+// INT 17 - PRINTER - WRITE CHARACTER
+static void
+handle_1700(struct bregs *regs)
+{
+ u16 addr = getLptAddr(regs);
+ if (!addr)
+ return;
+
+ u32 end = irqtimer_calc_ticks(GET_BDA(lpt_timeout[regs->dx]));
+
+ outb(regs->al, addr);
+ u8 val8 = inb(addr+2);
+ outb(val8 | 0x01, addr+2); // send strobe
+ udelay(5);
+ outb(val8 & ~0x01, addr+2);
+
+ for (;;) {
+ u8 v = inb(addr+1);
+ if (!(v & 0x40)) {
+ // Success
+ regs->ah = v ^ 0x48;
+ break;
+ }
+ if (irqtimer_check(end)) {
+ // Timeout
+ regs->ah = (v ^ 0x48) | 0x01;
+ break;
+ }
+ yield();
+ }
+
+ set_success(regs);
+}
+
+// INT 17 - PRINTER - INITIALIZE PORT
+static void
+handle_1701(struct bregs *regs)
+{
+ u16 addr = getLptAddr(regs);
+ if (!addr)
+ return;
+
+ u8 val8 = inb(addr+2);
+ outb(val8 & ~0x04, addr+2); // send init
+ udelay(5);
+ outb(val8 | 0x04, addr+2);
+
+ regs->ah = inb(addr+1) ^ 0x48;
+ set_success(regs);
+}
+
+// INT 17 - PRINTER - GET STATUS
+static void
+handle_1702(struct bregs *regs)
+{
+ u16 addr = getLptAddr(regs);
+ if (!addr)
+ return;
+ regs->ah = inb(addr+1) ^ 0x48;
+ set_success(regs);
+}
+
+static void
+handle_17XX(struct bregs *regs)
+{
+ set_unimplemented(regs);
+}
+
+// INT17h : Printer Service Entry Point
+void VISIBLE16
+handle_17(struct bregs *regs)
+{
+ debug_enter(regs, DEBUG_HDL_17);
+ if (! CONFIG_LPT) {
+ handle_17XX(regs);
+ return;
+ }
+
+ switch (regs->ah) {
+ case 0x00: handle_1700(regs); break;
+ case 0x01: handle_1701(regs); break;
+ case 0x02: handle_1702(regs); break;
+ default: handle_17XX(regs); break;
+ }
+}
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