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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 02:56:35 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 02:56:35 +0000
commiteba0cfa6b0bef4f2e73c8630a7efa3944df8b0f8 (patch)
tree74c37eede1f0634cc5de1c63c934edaa1630c6bc /purgatory/arch/i386/console-x86.c
parentInitial commit. (diff)
downloadkexec-tools-eba0cfa6b0bef4f2e73c8630a7efa3944df8b0f8.tar.xz
kexec-tools-eba0cfa6b0bef4f2e73c8630a7efa3944df8b0f8.zip
Adding upstream version 1:2.0.27.upstream/1%2.0.27upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'purgatory/arch/i386/console-x86.c')
-rw-r--r--purgatory/arch/i386/console-x86.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/purgatory/arch/i386/console-x86.c b/purgatory/arch/i386/console-x86.c
new file mode 100644
index 0000000..9773573
--- /dev/null
+++ b/purgatory/arch/i386/console-x86.c
@@ -0,0 +1,135 @@
+#include <stdint.h>
+#include <arch/io.h>
+#include <purgatory.h>
+
+/*
+ * VGA
+ * =============================================================================
+ */
+
+/* Simple VGA output */
+
+#define VGABASE ((void *)0xb8000)
+
+#define MAX_YPOS 25
+#define MAX_XPOS 80
+
+static int current_ypos = 1, current_xpos = 0;
+uint8_t console_vga = 0;
+
+static void putchar_vga(int ch)
+{
+ int i, k, j;
+ if (!console_vga)
+ return;
+
+ if (current_ypos >= MAX_YPOS) {
+ /* scroll 1 line up */
+ for (k = 1, j = 0; k < MAX_YPOS; k++, j++) {
+ for (i = 0; i < MAX_XPOS; i++) {
+ writew(readw(VGABASE + 2*(MAX_XPOS*k + i)),
+ VGABASE + 2*(MAX_XPOS*j + i));
+ }
+ }
+ for (i = 0; i < MAX_XPOS; i++)
+ writew(0x720, VGABASE + 2*(MAX_XPOS*j + i));
+ current_ypos = MAX_YPOS-1;
+ }
+ if (ch == '\n') {
+ current_xpos = 0;
+ current_ypos++;
+ } else if (ch != '\r') {
+ writew(((0x7 << 8) | (unsigned short) ch),
+ VGABASE + 2*(MAX_XPOS*current_ypos +
+ current_xpos++));
+ if (current_xpos >= MAX_XPOS) {
+ current_xpos = 0;
+ current_ypos++;
+ }
+ }
+}
+
+/*
+ * Serial
+ * =============================================================================
+ */
+
+/* Base Address */
+uint8_t console_serial = 0;
+uint16_t serial_base = 0x3f8; /* TTYS0 */
+uint32_t serial_baud = 0;
+
+#define XMTRDY 0x20
+
+#define DLAB 0x80
+
+#define TXR 0 /* Transmit register (WRITE) */
+#define TBR 0 /* Transmit register (WRITE) */
+#define RXR 0 /* Receive register (READ) */
+#define IER 1 /* Interrupt Enable */
+#define IIR 2 /* Interrupt ID */
+#define FCR 2 /* FIFO control */
+#define LCR 3 /* Line control */
+#define MCR 4 /* Modem control */
+#define LSR 5 /* Line Status */
+#define MSR 6 /* Modem Status */
+#define DLL 0 /* Divisor Latch Low */
+#define DLH 1 /* Divisor latch High */
+
+static void serial_init(void)
+{
+ static int initialized = 0;
+ if (!initialized) {
+ unsigned lcr;
+ outb(0x3, serial_base + LCR); /* 8n1 */
+ outb(0, serial_base + IER); /* no interrupt */
+ outb(0, serial_base + FCR); /* no fifo */
+ outb(0x3, serial_base + MCR); /* DTR + RTS */
+
+ lcr = inb(serial_base + LCR);
+ outb(lcr | DLAB, serial_base + LCR);
+ /* By default don't change the serial port baud rate */
+ if (serial_baud) {
+ unsigned divisor = 115200 / serial_baud;
+ outb(divisor & 0xff, serial_base + DLL);
+ outb((divisor >> 8) & 0xff, serial_base + DLH);
+ }
+ outb(lcr & ~DLAB, serial_base + LCR);
+ initialized = 1;
+ }
+}
+
+static void serial_tx_byte(unsigned byte)
+{
+ /* Ensure the serial port is initialized */
+ serial_init();
+
+ /* Wait until I can send a byte */
+ while((inb(serial_base + LSR) & 0x20) == 0)
+ ;
+ outb(byte, serial_base + TBR);
+ /* Wait until the byte is transmitted */
+ while(!(inb(serial_base + LSR) & 0x40))
+ ;
+}
+
+static void putchar_serial(int ch)
+{
+ if (!console_serial) {
+ return;
+ }
+ if (ch == '\n') {
+ serial_tx_byte('\r');
+ }
+ serial_tx_byte(ch);
+}
+
+/* Generic wrapper function */
+
+void putchar(int ch)
+{
+ putchar_vga(ch);
+ putchar_serial(ch);
+}
+
+