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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/mips/boot/compressed/uart-16550.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/mips/boot/compressed/uart-16550.c')
-rw-r--r--arch/mips/boot/compressed/uart-16550.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/mips/boot/compressed/uart-16550.c b/arch/mips/boot/compressed/uart-16550.c
new file mode 100644
index 000000000..aee8d7b8f
--- /dev/null
+++ b/arch/mips/boot/compressed/uart-16550.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 16550 compatible uart based serial debug support for zboot
+ */
+
+#include <linux/types.h>
+#include <linux/serial_reg.h>
+
+#include <asm/addrspace.h>
+
+#if defined(CONFIG_MACH_LOONGSON64) || defined(CONFIG_MIPS_MALTA)
+#define UART_BASE 0x1fd003f8
+#define PORT(offset) (CKSEG1ADDR(UART_BASE) + (offset))
+#endif
+
+#ifdef CONFIG_AR7
+#include <ar7.h>
+#define PORT(offset) (CKSEG1ADDR(AR7_REGS_UART0) + (4 * offset))
+#endif
+
+#ifdef CONFIG_MACH_INGENIC
+#define INGENIC_UART0_BASE_ADDR 0x10030000
+#define PORT(offset) (CKSEG1ADDR(INGENIC_UART0_BASE_ADDR) + (4 * offset))
+#endif
+
+#ifdef CONFIG_CPU_XLR
+#define UART0_BASE 0x1EF14000
+#define PORT(offset) (CKSEG1ADDR(UART0_BASE) + (4 * offset))
+#define IOTYPE unsigned int
+#endif
+
+#ifdef CONFIG_CPU_XLP
+#define UART0_BASE 0x18030100
+#define PORT(offset) (CKSEG1ADDR(UART0_BASE) + (4 * offset))
+#define IOTYPE unsigned int
+#endif
+
+#ifndef IOTYPE
+#define IOTYPE char
+#endif
+
+#ifndef PORT
+#error please define the serial port address for your own machine
+#endif
+
+static inline unsigned int serial_in(int offset)
+{
+ return *((volatile IOTYPE *)PORT(offset)) & 0xFF;
+}
+
+static inline void serial_out(int offset, int value)
+{
+ *((volatile IOTYPE *)PORT(offset)) = value & 0xFF;
+}
+
+void putc(char c)
+{
+ int timeout = 1000000;
+
+ while (((serial_in(UART_LSR) & UART_LSR_THRE) == 0) && (timeout-- > 0))
+ ;
+
+ serial_out(UART_TX, c);
+}