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Diffstat (limited to 'target/linux/brcm47xx/patches-3.10/080-MIPS-Add-8250-16550-serial-early-printk-driver.patch')
-rw-r--r--target/linux/brcm47xx/patches-3.10/080-MIPS-Add-8250-16550-serial-early-printk-driver.patch124
1 files changed, 124 insertions, 0 deletions
diff --git a/target/linux/brcm47xx/patches-3.10/080-MIPS-Add-8250-16550-serial-early-printk-driver.patch b/target/linux/brcm47xx/patches-3.10/080-MIPS-Add-8250-16550-serial-early-printk-driver.patch
new file mode 100644
index 0000000000..bfbe43be5b
--- /dev/null
+++ b/target/linux/brcm47xx/patches-3.10/080-MIPS-Add-8250-16550-serial-early-printk-driver.patch
@@ -0,0 +1,124 @@
+commit 0a76092a63809a0e72e3e9552acadf42869c0293
+Author: Yoichi Yuasa <yuasa@linux-mips.org>
+Date: Mon Feb 8 20:59:39 2010 +0900
+
+ MIPS: Add 8250/16550 serial early printk driver
+
+ Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
+ Cc: linux-mips <linux-mips@linux-mips.org>
+ Patchwork: https://patchwork.linux-mips.org/patch/947/
+ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
+
+--- a/arch/mips/Kconfig.debug
++++ b/arch/mips/Kconfig.debug
+@@ -20,6 +20,14 @@ config EARLY_PRINTK
+ doesn't cooperate with an X server. You should normally say N here,
+ unless you want to debug such a crash.
+
++config EARLY_PRINTK_8250
++ bool "8250/16550 and compatible serial early printk driver"
++ depends on EARLY_PRINTK
++ default n
++ help
++ If you say Y here, it will be possible to use a 8250/16550 serial
++ port as the boot console.
++
+ config CMDLINE_BOOL
+ bool "Built-in kernel command line"
+ default n
+--- a/arch/mips/include/asm/setup.h
++++ b/arch/mips/include/asm/setup.h
+@@ -5,6 +5,14 @@
+
+ extern void setup_early_printk(void);
+
++#ifdef CONFIG_EARLY_PRINTK_8250
++extern void setup_8250_early_printk_port(unsigned long base,
++ unsigned int reg_shift, unsigned int timeout);
++#else
++static inline void setup_8250_early_printk_port(unsigned long base,
++ unsigned int reg_shift, unsigned int timeout) {}
++#endif
++
+ extern void set_handler(unsigned long offset, void *addr, unsigned long len);
+ extern void set_uncached_handler(unsigned long offset, void *addr, unsigned long len);
+
+--- a/arch/mips/kernel/Makefile
++++ b/arch/mips/kernel/Makefile
+@@ -84,6 +84,7 @@ obj-$(CONFIG_GPIO_TXX9) += gpio_txx9.o
+ obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o crash.o
+ obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
+ obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
++obj-$(CONFIG_EARLY_PRINTK_8250) += early_printk_8250.o
+ obj-$(CONFIG_SPINLOCK_TEST) += spinlock_test.o
+ obj-$(CONFIG_MIPS_MACHINE) += mips_machine.o
+
+--- /dev/null
++++ b/arch/mips/kernel/early_printk_8250.c
+@@ -0,0 +1,66 @@
++/*
++ * 8250/16550-type serial ports prom_putchar()
++ *
++ * Copyright (C) 2010 Yoichi Yuasa <yuasa@linux-mips.org>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License as published by
++ * the Free Software Foundation; either version 2 of the License, or
++ * (at your option) any later version.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public License
++ * along with this program; if not, write to the Free Software
++ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
++ */
++#include <linux/io.h>
++#include <linux/serial_core.h>
++#include <linux/serial_reg.h>
++
++static void __iomem *serial8250_base;
++static unsigned int serial8250_reg_shift;
++static unsigned int serial8250_tx_timeout;
++
++void setup_8250_early_printk_port(unsigned long base, unsigned int reg_shift,
++ unsigned int timeout)
++{
++ serial8250_base = (void __iomem *)base;
++ serial8250_reg_shift = reg_shift;
++ serial8250_tx_timeout = timeout;
++}
++
++static inline u8 serial_in(int offset)
++{
++ return readb(serial8250_base + (offset << serial8250_reg_shift));
++}
++
++static inline void serial_out(int offset, char value)
++{
++ writeb(value, serial8250_base + (offset << serial8250_reg_shift));
++}
++
++void prom_putchar(char c)
++{
++ unsigned int timeout;
++ int status, bits;
++
++ if (!serial8250_base)
++ return;
++
++ timeout = serial8250_tx_timeout;
++ bits = UART_LSR_TEMT | UART_LSR_THRE;
++
++ do {
++ status = serial_in(UART_LSR);
++
++ if (--timeout == 0)
++ break;
++ } while ((status & bits) != bits);
++
++ if (timeout)
++ serial_out(UART_TX, c);
++}