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-rw-r--r--arch/powerpc/Kconfig.debug15
-rw-r--r--arch/powerpc/include/asm/udbg.h1
-rw-r--r--arch/powerpc/kernel/udbg.c2
-rw-r--r--arch/powerpc/kernel/udbg_16550.c33
4 files changed, 51 insertions, 0 deletions
diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug
index ae727d4218b9..6aaf8dc60610 100644
--- a/arch/powerpc/Kconfig.debug
+++ b/arch/powerpc/Kconfig.debug
@@ -283,6 +283,12 @@ config PPC_EARLY_DEBUG_MEMCONS
This console provides input and output buffers stored within the
kernel BSS and should be safe to select on any system. A debugger
can then be used to read kernel output or send input to the console.
+
+config PPC_EARLY_DEBUG_16550
+ bool "Serial 16550"
+ depends on PPC_UDBG_16550
+ help
+ Select this to enable early debugging via Serial 16550 console
endchoice
config PPC_MEMCONS_OUTPUT_SIZE
@@ -354,6 +360,15 @@ config PPC_EARLY_DEBUG_CPM_ADDR
platform probing is done, all platforms selected must
share the same address.
+config PPC_EARLY_DEBUG_16550_PHYSADDR
+ hex "Early debug Serial 16550 physical address"
+ depends on PPC_EARLY_DEBUG_16550
+
+config PPC_EARLY_DEBUG_16550_STRIDE
+ int "Early debug Serial 16550 stride"
+ depends on PPC_EARLY_DEBUG_16550
+ default 1
+
config FAIL_IOMMU
bool "Fault-injection capability for IOMMU"
depends on FAULT_INJECTION
diff --git a/arch/powerpc/include/asm/udbg.h b/arch/powerpc/include/asm/udbg.h
index 524c2085070f..88add5593e6f 100644
--- a/arch/powerpc/include/asm/udbg.h
+++ b/arch/powerpc/include/asm/udbg.h
@@ -52,6 +52,7 @@ extern void __init udbg_init_ehv_bc(void);
extern void __init udbg_init_ps3gelic(void);
extern void __init udbg_init_debug_opal_raw(void);
extern void __init udbg_init_debug_opal_hvsi(void);
+extern void __init udbg_init_debug_16550(void);
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_UDBG_H */
diff --git a/arch/powerpc/kernel/udbg.c b/arch/powerpc/kernel/udbg.c
index b1544b2f6321..92b3fc258d11 100644
--- a/arch/powerpc/kernel/udbg.c
+++ b/arch/powerpc/kernel/udbg.c
@@ -67,6 +67,8 @@ void __init udbg_early_init(void)
udbg_init_debug_opal_raw();
#elif defined(CONFIG_PPC_EARLY_DEBUG_OPAL_HVSI)
udbg_init_debug_opal_hvsi();
+#elif defined(CONFIG_PPC_EARLY_DEBUG_16550)
+ udbg_init_debug_16550();
#endif
#ifdef CONFIG_PPC_EARLY_DEBUG
diff --git a/arch/powerpc/kernel/udbg_16550.c b/arch/powerpc/kernel/udbg_16550.c
index ddfbc74bf85f..74ddf836f7a2 100644
--- a/arch/powerpc/kernel/udbg_16550.c
+++ b/arch/powerpc/kernel/udbg_16550.c
@@ -8,6 +8,7 @@
#include <asm/udbg.h>
#include <asm/io.h>
#include <asm/reg_a2.h>
+#include <asm/early_ioremap.h>
extern u8 real_readb(volatile u8 __iomem *addr);
extern void real_writeb(u8 data, volatile u8 __iomem *addr);
@@ -296,3 +297,35 @@ void __init udbg_init_40x_realmode(void)
}
#endif /* CONFIG_PPC_EARLY_DEBUG_40x */
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_16550
+
+static void __iomem *udbg_uart_early_addr;
+
+void __init udbg_init_debug_16550(void)
+{
+ udbg_uart_early_addr = early_ioremap(CONFIG_PPC_EARLY_DEBUG_16550_PHYSADDR, 0x1000);
+ udbg_uart_init_mmio(udbg_uart_early_addr, CONFIG_PPC_EARLY_DEBUG_16550_STRIDE);
+}
+
+static int __init udbg_init_debug_16550_ioremap(void)
+{
+ void __iomem *addr;
+
+ if (!udbg_uart_early_addr)
+ return 0;
+
+ addr = ioremap(CONFIG_PPC_EARLY_DEBUG_16550_PHYSADDR, 0x1000);
+ if (WARN_ON(!addr))
+ return -ENOMEM;
+
+ udbg_uart_init_mmio(addr, CONFIG_PPC_EARLY_DEBUG_16550_STRIDE);
+ early_iounmap(udbg_uart_early_addr, 0x1000);
+ udbg_uart_early_addr = NULL;
+
+ return 0;
+}
+
+early_initcall(udbg_init_debug_16550_ioremap);
+
+#endif /* CONFIG_PPC_EARLY_DEBUG_16550 */