From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Cc: linuxppc-dev@ozlabs.org
Subject: [PATCH 7/20] [POWERPC] Add early udbg support for 40x processors
Date: Thu, 13 Dec 2007 18:38:35 +1100 [thread overview]
Message-ID: <20071213073841.156B8DDFC5@ozlabs.org> (raw)
This adds some basic real mode based early udbg support for 40x
in order to debug things more easily
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
arch/powerpc/Kconfig.debug | 13 +++++++++++
arch/powerpc/kernel/misc_32.S | 39 +++++++++++++++++++++++++++++++++
arch/powerpc/kernel/udbg.c | 3 ++
arch/powerpc/kernel/udbg_16550.c | 33 +++++++++++++++++++++++++++
arch/powerpc/platforms/Kconfig.cputype | 1
include/asm-powerpc/udbg.h | 1
6 files changed, 90 insertions(+)
--- linux-merge.orig/arch/powerpc/Kconfig.debug 2007-12-11 16:30:53.000000000 +1100
+++ linux-merge/arch/powerpc/Kconfig.debug 2007-12-11 16:33:16.000000000 +1100
@@ -227,6 +227,14 @@ config PPC_EARLY_DEBUG_44x
Select this to enable early debugging for IBM 44x chips via the
inbuilt serial port.
+config PPC_EARLY_DEBUG_40x
+ bool "Early serial debugging for IBM/AMCC 40x CPUs"
+ depends on 40x
+ help
+ Select this to enable early debugging for IBM 40x chips via the
+ inbuilt serial port. This works on chips with a 16550 compatible
+ UART. Xilinx chips with uartlite cannot use this option.
+
config PPC_EARLY_DEBUG_CPM
bool "Early serial debugging for Freescale CPM-based serial ports"
depends on SERIAL_CPM
@@ -248,6 +256,11 @@ config PPC_EARLY_DEBUG_44x_PHYSHIGH
depends on PPC_EARLY_DEBUG_44x
default "0x1"
+config PPC_EARLY_DEBUG_40x_PHYSADDR
+ hex "Early debug UART physical address"
+ depends on PPC_EARLY_DEBUG_40x
+ default "0xef600300"
+
config PPC_EARLY_DEBUG_CPM_ADDR
hex "CPM UART early debug transmit descriptor address"
depends on PPC_EARLY_DEBUG_CPM
Index: linux-merge/arch/powerpc/kernel/misc_32.S
===================================================================
--- linux-merge.orig/arch/powerpc/kernel/misc_32.S 2007-12-11 15:07:22.000000000 +1100
+++ linux-merge/arch/powerpc/kernel/misc_32.S 2007-12-11 16:33:16.000000000 +1100
@@ -206,6 +206,45 @@ _GLOBAL(_nmask_and_or_msr)
isync
blr /* Done */
+#ifdef CONFIG_40x
+
+/*
+ * Do an IO access in real mode
+ */
+_GLOBAL(real_readb)
+ mfmsr r7
+ ori r0,r7,MSR_DR
+ xori r0,r0,MSR_DR
+ sync
+ mtmsr r0
+ sync
+ isync
+ lbz r3,0(r3)
+ sync
+ mtmsr r7
+ sync
+ isync
+ blr
+
+ /*
+ * Do an IO access in real mode
+ */
+_GLOBAL(real_writeb)
+ mfmsr r7
+ ori r0,r7,MSR_DR
+ xori r0,r0,MSR_DR
+ sync
+ mtmsr r0
+ sync
+ isync
+ stb r3,0(r4)
+ sync
+ mtmsr r7
+ sync
+ isync
+ blr
+
+#endif /* CONFIG_40x */
/*
* Flush MMU TLB
Index: linux-merge/arch/powerpc/kernel/udbg.c
===================================================================
--- linux-merge.orig/arch/powerpc/kernel/udbg.c 2007-12-11 16:30:53.000000000 +1100
+++ linux-merge/arch/powerpc/kernel/udbg.c 2007-12-11 16:33:16.000000000 +1100
@@ -54,6 +54,9 @@ void __init udbg_early_init(void)
#elif defined(CONFIG_PPC_EARLY_DEBUG_44x)
/* PPC44x debug */
udbg_init_44x_as1();
+#elif defined(CONFIG_PPC_EARLY_DEBUG_40x)
+ /* PPC40x debug */
+ udbg_init_40x_realmode();
#elif defined(CONFIG_PPC_EARLY_DEBUG_CPM)
udbg_init_cpm();
#endif
Index: linux-merge/arch/powerpc/kernel/udbg_16550.c
===================================================================
--- linux-merge.orig/arch/powerpc/kernel/udbg_16550.c 2007-12-11 16:30:53.000000000 +1100
+++ linux-merge/arch/powerpc/kernel/udbg_16550.c 2007-12-11 16:33:16.000000000 +1100
@@ -225,3 +225,36 @@ void __init udbg_init_44x_as1(void)
udbg_getc = udbg_44x_as1_getc;
}
#endif /* CONFIG_PPC_EARLY_DEBUG_44x */
+
+#ifdef CONFIG_PPC_EARLY_DEBUG_40x
+static void udbg_40x_real_putc(char c)
+{
+ if (udbg_comport) {
+ while ((real_readb(&udbg_comport->lsr) & LSR_THRE) == 0)
+ /* wait for idle */;
+ real_writeb(c, &udbg_comport->thr); eieio();
+ if (c == '\n')
+ udbg_40x_real_putc('\r');
+ }
+}
+
+static int udbg_40x_real_getc(void)
+{
+ if (udbg_comport) {
+ while ((real_readb(&udbg_comport->lsr) & LSR_DR) == 0)
+ ; /* wait for char */
+ return real_readb(&udbg_comport->rbr);
+ }
+ return -1;
+}
+
+void __init udbg_init_40x_realmode(void)
+{
+ udbg_comport = (struct NS16550 __iomem *)
+ CONFIG_PPC_EARLY_DEBUG_40x_PHYSADDR;
+
+ udbg_putc = udbg_40x_real_putc;
+ udbg_getc = udbg_40x_real_getc;
+ udbg_getc_poll = NULL;
+}
+#endif /* CONFIG_PPC_EARLY_DEBUG_40x */
Index: linux-merge/include/asm-powerpc/udbg.h
===================================================================
--- linux-merge.orig/include/asm-powerpc/udbg.h 2007-10-15 11:19:39.000000000 +1000
+++ linux-merge/include/asm-powerpc/udbg.h 2007-12-11 16:33:16.000000000 +1100
@@ -48,6 +48,7 @@ extern void __init udbg_init_rtas_consol
extern void __init udbg_init_debug_beat(void);
extern void __init udbg_init_btext(void);
extern void __init udbg_init_44x_as1(void);
+extern void __init udbg_init_40x_realmode(void);
extern void __init udbg_init_cpm(void);
#endif /* __KERNEL__ */
Index: linux-merge/arch/powerpc/platforms/Kconfig.cputype
===================================================================
--- linux-merge.orig/arch/powerpc/platforms/Kconfig.cputype 2007-10-25 13:15:47.000000000 +1000
+++ linux-merge/arch/powerpc/platforms/Kconfig.cputype 2007-12-11 16:33:16.000000000 +1100
@@ -43,6 +43,7 @@ config 40x
bool "AMCC 40x"
select PPC_DCR_NATIVE
select WANT_DEVICE_TREE
+ select PPC_UDBG_16550
config 44x
bool "AMCC 44x"
reply other threads:[~2007-12-13 7:38 UTC|newest]
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