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| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2007-12-21 15:39:26 +1100 |
|---|---|---|
| committer | Josh Boyer <jwboyer@linux.vnet.ibm.com> | 2007-12-23 13:13:03 -0600 |
| commit | 9dae8afdf212d39bc7c25f1b1ca9b10f10f6beaa (patch) | |
| tree | 12721945adf3a3fc01ba292e1756af4826a7eed3 /arch/powerpc/kernel/udbg_16550.c | |
| parent | 69c0785112921a43739495a68f459fde88a9bbd8 (diff) | |
| download | lwn-9dae8afdf212d39bc7c25f1b1ca9b10f10f6beaa.tar.gz lwn-9dae8afdf212d39bc7c25f1b1ca9b10f10f6beaa.zip | |
[POWERPC] 4xx: Add early udbg support for 40x processors
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>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Diffstat (limited to 'arch/powerpc/kernel/udbg_16550.c')
| -rw-r--r-- | arch/powerpc/kernel/udbg_16550.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/udbg_16550.c b/arch/powerpc/kernel/udbg_16550.c index df740eae77b8..cb01ebc59387 100644 --- a/arch/powerpc/kernel/udbg_16550.c +++ b/arch/powerpc/kernel/udbg_16550.c @@ -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 */ |