From 9dae8afdf212d39bc7c25f1b1ca9b10f10f6beaa Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Fri, 21 Dec 2007 15:39:26 +1100 Subject: [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 Signed-off-by: Josh Boyer --- arch/powerpc/kernel/udbg_16550.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'arch/powerpc/kernel/udbg_16550.c') diff --git a/arch/powerpc/kernel/udbg_16550.c b/arch/powerpc/kernel/udbg_16550.c index df740eae77b..cb01ebc5938 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 */ -- cgit v1.2.3