From 5427bcf5e95245d3e220742ac703182bdb973769 Mon Sep 17 00:00:00 2001 From: Mike Frysinger Date: Fri, 4 Feb 2011 20:45:49 -0500 Subject: hvc: add Blackfin JTAG console support This converts the existing bfin_jtag_comm TTY driver to the HVC layer so that the common HVC code can worry about all of the TTY/polling crap and leave the Blackfin code to worry about the Blackfin bits. Signed-off-by: Mike Frysinger Signed-off-by: Greg Kroah-Hartman --- drivers/tty/hvc/Makefile | 1 + drivers/tty/hvc/hvc_bfin_jtag.c | 105 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 106 insertions(+) create mode 100644 drivers/tty/hvc/hvc_bfin_jtag.c (limited to 'drivers/tty/hvc') diff --git a/drivers/tty/hvc/Makefile b/drivers/tty/hvc/Makefile index e6bed5f177ff..7b0edbce9009 100644 --- a/drivers/tty/hvc/Makefile +++ b/drivers/tty/hvc/Makefile @@ -9,5 +9,6 @@ obj-$(CONFIG_HVC_IRQ) += hvc_irq.o obj-$(CONFIG_HVC_XEN) += hvc_xen.o obj-$(CONFIG_HVC_IUCV) += hvc_iucv.o obj-$(CONFIG_HVC_UDBG) += hvc_udbg.o +obj-$(CONFIG_HVC_BFIN_JTAG) += hvc_bfin_jtag.o obj-$(CONFIG_HVCS) += hvcs.o obj-$(CONFIG_VIRTIO_CONSOLE) += virtio_console.o diff --git a/drivers/tty/hvc/hvc_bfin_jtag.c b/drivers/tty/hvc/hvc_bfin_jtag.c new file mode 100644 index 000000000000..31d6cc6a77af --- /dev/null +++ b/drivers/tty/hvc/hvc_bfin_jtag.c @@ -0,0 +1,105 @@ +/* + * Console via Blackfin JTAG Communication + * + * Copyright 2008-2011 Analog Devices Inc. + * + * Enter bugs at http://blackfin.uclinux.org/ + * + * Licensed under the GPL-2 or later. + */ + +#include +#include +#include +#include +#include +#include + +#include "hvc_console.h" + +/* See the Debug/Emulation chapter in the HRM */ +#define EMUDOF 0x00000001 /* EMUDAT_OUT full & valid */ +#define EMUDIF 0x00000002 /* EMUDAT_IN full & valid */ +#define EMUDOOVF 0x00000004 /* EMUDAT_OUT overflow */ +#define EMUDIOVF 0x00000008 /* EMUDAT_IN overflow */ + +/* Helper functions to glue the register API to simple C operations */ +static inline uint32_t bfin_write_emudat(uint32_t emudat) +{ + __asm__ __volatile__("emudat = %0;" : : "d"(emudat)); + return emudat; +} + +static inline uint32_t bfin_read_emudat(void) +{ + uint32_t emudat; + __asm__ __volatile__("%0 = emudat;" : "=d"(emudat)); + return emudat; +} + +/* Send data to the host */ +static int hvc_bfin_put_chars(uint32_t vt, const char *buf, int count) +{ + static uint32_t outbound_len; + uint32_t emudat; + int ret; + + if (bfin_read_DBGSTAT() & EMUDOF) + return 0; + + if (!outbound_len) { + outbound_len = count; + bfin_write_emudat(outbound_len); + return 0; + } + + ret = min(outbound_len, (uint32_t)4); + memcpy(&emudat, buf, ret); + bfin_write_emudat(emudat); + outbound_len -= ret; + + return ret; +} + +/* Receive data from the host */ +static int hvc_bfin_get_chars(uint32_t vt, char *buf, int count) +{ + static uint32_t inbound_len; + uint32_t emudat; + int ret; + + if (!(bfin_read_DBGSTAT() & EMUDIF)) + return 0; + emudat = bfin_read_emudat(); + + if (!inbound_len) { + inbound_len = emudat; + return 0; + } + + ret = min(inbound_len, (uint32_t)4); + memcpy(buf, &emudat, ret); + inbound_len -= ret; + + return ret; +} + +/* Glue the HVC layers to the Blackfin layers */ +static const struct hv_ops hvc_bfin_get_put_ops = { + .get_chars = hvc_bfin_get_chars, + .put_chars = hvc_bfin_put_chars, +}; + +static int __init hvc_bfin_console_init(void) +{ + hvc_instantiate(0, 0, &hvc_bfin_get_put_ops); + return 0; +} +console_initcall(hvc_bfin_console_init); + +static int __init hvc_bfin_init(void) +{ + hvc_alloc(0, 0, &hvc_bfin_get_put_ops, 128); + return 0; +} +device_initcall(hvc_bfin_init); -- cgit v1.2.3