xen: use the hvc console infrastructure for Xen console (b536b4b9) · Commits · e / devices / android_kernel_fairphone_FP4

arch/i386/xen/events.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -244,7 +244,7 @@ static int find_unbound_irq(void)
		return irq;
		}

		static int bind_evtchn_to_irq(unsigned int evtchn)
		int bind_evtchn_to_irq(unsigned int evtchn)
		{
		int irq;

		@@ -269,6 +269,7 @@ static int bind_evtchn_to_irq(unsigned int evtchn)

		return irq;
		}
		EXPORT_SYMBOL_GPL(bind_evtchn_to_irq);

		static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
		{

arch/x86_64/kernel/early_printk.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -6,6 +6,7 @@
		#include <asm/io.h>
		#include <asm/processor.h>
		#include <asm/fcntl.h>
		#include <xen/hvc-console.h>

		/* Simple VGA output */

		@@ -242,6 +243,10 @@ static int __init setup_early_printk(char *buf)
		simnow_init(buf + 6);
		early_console = &simnow_console;
		keep_early = 1;
		#ifdef CONFIG_HVC_XEN
		} else if (!strncmp(buf, "xen", 3)) {
		early_console = &xenboot_console;
		#endif
		}

		if (keep_early)

drivers/char/Kconfig

+8 −0

Original line number	Diff line number	Diff line
		@@ -604,6 +604,14 @@ config HVC_BEAT
		help
		Toshiba's Cell Reference Set Beat Console device driver

		config HVC_XEN
		bool "Xen Hypervisor Console support"
		depends on XEN
		select HVC_DRIVER
		default y
		help
		Xen virtual console device driver

		config HVCS
		tristate "IBM Hypervisor Virtual Console Server support"
		depends on PPC_PSERIES

drivers/char/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -48,6 +48,7 @@ obj-$(CONFIG_HVC_ISERIES) += hvc_iseries.o
		obj-$(CONFIG_HVC_RTAS) += hvc_rtas.o
		obj-$(CONFIG_HVC_BEAT) += hvc_beat.o
		obj-$(CONFIG_HVC_DRIVER) += hvc_console.o
		obj-$(CONFIG_HVC_XEN) += hvc_xen.o
		obj-$(CONFIG_RAW_DRIVER) += raw.o
		obj-$(CONFIG_SGI_SNSC) += snsc.o snsc_event.o
		obj-$(CONFIG_MSPEC) += mspec.o

drivers/char/hvc_xen.c

0 → 100644

+159 −0

Original line number	Diff line number	Diff line
		/*
		* xen console driver interface to hvc_console.c
		*
		* (c) 2007 Gerd Hoffmann <kraxel@suse.de>
		*
		* This program is free software; you can redistribute it and/or modify
		* it under the terms of the GNU General Public License as published by
		* the Free Software Foundation; either version 2 of the License, or
		* (at your option) any later version.
		*
		* This program is distributed in the hope that it will be useful,
		* but WITHOUT ANY WARRANTY; without even the implied warranty of
		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
		* GNU General Public License for more details.
		*
		* You should have received a copy of the GNU General Public License
		* along with this program; if not, write to the Free Software
		* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
		*/

		#include <linux/console.h>
		#include <linux/delay.h>
		#include <linux/err.h>
		#include <linux/init.h>
		#include <linux/types.h>

		#include <asm/xen/hypervisor.h>
		#include <xen/page.h>
		#include <xen/events.h>
		#include <xen/interface/io/console.h>
		#include <xen/hvc-console.h>

		#include "hvc_console.h"

		#define HVC_COOKIE 0x58656e /* "Xen" in hex */

		static struct hvc_struct *hvc;
		static int xencons_irq;

		/* ------------------------------------------------------------------ */

		static inline struct xencons_interface *xencons_interface(void)
		{
		return mfn_to_virt(xen_start_info->console.domU.mfn);
		}

		static inline void notify_daemon(void)
		{
		/* Use evtchn: this is called early, before irq is set up. */
		notify_remote_via_evtchn(xen_start_info->console.domU.evtchn);
		}

		static int write_console(uint32_t vtermno, const char *data, int len)
		{
		struct xencons_interface *intf = xencons_interface();
		XENCONS_RING_IDX cons, prod;
		int sent = 0;

		cons = intf->out_cons;
		prod = intf->out_prod;
		mb(); /* update queue values before going on */
		BUG_ON((prod - cons) > sizeof(intf->out));

		while ((sent < len) && ((prod - cons) < sizeof(intf->out)))
		intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++];

		wmb(); /* write ring before updating pointer */
		intf->out_prod = prod;

		notify_daemon();
		return sent;
		}

		static int read_console(uint32_t vtermno, char *buf, int len)
		{
		struct xencons_interface *intf = xencons_interface();
		XENCONS_RING_IDX cons, prod;
		int recv = 0;

		cons = intf->in_cons;
		prod = intf->in_prod;
		mb(); /* get pointers before reading ring */
		BUG_ON((prod - cons) > sizeof(intf->in));

		while (cons != prod && recv < len)
		buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)];

		mb(); /* read ring before consuming */
		intf->in_cons = cons;

		notify_daemon();
		return recv;
		}

		static struct hv_ops hvc_ops = {
		.get_chars = read_console,
		.put_chars = write_console,
		};

		static int __init xen_init(void)
		{
		struct hvc_struct *hp;

		if (!is_running_on_xen())
		return 0;

		xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn);
		if (xencons_irq < 0)
		xencons_irq = 0 /* NO_IRQ */;
		hp = hvc_alloc(HVC_COOKIE, xencons_irq, &hvc_ops, 256);
		if (IS_ERR(hp))
		return PTR_ERR(hp);

		hvc = hp;
		return 0;
		}

		static void __exit xen_fini(void)
		{
		if (hvc)
		hvc_remove(hvc);
		}

		static int xen_cons_init(void)
		{
		if (!is_running_on_xen())
		return 0;

		hvc_instantiate(HVC_COOKIE, 0, &hvc_ops);
		return 0;
		}

		module_init(xen_init);
		module_exit(xen_fini);
		console_initcall(xen_cons_init);

		static void xenboot_write_console(struct console console, const char string,
		unsigned len)
		{
		unsigned int linelen, off = 0;
		const char *pos;

		while (off < len && NULL != (pos = strchr(string+off, '\n'))) {
		linelen = pos-string+off;
		if (off + linelen > len)
		break;
		write_console(0, string+off, linelen);
		write_console(0, "\r\n", 2);
		off += linelen + 1;
		}
		if (off < len)
		write_console(0, string+off, len-off);
		}

		struct console xenboot_console = {
		.name = "xenboot",
		.write = xenboot_write_console,
		.flags = CON_PRINTBUFFER \| CON_BOOT,
		};