embox

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/**
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 * @file
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 * @brief
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 *
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 * @date 17.03.2012
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 * @author Andrey Golikov
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 * @author Anton Kozlov
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 */
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#include <drivers/diag.h>
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#include <stdint.h>
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#include <xen/xen.h>
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#include <xen/io/console.h>
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#include <xen_hypercall-x86_32.h>
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#include <barrier.h>
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#include <assert.h>
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static evtchn_port_t console_evt;
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extern char _text_vma;
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struct xencons_interface * console;
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static int diag_xen_init(const struct diag *diag) {
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	extern start_info_t *xen_start_info_global;
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	console = (struct xencons_interface*)
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		((machine_to_phys_mapping[xen_start_info_global->console.domU.mfn] << 12)
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		 +
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		((unsigned long)&_text_vma));
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	console_evt = xen_start_info_global->console.domU.evtchn;
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	/* TODO: Set up the event channel */
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	return 0;
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}
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static void diag_xen_putc(const struct diag *diag, char ch) {
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	struct evtchn_send event;
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	event.port = console_evt;
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	char message[1];
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	message[0] = ch;
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	{
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		/* Wait for the back end to clear enough space in the buffer */
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		XENCONS_RING_IDX data;
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		do
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		{
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			data = console->out_prod - console->out_cons;
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			HYPERVISOR_event_channel_op(EVTCHNOP_send, &event);
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			mb();
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		} while (data >= sizeof(console->out));
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		/* Copy the byte */
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		int ring_index = MASK_XENCONS_IDX(console->out_prod, console->out);
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		console->out[ring_index] = *message;
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		/* Ensure that the data really is in the ring before continuing */
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		wmb();
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		/* Increment input and output pointers */
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		console->out_prod++;
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	}
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	HYPERVISOR_event_channel_op(EVTCHNOP_send, &event);
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}
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static char diag_xen_getc(const struct diag *diag) {
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	assert(console->in_prod != console->in_cons);
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	int ring_index = MASK_XENCONS_IDX(console->in_cons, console->in);
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	char ch = console->in[ring_index];
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	rmb();
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	console->in_cons++;
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	return ch;
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}
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static int diag_xen_kbhit(const struct diag *diag) {
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	return console->in_prod != console->in_cons;
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}
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DIAG_OPS_DEF(
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	.init = diag_xen_init,
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	.putc = diag_xen_putc,
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	.getc = diag_xen_getc,
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	.kbhit = diag_xen_kbhit,
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);
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