/* fuc microcode for nvc0 PGRAPH/GPC
 *
 * Copyright 2011 Red Hat Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Authors: Ben Skeggs
 */

/* TODO
 * - bracket certain functions with scratch writes, useful for debugging
 * - watchdog timer around ctx operations
 */

#ifdef INCLUDE_DATA
gpc_mmio_list_head:	.b32 #mmio_list_base
gpc_mmio_list_tail:
tpc_mmio_list_head:	.b32 #mmio_list_base
tpc_mmio_list_tail:
unk_mmio_list_head:	.b32 #mmio_list_base
unk_mmio_list_tail:	.b32 #mmio_list_base

gpc_id:			.b32 0

tpc_count:		.b32 0
tpc_mask:		.b32 0

#if NV_PGRAPH_GPCX_UNK__SIZE > 0
unk_count:		.b32 0
unk_mask:		.b32 0
#endif

cmd_queue:		queue_init

mmio_list_base:
#endif

#ifdef INCLUDE_CODE
// reports an exception to the host
//
// In: $r15 error code (see nvc0.fuc)
//
error:
	push $r14
	nv_wr32(NV_PGRAPH_FECS_CC_SCRATCH_VAL(5), $r15)
	mov $r15 1
	nv_wr32(NV_PGRAPH_FECS_INTR_UP_SET, $r15)
	pop $r14
	ret

// GPC fuc initialisation, executed by triggering ucode start, will
// fall through to main loop after completion.
//
// Input:
//   CC_SCRATCH[1]: context base
//
// Output:
//   CC_SCRATCH[0]:
//	     31:31: set to signal completion
//   CC_SCRATCH[1]:
//	      31:0: GPC context size
//
init:
	clear b32 $r0
	mov $sp $r0

	// enable fifo access
	mov $r2 NV_PGRAPH_GPCX_GPCCS_ACCESS_FIFO
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_ACCESS, 0, $r2)

	// setup i0 handler, and route all interrupts to it
	mov $r1 #ih
	mov $iv0 $r1
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_INTR_ROUTE, 0, $r0)

	// enable fifo interrupt
	mov $r2 NV_PGRAPH_GPCX_GPCCS_INTR_EN_SET_FIFO
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_INTR_EN_SET, 0, $r2)

	// enable interrupts
	bset $flags ie0

	// figure out which GPC we are, and how many TPCs we have
	nv_iord($r2, NV_PGRAPH_GPCX_GPCCS_UNITS, 0)
	mov $r3 1
	and $r2 0x1f
	shl b32 $r3 $r2
	sub b32 $r3 1
	st b32 D[$r0 + #tpc_count] $r2
	st b32 D[$r0 + #tpc_mask] $r3
	nv_iord($r2, NV_PGRAPH_GPCX_GPCCS_MYINDEX, 0)
	st b32 D[$r0 + #gpc_id] $r2

#if NV_PGRAPH_GPCX_UNK__SIZE > 0
	// figure out which, and how many, UNKs are actually present
	imm32($r14, 0x500c30)
	clear b32 $r2
	clear b32 $r3
	clear b32 $r4
	init_unk_loop:
		call(nv_rd32)
		cmp b32 $r15 0
		bra z #init_unk_next
			mov $r15 1
			shl b32 $r15 $r2
			or $r4 $r15
			add b32 $r3 1
		init_unk_next:
		add b32 $r2 1
		add b32 $r14 4
		cmp b32 $r2 NV_PGRAPH_GPCX_UNK__SIZE
		bra ne #init_unk_loop
	init_unk_done:
	st b32 D[$r0 + #unk_count] $r3
	st b32 D[$r0 + #unk_mask] $r4
#endif

	// initialise context base, and size tracking
	nv_iord($r2, NV_PGRAPH_GPCX_GPCCS_CC_SCRATCH_VAL(1), 0)
	clear b32 $r3		// track GPC context size here

	// set mmctx base addresses now so we don't have to do it later,
	// they don't currently ever change
	shr b32 $r5 $r2 8
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_MMCTX_SAVE_SWBASE, 0, $r5)
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_MMCTX_LOAD_SWBASE, 0, $r5)

	// calculate GPC mmio context size
	ld b32 $r14 D[$r0 + #gpc_mmio_list_head]
	ld b32 $r15 D[$r0 + #gpc_mmio_list_tail]
	call(mmctx_size)
	add b32 $r2 $r15
	add b32 $r3 $r15

	// calculate per-TPC mmio context size
	ld b32 $r14 D[$r0 + #tpc_mmio_list_head]
	ld b32 $r15 D[$r0 + #tpc_mmio_list_tail]
	call(mmctx_size)
	ld b32 $r14 D[$r0 + #tpc_count]
	mulu $r14 $r15
	add b32 $r2 $r14
	add b32 $r3 $r14

#if NV_PGRAPH_GPCX_UNK__SIZE > 0
	// calculate per-UNK mmio context size
	ld b32 $r14 D[$r0 + #unk_mmio_list_head]
	ld b32 $r15 D[$r0 + #unk_mmio_list_tail]
	call(mmctx_size)
	ld b32 $r14 D[$r0 + #unk_count]
	mulu $r14 $r15
	add b32 $r2 $r14
	add b32 $r3 $r14
#endif

	// round up base/size to 256 byte boundary (for strand SWBASE)
	shr b32 $r3 2
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_MMCTX_LOAD_COUNT, 0, $r3) // wtf for?!
	shr b32 $r2 8
	shr b32 $r3 6
	add b32 $r2 1
	add b32 $r3 1
	shl b32 $r2 8
	shl b32 $r3 8

	// calculate size of strand context data
	mov b32 $r15 $r2
	call(strand_ctx_init)
	add b32 $r3 $r15

	// save context size, and tell HUB we're done
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_CC_SCRATCH_VAL(1), 0, $r3)
	clear b32 $r2
	bset $r2 31
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_CC_SCRATCH_SET(0), 0, $r2)

// Main program loop, very simple, sleeps until woken up by the interrupt
// handler, pulls a command from the queue and executes its handler
//
main:
	bset $flags $p0
	sleep $p0
	mov $r13 #cmd_queue
	call(queue_get)
	bra $p1 #main

	// 0x0000-0x0003 are all context transfers
	cmpu b32 $r14 0x04
	bra nc #main_not_ctx_xfer
		// fetch $flags and mask off $p1/$p2
		mov $r1 $flags
		mov $r2 0x0006
		not b32 $r2
		and $r1 $r2
		// set $p1/$p2 according to transfer type
		shl b32 $r14 1
		or $r1 $r14
		mov $flags $r1
		// transfer context data
		call(ctx_xfer)
		bra #main

	main_not_ctx_xfer:
	shl b32 $r15 $r14 16
	or $r15 E_BAD_COMMAND
	call(error)
	bra #main

// interrupt handler
ih:
	push $r8
	mov $r8 $flags
	push $r8
	push $r9
	push $r10
	push $r11
	push $r13
	push $r14
	push $r15
	clear b32 $r0

	// incoming fifo command?
	nv_iord($r10, NV_PGRAPH_GPCX_GPCCS_INTR, 0)
	and $r11 $r10 NV_PGRAPH_GPCX_GPCCS_INTR_FIFO
	bra e #ih_no_fifo
		// queue incoming fifo command for later processing
		mov $r13 #cmd_queue
		nv_iord($r14, NV_PGRAPH_GPCX_GPCCS_FIFO_CMD, 0)
		nv_iord($r15, NV_PGRAPH_GPCX_GPCCS_FIFO_DATA, 0)
		call(queue_put)
		mov $r14 1
		nv_iowr(NV_PGRAPH_GPCX_GPCCS_FIFO_ACK, 0, $r14)

	// ack, and wake up main()
	ih_no_fifo:
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_INTR_ACK, 0, $r10)

	pop $r15
	pop $r14
	pop $r13
	pop $r11
	pop $r10
	pop $r9
	pop $r8
	mov $flags $r8
	pop $r8
	bclr $flags $p0
	iret

// Set this GPC's bit in HUB_BAR, used to signal completion of various
// activities to the HUB fuc
//
hub_barrier_done:
	mov $r15 1
	ld b32 $r14 D[$r0 + #gpc_id]
	shl b32 $r15 $r14
	nv_wr32(0x409418, $r15)	// 0x409418 - HUB_BAR_SET
	ret

// Disables various things, waits a bit, and re-enables them..
//
// Not sure how exactly this helps, perhaps "ENABLE" is not such a
// good description for the bits we turn off?  Anyways, without this,
// funny things happen.
//
ctx_redswitch:
	mov $r15 NV_PGRAPH_GPCX_GPCCS_RED_SWITCH_POWER
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_RED_SWITCH, 0, $r15)
	mov $r14 8
	ctx_redswitch_delay:
		sub b32 $r14 1
		bra ne #ctx_redswitch_delay
	or $r15 NV_PGRAPH_GPCX_GPCCS_RED_SWITCH_UNK11
	or $r15 NV_PGRAPH_GPCX_GPCCS_RED_SWITCH_ENABLE
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_RED_SWITCH, 0, $r15)
	ret

// Transfer GPC context data between GPU and storage area
//
// In: $r15 context base address
//     $p1 clear on save, set on load
//     $p2 set if opposite direction done/will be done, so:
//		on save it means: "a load will follow this save"
//		on load it means: "a save preceeded this load"
//
ctx_xfer:
	// set context base address
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_MEM_BASE, 0, $r15)
	bra not $p1 #ctx_xfer_not_load
		call(ctx_redswitch)
	ctx_xfer_not_load:

	// strands
	call(strand_pre)
	clear b32 $r2
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_STRAND_SELECT, 0x3f, $r2)
	xbit $r2 $flags $p1	// SAVE/LOAD
	add b32 $r2 NV_PGRAPH_GPCX_GPCCS_STRAND_CMD_SAVE
	nv_iowr(NV_PGRAPH_GPCX_GPCCS_STRAND_CMD, 0x3f, $r2)

	// mmio context
	xbit $r10 $flags $p1	// direction
	or $r10 2		// first
	imm32($r11,0x500000)
	ld b32 $r12 D[$r0 + #gpc_id]
	shl b32 $r12 15
	add b32 $r11 $r12	// base = NV_PGRAPH_GPCn
	ld b32 $r12 D[$r0 + #gpc_mmio_list_head]
	ld b32 $r13 D[$r0 + #gpc_mmio_list_tail]
	mov $r14 0		// not multi
	call(mmctx_xfer)

	// per-TPC mmio context
	xbit $r10 $flags $p1	// direction
#if !NV_PGRAPH_GPCX_UNK__SIZE
	or $r10 4		// last
#endif
	imm32($r11, 0x504000)
	ld b32 $r12 D[$r0 + #gpc_id]
	shl b32 $r12 15
	add b32 $r11 $r12	// base = NV_PGRAPH_GPCn_TPC0
	ld b32 $r12 D[$r0 + #tpc_mmio_list_head]
	ld b32 $r13 D[$r0 + #tpc_mmio_list_tail]
	ld b32 $r15 D[$r0 + #tpc_mask]
	mov $r14 0x800		// stride = 0x800
	call(mmctx_xfer)

#if NV_PGRAPH_GPCX_UNK__SIZE > 0
	// per-UNK mmio context
	xbit $r10 $flags $p1	// direction
	or $r10 4		// last
	imm32($r11, 0x503000)
	ld b32 $r12 D[$r0 + #gpc_id]
	shl b32 $r12 15
	add b32 $r11 $r12	// base = NV_PGRAPH_GPCn_UNK0
	ld b32 $r12 D[$r0 + #unk_mmio_list_head]
	ld b32 $r13 D[$r0 + #unk_mmio_list_tail]
	ld b32 $r15 D[$r0 + #unk_mask]
	mov $r14 0x200		// stride = 0x200
	call(mmctx_xfer)
#endif

	// wait for strands to finish
	call(strand_wait)

	// if load, or a save without a load following, do some
	// unknown stuff that's done after finishing a block of
	// strand commands
	bra $p1 #ctx_xfer_post
	bra not $p2 #ctx_xfer_done
	ctx_xfer_post:
		call(strand_post)

	// mark completion in HUB's barrier
	ctx_xfer_done:
	call(hub_barrier_done)
	ret
#endif