drivers/gpu/drm/amd/amdgpu/iceland_ih.c - third_party/linux - Git at Google

 /*
  * Copyright 2014 Advanced Micro Devices, 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.
  *
  */
 #include <drm/drmP.h>
 #include "amdgpu.h"
 #include "amdgpu_ih.h"
 #include "vid.h"

 #include "oss/oss_2_4_d.h"
 #include "oss/oss_2_4_sh_mask.h"

 #include "bif/bif_5_1_d.h"
 #include "bif/bif_5_1_sh_mask.h"

 /*
  * Interrupts
  * Starting with r6xx, interrupts are handled via a ring buffer.
  * Ring buffers are areas of GPU accessible memory that the GPU
  * writes interrupt vectors into and the host reads vectors out of.
  * There is a rptr (read pointer) that determines where the
  * host is currently reading, and a wptr (write pointer)
  * which determines where the GPU has written.  When the
  * pointers are equal, the ring is idle.  When the GPU
  * writes vectors to the ring buffer, it increments the
  * wptr.  When there is an interrupt, the host then starts
  * fetching commands and processing them until the pointers are
  * equal again at which point it updates the rptr.
  */

 static void iceland_ih_set_interrupt_funcs(struct amdgpu_device *adev);

 /**
  * iceland_ih_enable_interrupts - Enable the interrupt ring buffer
  *
  * @adev: amdgpu_device pointer
  *
  * Enable the interrupt ring buffer (VI).
  */
 static void iceland_ih_enable_interrupts(struct amdgpu_device *adev)
 {
 	u32 ih_cntl = RREG32(mmIH_CNTL);
 	u32 ih_rb_cntl = RREG32(mmIH_RB_CNTL);

 	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, ENABLE_INTR, 1);
 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_ENABLE, 1);
 	WREG32(mmIH_CNTL, ih_cntl);
 	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
 	adev->irq.ih.enabled = true;
 }

 /**
  * iceland_ih_disable_interrupts - Disable the interrupt ring buffer
  *
  * @adev: amdgpu_device pointer
  *
  * Disable the interrupt ring buffer (VI).
  */
 static void iceland_ih_disable_interrupts(struct amdgpu_device *adev)
 {
 	u32 ih_rb_cntl = RREG32(mmIH_RB_CNTL);
 	u32 ih_cntl = RREG32(mmIH_CNTL);

 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_ENABLE, 0);
 	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, ENABLE_INTR, 0);
 	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
 	WREG32(mmIH_CNTL, ih_cntl);
 	/* set rptr, wptr to 0 */
 	WREG32(mmIH_RB_RPTR, 0);
 	WREG32(mmIH_RB_WPTR, 0);
 	adev->irq.ih.enabled = false;
 	adev->irq.ih.rptr = 0;
 }

 /**
  * iceland_ih_irq_init - init and enable the interrupt ring
  *
  * @adev: amdgpu_device pointer
  *
  * Allocate a ring buffer for the interrupt controller,
  * enable the RLC, disable interrupts, enable the IH
  * ring buffer and enable it (VI).
  * Called at device load and reume.
  * Returns 0 for success, errors for failure.
  */
 static int iceland_ih_irq_init(struct amdgpu_device *adev)
 {
 	int rb_bufsz;
 	u32 interrupt_cntl, ih_cntl, ih_rb_cntl;
 	u64 wptr_off;

 	/* disable irqs */
 	iceland_ih_disable_interrupts(adev);

 	/* setup interrupt control */
 	WREG32(mmINTERRUPT_CNTL2, adev->dummy_page_addr >> 8);
 	interrupt_cntl = RREG32(mmINTERRUPT_CNTL);
 	/* INTERRUPT_CNTL__IH_DUMMY_RD_OVERRIDE_MASK=0 - dummy read disabled with msi, enabled without msi
 	 * INTERRUPT_CNTL__IH_DUMMY_RD_OVERRIDE_MASK=1 - dummy read controlled by IH_DUMMY_RD_EN
 	 */
 	interrupt_cntl = REG_SET_FIELD(interrupt_cntl, INTERRUPT_CNTL, IH_DUMMY_RD_OVERRIDE, 0);
 	/* INTERRUPT_CNTL__IH_REQ_NONSNOOP_EN_MASK=1 if ring is in non-cacheable memory, e.g., vram */
 	interrupt_cntl = REG_SET_FIELD(interrupt_cntl, INTERRUPT_CNTL, IH_REQ_NONSNOOP_EN, 0);
 	WREG32(mmINTERRUPT_CNTL, interrupt_cntl);

 	/* Ring Buffer base. [39:8] of 40-bit address of the beginning of the ring buffer*/
 	WREG32(mmIH_RB_BASE, adev->irq.ih.gpu_addr >> 8);

 	rb_bufsz = order_base_2(adev->irq.ih.ring_size / 4);
 	ih_rb_cntl = REG_SET_FIELD(0, IH_RB_CNTL, WPTR_OVERFLOW_ENABLE, 1);
 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 1);
 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_SIZE, rb_bufsz);

 	/* Ring Buffer write pointer writeback. If enabled, IH_RB_WPTR register value is written to memory */
 	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, WPTR_WRITEBACK_ENABLE, 1);

 	/* set the writeback address whether it's enabled or not */
 	wptr_off = adev->wb.gpu_addr + (adev->irq.ih.wptr_offs * 4);
 	WREG32(mmIH_RB_WPTR_ADDR_LO, lower_32_bits(wptr_off));
 	WREG32(mmIH_RB_WPTR_ADDR_HI, upper_32_bits(wptr_off) & 0xFF);

 	WREG32(mmIH_RB_CNTL, ih_rb_cntl);

 	/* set rptr, wptr to 0 */
 	WREG32(mmIH_RB_RPTR, 0);
 	WREG32(mmIH_RB_WPTR, 0);

 	/* Default settings for IH_CNTL (disabled at first) */
 	ih_cntl = RREG32(mmIH_CNTL);
 	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, MC_VMID, 0);

 	if (adev->irq.msi_enabled)
 		ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, RPTR_REARM, 1);
 	WREG32(mmIH_CNTL, ih_cntl);

 	pci_set_master(adev->pdev);

 	/* enable interrupts */
 	iceland_ih_enable_interrupts(adev);

 	return 0;
 }

 /**
  * iceland_ih_irq_disable - disable interrupts
  *
  * @adev: amdgpu_device pointer
  *
  * Disable interrupts on the hw (VI).
  */
 static void iceland_ih_irq_disable(struct amdgpu_device *adev)
 {
 	iceland_ih_disable_interrupts(adev);

 	/* Wait and acknowledge irq */
 	mdelay(1);
 }

 /**
  * iceland_ih_get_wptr - get the IH ring buffer wptr
  *
  * @adev: amdgpu_device pointer
  *
  * Get the IH ring buffer wptr from either the register
  * or the writeback memory buffer (VI).  Also check for
  * ring buffer overflow and deal with it.
  * Used by cz_irq_process(VI).
  * Returns the value of the wptr.
  */
 static u32 iceland_ih_get_wptr(struct amdgpu_device *adev)
 {
 	u32 wptr, tmp;

 	wptr = le32_to_cpu(adev->wb.wb[adev->irq.ih.wptr_offs]);

 	if (REG_GET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW)) {
 		wptr = REG_SET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW, 0);
 		/* When a ring buffer overflow happen start parsing interrupt
 		 * from the last not overwritten vector (wptr + 16). Hopefully
 		 * this should allow us to catchup.
 		 */
 		dev_warn(adev->dev, "IH ring buffer overflow (0x%08X, 0x%08X, 0x%08X)\n",
 			wptr, adev->irq.ih.rptr, (wptr + 16) & adev->irq.ih.ptr_mask);
 		adev->irq.ih.rptr = (wptr + 16) & adev->irq.ih.ptr_mask;
 		tmp = RREG32(mmIH_RB_CNTL);
 		tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 1);
 		WREG32(mmIH_RB_CNTL, tmp);
 	}
 	return (wptr & adev->irq.ih.ptr_mask);
 }

 /**
  * iceland_ih_prescreen_iv - prescreen an interrupt vector
  *
  * @adev: amdgpu_device pointer
  *
  * Returns true if the interrupt vector should be further processed.
  */
 static bool iceland_ih_prescreen_iv(struct amdgpu_device *adev)
 {
 	u32 ring_index = adev->irq.ih.rptr >> 2;
 	u16 pasid;

 	switch (le32_to_cpu(adev->irq.ih.ring[ring_index]) & 0xff) {
 	case 146:
 	case 147:
 		pasid = le32_to_cpu(adev->irq.ih.ring[ring_index + 2]) >> 16;
 		if (!pasid || amdgpu_vm_pasid_fault_credit(adev, pasid))
 			return true;
 		break;
 	default:
 		/* Not a VM fault */
 		return true;
 	}

 	adev->irq.ih.rptr += 16;
 	return false;
 }

 /**
  * iceland_ih_decode_iv - decode an interrupt vector
  *
  * @adev: amdgpu_device pointer
  *
  * Decodes the interrupt vector at the current rptr
  * position and also advance the position.
  */
 static void iceland_ih_decode_iv(struct amdgpu_device *adev,
 				 struct amdgpu_iv_entry *entry)
 {
 	/* wptr/rptr are in bytes! */
 	u32 ring_index = adev->irq.ih.rptr >> 2;
 	uint32_t dw[4];

 	dw[0] = le32_to_cpu(adev->irq.ih.ring[ring_index + 0]);
 	dw[1] = le32_to_cpu(adev->irq.ih.ring[ring_index + 1]);
 	dw[2] = le32_to_cpu(adev->irq.ih.ring[ring_index + 2]);
 	dw[3] = le32_to_cpu(adev->irq.ih.ring[ring_index + 3]);

 	entry->client_id = AMDGPU_IH_CLIENTID_LEGACY;
 	entry->src_id = dw[0] & 0xff;
 	entry->src_data[0] = dw[1] & 0xfffffff;
 	entry->ring_id = dw[2] & 0xff;
 	entry->vmid = (dw[2] >> 8) & 0xff;
 	entry->pasid = (dw[2] >> 16) & 0xffff;

 	/* wptr/rptr are in bytes! */
 	adev->irq.ih.rptr += 16;
 }

 /**
  * iceland_ih_set_rptr - set the IH ring buffer rptr
  *
  * @adev: amdgpu_device pointer
  *
  * Set the IH ring buffer rptr.
  */
 static void iceland_ih_set_rptr(struct amdgpu_device *adev)
 {
 	WREG32(mmIH_RB_RPTR, adev->irq.ih.rptr);
 }

 static int iceland_ih_early_init(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
 	int ret;

 	ret = amdgpu_irq_add_domain(adev);
 	if (ret)
 		return ret;

 	iceland_ih_set_interrupt_funcs(adev);

 	return 0;
 }

 static int iceland_ih_sw_init(void *handle)
 {
 	int r;
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;

 	r = amdgpu_ih_ring_init(adev, 64 * 1024, false);
 	if (r)
 		return r;

 	r = amdgpu_irq_init(adev);

 	return r;
 }

 static int iceland_ih_sw_fini(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;

 	amdgpu_irq_fini(adev);
 	amdgpu_ih_ring_fini(adev);
 	amdgpu_irq_remove_domain(adev);

 	return 0;
 }

 static int iceland_ih_hw_init(void *handle)
 {
 	int r;
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;

 	r = iceland_ih_irq_init(adev);
 	if (r)
 		return r;

 	return 0;
 }

 static int iceland_ih_hw_fini(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;

 	iceland_ih_irq_disable(adev);

 	return 0;
 }

 static int iceland_ih_suspend(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;

 	return iceland_ih_hw_fini(adev);
 }

 static int iceland_ih_resume(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;

 	return iceland_ih_hw_init(adev);
 }

 static bool iceland_ih_is_idle(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
 	u32 tmp = RREG32(mmSRBM_STATUS);

 	if (REG_GET_FIELD(tmp, SRBM_STATUS, IH_BUSY))
 		return false;

 	return true;
 }

 static int iceland_ih_wait_for_idle(void *handle)
 {
 	unsigned i;
 	u32 tmp;
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;

 	for (i = 0; i < adev->usec_timeout; i++) {
 		/* read MC_STATUS */
 		tmp = RREG32(mmSRBM_STATUS);
 		if (!REG_GET_FIELD(tmp, SRBM_STATUS, IH_BUSY))
 			return 0;
 		udelay(1);
 	}
 	return -ETIMEDOUT;
 }

 static int iceland_ih_soft_reset(void *handle)
 {
 	u32 srbm_soft_reset = 0;
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
 	u32 tmp = RREG32(mmSRBM_STATUS);

 	if (tmp & SRBM_STATUS__IH_BUSY_MASK)
 		srbm_soft_reset = REG_SET_FIELD(srbm_soft_reset, SRBM_SOFT_RESET,
 						SOFT_RESET_IH, 1);

 	if (srbm_soft_reset) {
 		tmp = RREG32(mmSRBM_SOFT_RESET);
 		tmp |= srbm_soft_reset;
 		dev_info(adev->dev, "SRBM_SOFT_RESET=0x%08X\n", tmp);
 		WREG32(mmSRBM_SOFT_RESET, tmp);
 		tmp = RREG32(mmSRBM_SOFT_RESET);

 		udelay(50);

 		tmp &= ~srbm_soft_reset;
 		WREG32(mmSRBM_SOFT_RESET, tmp);
 		tmp = RREG32(mmSRBM_SOFT_RESET);

 		/* Wait a little for things to settle down */
 		udelay(50);
 	}

 	return 0;
 }

 static int iceland_ih_set_clockgating_state(void *handle,
 					  enum amd_clockgating_state state)
 {
 	return 0;
 }

 static int iceland_ih_set_powergating_state(void *handle,
 					  enum amd_powergating_state state)
 {
 	return 0;
 }

 static const struct amd_ip_funcs iceland_ih_ip_funcs = {
 	.name = "iceland_ih",
 	.early_init = iceland_ih_early_init,
 	.late_init = NULL,
 	.sw_init = iceland_ih_sw_init,
 	.sw_fini = iceland_ih_sw_fini,
 	.hw_init = iceland_ih_hw_init,
 	.hw_fini = iceland_ih_hw_fini,
 	.suspend = iceland_ih_suspend,
 	.resume = iceland_ih_resume,
 	.is_idle = iceland_ih_is_idle,
 	.wait_for_idle = iceland_ih_wait_for_idle,
 	.soft_reset = iceland_ih_soft_reset,
 	.set_clockgating_state = iceland_ih_set_clockgating_state,
 	.set_powergating_state = iceland_ih_set_powergating_state,
 };

 static const struct amdgpu_ih_funcs iceland_ih_funcs = {
 	.get_wptr = iceland_ih_get_wptr,
 	.prescreen_iv = iceland_ih_prescreen_iv,
 	.decode_iv = iceland_ih_decode_iv,
 	.set_rptr = iceland_ih_set_rptr
 };

 static void iceland_ih_set_interrupt_funcs(struct amdgpu_device *adev)
 {
 	if (adev->irq.ih_funcs == NULL)
 		adev->irq.ih_funcs = &iceland_ih_funcs;
 }

 const struct amdgpu_ip_block_version iceland_ih_ip_block =
 {
 	.type = AMD_IP_BLOCK_TYPE_IH,
 	.major = 2,
 	.minor = 4,
 	.rev = 0,
 	.funcs = &iceland_ih_ip_funcs,
 };
	/*
	* Copyright 2014 Advanced Micro Devices, 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.
	*
	*/
	#include <drm/drmP.h>
	#include "amdgpu.h"
	#include "amdgpu_ih.h"
	#include "vid.h"

	#include "oss/oss_2_4_d.h"
	#include "oss/oss_2_4_sh_mask.h"

	#include "bif/bif_5_1_d.h"
	#include "bif/bif_5_1_sh_mask.h"

	/*
	* Interrupts
	* Starting with r6xx, interrupts are handled via a ring buffer.
	* Ring buffers are areas of GPU accessible memory that the GPU
	* writes interrupt vectors into and the host reads vectors out of.
	* There is a rptr (read pointer) that determines where the
	* host is currently reading, and a wptr (write pointer)
	* which determines where the GPU has written. When the
	* pointers are equal, the ring is idle. When the GPU
	* writes vectors to the ring buffer, it increments the
	* wptr. When there is an interrupt, the host then starts
	* fetching commands and processing them until the pointers are
	* equal again at which point it updates the rptr.
	*/

	static void iceland_ih_set_interrupt_funcs(struct amdgpu_device *adev);

	/**
	* iceland_ih_enable_interrupts - Enable the interrupt ring buffer
	*
	* @adev: amdgpu_device pointer
	*
	* Enable the interrupt ring buffer (VI).
	*/
	static void iceland_ih_enable_interrupts(struct amdgpu_device *adev)
	{
	u32 ih_cntl = RREG32(mmIH_CNTL);
	u32 ih_rb_cntl = RREG32(mmIH_RB_CNTL);

	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, ENABLE_INTR, 1);
	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_ENABLE, 1);
	WREG32(mmIH_CNTL, ih_cntl);
	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
	adev->irq.ih.enabled = true;
	}

	/**
	* iceland_ih_disable_interrupts - Disable the interrupt ring buffer
	*
	* @adev: amdgpu_device pointer
	*
	* Disable the interrupt ring buffer (VI).
	*/
	static void iceland_ih_disable_interrupts(struct amdgpu_device *adev)
	{
	u32 ih_rb_cntl = RREG32(mmIH_RB_CNTL);
	u32 ih_cntl = RREG32(mmIH_CNTL);

	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_ENABLE, 0);
	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, ENABLE_INTR, 0);
	WREG32(mmIH_RB_CNTL, ih_rb_cntl);
	WREG32(mmIH_CNTL, ih_cntl);
	/* set rptr, wptr to 0 */
	WREG32(mmIH_RB_RPTR, 0);
	WREG32(mmIH_RB_WPTR, 0);
	adev->irq.ih.enabled = false;
	adev->irq.ih.rptr = 0;
	}

	/**
	* iceland_ih_irq_init - init and enable the interrupt ring
	*
	* @adev: amdgpu_device pointer
	*
	* Allocate a ring buffer for the interrupt controller,
	* enable the RLC, disable interrupts, enable the IH
	* ring buffer and enable it (VI).
	* Called at device load and reume.
	* Returns 0 for success, errors for failure.
	*/
	static int iceland_ih_irq_init(struct amdgpu_device *adev)
	{
	int rb_bufsz;
	u32 interrupt_cntl, ih_cntl, ih_rb_cntl;
	u64 wptr_off;

	/* disable irqs */
	iceland_ih_disable_interrupts(adev);

	/* setup interrupt control */
	WREG32(mmINTERRUPT_CNTL2, adev->dummy_page_addr >> 8);
	interrupt_cntl = RREG32(mmINTERRUPT_CNTL);
	/* INTERRUPT_CNTL__IH_DUMMY_RD_OVERRIDE_MASK=0 - dummy read disabled with msi, enabled without msi
	* INTERRUPT_CNTL__IH_DUMMY_RD_OVERRIDE_MASK=1 - dummy read controlled by IH_DUMMY_RD_EN
	*/
	interrupt_cntl = REG_SET_FIELD(interrupt_cntl, INTERRUPT_CNTL, IH_DUMMY_RD_OVERRIDE, 0);
	/* INTERRUPT_CNTL__IH_REQ_NONSNOOP_EN_MASK=1 if ring is in non-cacheable memory, e.g., vram */
	interrupt_cntl = REG_SET_FIELD(interrupt_cntl, INTERRUPT_CNTL, IH_REQ_NONSNOOP_EN, 0);
	WREG32(mmINTERRUPT_CNTL, interrupt_cntl);

	/* Ring Buffer base. [39:8] of 40-bit address of the beginning of the ring buffer*/
	WREG32(mmIH_RB_BASE, adev->irq.ih.gpu_addr >> 8);

	rb_bufsz = order_base_2(adev->irq.ih.ring_size / 4);
	ih_rb_cntl = REG_SET_FIELD(0, IH_RB_CNTL, WPTR_OVERFLOW_ENABLE, 1);
	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 1);
	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, RB_SIZE, rb_bufsz);

	/* Ring Buffer write pointer writeback. If enabled, IH_RB_WPTR register value is written to memory */
	ih_rb_cntl = REG_SET_FIELD(ih_rb_cntl, IH_RB_CNTL, WPTR_WRITEBACK_ENABLE, 1);

	/* set the writeback address whether it's enabled or not */
	wptr_off = adev->wb.gpu_addr + (adev->irq.ih.wptr_offs * 4);
	WREG32(mmIH_RB_WPTR_ADDR_LO, lower_32_bits(wptr_off));
	WREG32(mmIH_RB_WPTR_ADDR_HI, upper_32_bits(wptr_off) & 0xFF);

	WREG32(mmIH_RB_CNTL, ih_rb_cntl);

	/* set rptr, wptr to 0 */
	WREG32(mmIH_RB_RPTR, 0);
	WREG32(mmIH_RB_WPTR, 0);

	/* Default settings for IH_CNTL (disabled at first) */
	ih_cntl = RREG32(mmIH_CNTL);
	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, MC_VMID, 0);

	if (adev->irq.msi_enabled)
	ih_cntl = REG_SET_FIELD(ih_cntl, IH_CNTL, RPTR_REARM, 1);
	WREG32(mmIH_CNTL, ih_cntl);

	pci_set_master(adev->pdev);

	/* enable interrupts */
	iceland_ih_enable_interrupts(adev);

	return 0;
	}

	/**
	* iceland_ih_irq_disable - disable interrupts
	*
	* @adev: amdgpu_device pointer
	*
	* Disable interrupts on the hw (VI).
	*/
	static void iceland_ih_irq_disable(struct amdgpu_device *adev)
	{
	iceland_ih_disable_interrupts(adev);

	/* Wait and acknowledge irq */
	mdelay(1);
	}

	/**
	* iceland_ih_get_wptr - get the IH ring buffer wptr
	*
	* @adev: amdgpu_device pointer
	*
	* Get the IH ring buffer wptr from either the register
	* or the writeback memory buffer (VI). Also check for
	* ring buffer overflow and deal with it.
	* Used by cz_irq_process(VI).
	* Returns the value of the wptr.
	*/
	static u32 iceland_ih_get_wptr(struct amdgpu_device *adev)
	{
	u32 wptr, tmp;

	wptr = le32_to_cpu(adev->wb.wb[adev->irq.ih.wptr_offs]);

	if (REG_GET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW)) {
	wptr = REG_SET_FIELD(wptr, IH_RB_WPTR, RB_OVERFLOW, 0);
	/* When a ring buffer overflow happen start parsing interrupt
	* from the last not overwritten vector (wptr + 16). Hopefully
	* this should allow us to catchup.
	*/
	dev_warn(adev->dev, "IH ring buffer overflow (0x%08X, 0x%08X, 0x%08X)\n",
	wptr, adev->irq.ih.rptr, (wptr + 16) & adev->irq.ih.ptr_mask);
	adev->irq.ih.rptr = (wptr + 16) & adev->irq.ih.ptr_mask;
	tmp = RREG32(mmIH_RB_CNTL);
	tmp = REG_SET_FIELD(tmp, IH_RB_CNTL, WPTR_OVERFLOW_CLEAR, 1);
	WREG32(mmIH_RB_CNTL, tmp);
	}
	return (wptr & adev->irq.ih.ptr_mask);
	}

	/**
	* iceland_ih_prescreen_iv - prescreen an interrupt vector
	*
	* @adev: amdgpu_device pointer
	*
	* Returns true if the interrupt vector should be further processed.
	*/
	static bool iceland_ih_prescreen_iv(struct amdgpu_device *adev)
	{
	u32 ring_index = adev->irq.ih.rptr >> 2;
	u16 pasid;

	switch (le32_to_cpu(adev->irq.ih.ring[ring_index]) & 0xff) {
	case 146:
	case 147:
	pasid = le32_to_cpu(adev->irq.ih.ring[ring_index + 2]) >> 16;
	if (!pasid \|\| amdgpu_vm_pasid_fault_credit(adev, pasid))
	return true;
	break;
	default:
	/* Not a VM fault */
	return true;
	}

	adev->irq.ih.rptr += 16;
	return false;
	}

	/**
	* iceland_ih_decode_iv - decode an interrupt vector
	*
	* @adev: amdgpu_device pointer
	*
	* Decodes the interrupt vector at the current rptr
	* position and also advance the position.
	*/
	static void iceland_ih_decode_iv(struct amdgpu_device *adev,
	struct amdgpu_iv_entry *entry)
	{
	/* wptr/rptr are in bytes! */
	u32 ring_index = adev->irq.ih.rptr >> 2;
	uint32_t dw[4];

	dw[0] = le32_to_cpu(adev->irq.ih.ring[ring_index + 0]);
	dw[1] = le32_to_cpu(adev->irq.ih.ring[ring_index + 1]);
	dw[2] = le32_to_cpu(adev->irq.ih.ring[ring_index + 2]);
	dw[3] = le32_to_cpu(adev->irq.ih.ring[ring_index + 3]);

	entry->client_id = AMDGPU_IH_CLIENTID_LEGACY;
	entry->src_id = dw[0] & 0xff;
	entry->src_data[0] = dw[1] & 0xfffffff;
	entry->ring_id = dw[2] & 0xff;
	entry->vmid = (dw[2] >> 8) & 0xff;
	entry->pasid = (dw[2] >> 16) & 0xffff;

	/* wptr/rptr are in bytes! */
	adev->irq.ih.rptr += 16;
	}

	/**
	* iceland_ih_set_rptr - set the IH ring buffer rptr
	*
	* @adev: amdgpu_device pointer
	*
	* Set the IH ring buffer rptr.
	*/
	static void iceland_ih_set_rptr(struct amdgpu_device *adev)
	{
	WREG32(mmIH_RB_RPTR, adev->irq.ih.rptr);
	}

	static int iceland_ih_early_init(void *handle)
	{
	struct amdgpu_device adev = (struct amdgpu_device )handle;
	int ret;

	ret = amdgpu_irq_add_domain(adev);
	if (ret)
	return ret;

	iceland_ih_set_interrupt_funcs(adev);

	return 0;
	}

	static int iceland_ih_sw_init(void *handle)
	{
	int r;
	struct amdgpu_device adev = (struct amdgpu_device )handle;

	r = amdgpu_ih_ring_init(adev, 64 * 1024, false);
	if (r)
	return r;

	r = amdgpu_irq_init(adev);

	return r;
	}

	static int iceland_ih_sw_fini(void *handle)
	{
	struct amdgpu_device adev = (struct amdgpu_device )handle;

	amdgpu_irq_fini(adev);
	amdgpu_ih_ring_fini(adev);
	amdgpu_irq_remove_domain(adev);

	return 0;
	}

	static int iceland_ih_hw_init(void *handle)
	{
	int r;
	struct amdgpu_device adev = (struct amdgpu_device )handle;

	r = iceland_ih_irq_init(adev);
	if (r)
	return r;

	return 0;
	}

	static int iceland_ih_hw_fini(void *handle)
	{
	struct amdgpu_device adev = (struct amdgpu_device )handle;

	iceland_ih_irq_disable(adev);

	return 0;
	}

	static int iceland_ih_suspend(void *handle)
	{
	struct amdgpu_device adev = (struct amdgpu_device )handle;

	return iceland_ih_hw_fini(adev);
	}

	static int iceland_ih_resume(void *handle)
	{
	struct amdgpu_device adev = (struct amdgpu_device )handle;

	return iceland_ih_hw_init(adev);
	}

	static bool iceland_ih_is_idle(void *handle)
	{
	struct amdgpu_device adev = (struct amdgpu_device )handle;
	u32 tmp = RREG32(mmSRBM_STATUS);

	if (REG_GET_FIELD(tmp, SRBM_STATUS, IH_BUSY))
	return false;

	return true;
	}

	static int iceland_ih_wait_for_idle(void *handle)
	{
	unsigned i;
	u32 tmp;
	struct amdgpu_device adev = (struct amdgpu_device )handle;

	for (i = 0; i < adev->usec_timeout; i++) {
	/* read MC_STATUS */
	tmp = RREG32(mmSRBM_STATUS);
	if (!REG_GET_FIELD(tmp, SRBM_STATUS, IH_BUSY))
	return 0;
	udelay(1);
	}
	return -ETIMEDOUT;
	}

	static int iceland_ih_soft_reset(void *handle)
	{
	u32 srbm_soft_reset = 0;
	struct amdgpu_device adev = (struct amdgpu_device )handle;
	u32 tmp = RREG32(mmSRBM_STATUS);

	if (tmp & SRBM_STATUS__IH_BUSY_MASK)
	srbm_soft_reset = REG_SET_FIELD(srbm_soft_reset, SRBM_SOFT_RESET,
	SOFT_RESET_IH, 1);

	if (srbm_soft_reset) {
	tmp = RREG32(mmSRBM_SOFT_RESET);
	tmp \|= srbm_soft_reset;
	dev_info(adev->dev, "SRBM_SOFT_RESET=0x%08X\n", tmp);
	WREG32(mmSRBM_SOFT_RESET, tmp);
	tmp = RREG32(mmSRBM_SOFT_RESET);

	udelay(50);

	tmp &= ~srbm_soft_reset;
	WREG32(mmSRBM_SOFT_RESET, tmp);
	tmp = RREG32(mmSRBM_SOFT_RESET);

	/* Wait a little for things to settle down */
	udelay(50);
	}

	return 0;
	}

	static int iceland_ih_set_clockgating_state(void *handle,
	enum amd_clockgating_state state)
	{
	return 0;
	}

	static int iceland_ih_set_powergating_state(void *handle,
	enum amd_powergating_state state)
	{
	return 0;
	}

	static const struct amd_ip_funcs iceland_ih_ip_funcs = {
	.name = "iceland_ih",
	.early_init = iceland_ih_early_init,
	.late_init = NULL,
	.sw_init = iceland_ih_sw_init,
	.sw_fini = iceland_ih_sw_fini,
	.hw_init = iceland_ih_hw_init,
	.hw_fini = iceland_ih_hw_fini,
	.suspend = iceland_ih_suspend,
	.resume = iceland_ih_resume,
	.is_idle = iceland_ih_is_idle,
	.wait_for_idle = iceland_ih_wait_for_idle,
	.soft_reset = iceland_ih_soft_reset,
	.set_clockgating_state = iceland_ih_set_clockgating_state,
	.set_powergating_state = iceland_ih_set_powergating_state,
	};

	static const struct amdgpu_ih_funcs iceland_ih_funcs = {
	.get_wptr = iceland_ih_get_wptr,
	.prescreen_iv = iceland_ih_prescreen_iv,
	.decode_iv = iceland_ih_decode_iv,
	.set_rptr = iceland_ih_set_rptr
	};

	static void iceland_ih_set_interrupt_funcs(struct amdgpu_device *adev)
	{
	if (adev->irq.ih_funcs == NULL)
	adev->irq.ih_funcs = &iceland_ih_funcs;
	}

	const struct amdgpu_ip_block_version iceland_ih_ip_block =
	{
	.type = AMD_IP_BLOCK_TYPE_IH,
	.major = 2,
	.minor = 4,
	.rev = 0,
	.funcs = &iceland_ih_ip_funcs,
	};