[Intel-gfx] [PATCH v4] drm/i915 : Added Programming of the MOCS

Peter Antoine peter.antoine at intel.com
Tue Jun 30 06:11:23 PDT 2015


On Mon, 29 Jun 2015, Peter Antoine wrote:

> On Thu, 25 Jun 2015, Francisco Jerez wrote:
>
>> Peter Antoine <peter.antoine at intel.com> writes:
>>
>>> This change adds the programming of the MOCS registers to the gen 9+
>>> platforms. This change set programs the MOCS register values to a set
>>> of values that are defined to be optimal.
>>>
>>> It creates a fixed register set that is programmed across the different
>>> engines so that all engines have the same table. This is done as the
>>> main RCS context only holds the registers for itself and the shared
>>> L3 values. By trying to keep the registers consistent across the
>>> different engines it should make the programming for the registers
>>> consistent.
>>>
>>> v2:
>>> -'static const' for private data structures and style changes.(Matt 
> Turner)
>>> v3:
>>> - Make the tables "slightly" more readable. (Damien Lespiau)
>>> - Updated tables fix performance regression.
>>> v4:
>>> - Code formatting. (Chris Wilson)
>>> - re-privatised mocs code. (Daniel Vetter)
>>>
>>> Signed-off-by: Peter Antoine <peter.antoine at intel.com>
>>> ---
>>>  drivers/gpu/drm/i915/Makefile     |   1 +
>>>  drivers/gpu/drm/i915/i915_reg.h   |   9 +
>>>  drivers/gpu/drm/i915/intel_lrc.c  |  10 +-
>>>  drivers/gpu/drm/i915/intel_lrc.h  |   4 +
>>>  drivers/gpu/drm/i915/intel_mocs.c | 373 
> ++++++++++++++++++++++++++++++++++++++
>>>  drivers/gpu/drm/i915/intel_mocs.h |  64 +++++++
>>>  6 files changed, 460 insertions(+), 1 deletion(-)
>>>  create mode 100644 drivers/gpu/drm/i915/intel_mocs.c
>>>  create mode 100644 drivers/gpu/drm/i915/intel_mocs.h
>>>
>>> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
>>> index b7ddf48..c781e19 100644
>>> --- a/drivers/gpu/drm/i915/Makefile
>>> +++ b/drivers/gpu/drm/i915/Makefile
>>> @@ -35,6 +35,7 @@ i915-y += i915_cmd_parser.o \
>>>  	  i915_irq.o \
>>>  	  i915_trace_points.o \
>>>  	  intel_lrc.o \
>>> +	  intel_mocs.o \
>>>  	  intel_ringbuffer.o \
>>>  	  intel_uncore.o
>>>
>>> diff --git a/drivers/gpu/drm/i915/i915_reg.h 
> b/drivers/gpu/drm/i915/i915_reg.h
>>> index 7213224..3a435b5 100644
>>> --- a/drivers/gpu/drm/i915/i915_reg.h
>>> +++ b/drivers/gpu/drm/i915/i915_reg.h
>>> @@ -7829,4 +7829,13 @@ enum skl_disp_power_wells {
>>>  #define _PALETTE_A (dev_priv->info.display_mmio_offset + 0xa000)
>>>  #define _PALETTE_B (dev_priv->info.display_mmio_offset + 0xa800)
>>>
>>> +/* MOCS (Memory Object Control State) registers */
>>> +#define GEN9_LNCFCMOCS0		(0xB020)	/* L3 Cache Control 
> base */
>>> +
>>> +#define GEN9_GFX_MOCS_0		(0xc800)	/* Graphics MOCS base 
> register*/
>>> +#define GEN9_MFX0_MOCS_0	(0xc900)	/* Media 0 MOCS base 
> register*/
>>> +#define GEN9_MFX1_MOCS_0	(0xcA00)	/* Media 1 MOCS base 
> register*/
>>> +#define GEN9_VEBOX_MOCS_0	(0xcB00)	/* Video MOCS base register*/
>>> +#define GEN9_BLT_MOCS_0		(0xcc00)	/* Blitter MOCS base 
> register*/
>>> +
>>>  #endif /* _I915_REG_H_ */
>>> diff --git a/drivers/gpu/drm/i915/intel_lrc.c 
> b/drivers/gpu/drm/i915/intel_lrc.c
>>> index 9f5485d..73b919d 100644
>>> --- a/drivers/gpu/drm/i915/intel_lrc.c
>>> +++ b/drivers/gpu/drm/i915/intel_lrc.c
>>> @@ -135,6 +135,7 @@
>>>  #include <drm/drmP.h>
>>>  #include <drm/i915_drm.h>
>>>  #include "i915_drv.h"
>>> +#include "intel_mocs.h"
>>>
>>>  #define GEN9_LR_CONTEXT_RENDER_SIZE (22 * PAGE_SIZE)
>>>  #define GEN8_LR_CONTEXT_RENDER_SIZE (20 * PAGE_SIZE)
>>> @@ -796,7 +797,7 @@ static int logical_ring_prepare(struct 
> intel_ringbuffer *ringbuf,
>>>   *
>>>   * Return: non-zero if the ringbuffer is not ready to be written to.
>>>   */
>>> -static int intel_logical_ring_begin(struct intel_ringbuffer *ringbuf,
>>> +int intel_logical_ring_begin(struct intel_ringbuffer *ringbuf,
>>>  				    struct intel_context *ctx, int 
> num_dwords)
>>>  {
>>>  	struct intel_engine_cs *ring = ringbuf->ring;
>>> @@ -1379,6 +1380,13 @@ static int gen8_init_rcs_context(struct 
> intel_engine_cs *ring,
>>>  	if (ret)
>>>  		return ret;
>>>
>>> +	/*
>>> +	 * Failing to program the MOCS is non-fatal.The system will not
>>> +	 * run at peak performance. So generate a warning and carry on.
>>> +	 */
>>> +	if (gen9_program_mocs(ring, ctx) != 0)
>>> +		DRM_ERROR("MOCS failed to program: expect performance 
> issues.");
>>> +
>>>  	return intel_lr_context_render_state_init(ring, ctx);
>>>  }
>>>
>>> diff --git a/drivers/gpu/drm/i915/intel_lrc.h 
> b/drivers/gpu/drm/i915/intel_lrc.h
>>> index 04d3a6d..dbbd6af 100644
>>> --- a/drivers/gpu/drm/i915/intel_lrc.h
>>> +++ b/drivers/gpu/drm/i915/intel_lrc.h
>>> @@ -44,6 +44,10 @@ int intel_logical_rings_init(struct drm_device *dev);
>>>
>>>  int logical_ring_flush_all_caches(struct intel_ringbuffer *ringbuf,
>>>  				  struct intel_context *ctx);
>>> +
>>> +int intel_logical_ring_begin(struct intel_ringbuffer *ringbuf,
>>> +				    struct intel_context *ctx, int 
> num_dwords);
>>> +
>>>  /**
>>>   * intel_logical_ring_advance() - advance the ringbuffer tail
>>>   * @ringbuf: Ringbuffer to advance.
>>> diff --git a/drivers/gpu/drm/i915/intel_mocs.c 
> b/drivers/gpu/drm/i915/intel_mocs.c
>>> new file mode 100644
>>> index 0000000..7c09e67
>>> --- /dev/null
>>> +++ b/drivers/gpu/drm/i915/intel_mocs.c
>>> @@ -0,0 +1,373 @@
>>> +/*
>>> + * Copyright (c) 2015 Intel Corporation
>>> + *
>>> + * 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 (including the 
> next
>>> + * paragraph) 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 AUTHORS OR COPYRIGHT HOLDERS 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:
>>> + *    Peter Antoine <peter.antoine at intel.com>
>>> + */
>>> +
>>> +#include "intel_mocs.h"
>>> +#include "intel_lrc.h"
>>> +#include "intel_ringbuffer.h"
>>> +
>>> +/* structures required */
>>> +struct drm_i915_mocs_entry {
>>> +	u32	control_value;
>>> +	u16	l3cc_value;
>>> +};
>>> +
>>> +struct drm_i915_mocs_table {
>>> +	u32					size;
>>> +	const struct drm_i915_mocs_entry	*table;
>>> +};
>>> +
>>> +/* Defines for the tables (XXX_MOCS_0 - XXX_MOCS_63) */
>>> +#define	MOCS_CACHEABILITY(value)	(value << 0)
>>> +#define	MOCS_TGT_CACHE(value)		(value << 2)
>>> +#define	MOCS_LRUM(value)		(value << 4)
>>> +#define	MOCS_AOM(value)			(value << 6)
>>> +#define	MOCS_LECC_ESC(value)		(value << 7)
>>> +#define	MOCS_LECC_SCC(value)		(value << 8)
>>> +#define	MOC_PFM(value)			(value << 11)
>>> +#define	MOCS_SCF(value)			(value << 14)
>>> +
>>> +/* Defines for the tables (LNCFMOCS0 - LNCFMOCS31) - two entries per word 
> */
>>> +#define	MOCS_ESC(value)			(value << 0)
>>> +#define	MOCS_SCC(value)			(value << 1)
>>> +#define	MOCS_L3_CACHEABILITY(value)	(value << 4)
>>> +
>>> +/* Helper defines */
>>> +#define GEN9_NUM_MOCS_RINGS	(5)	/* Number of mocs engines to program 
> */
>>> +#define GEN9_NUM_MOCS_ENTRIES	(63)	/* 63 out of 64 - 64 is rsvrd 
> */
>>> +
>>> +/* EDRAM Caching options */
>>> +#define EDRAM_PAGETABLE		(0)
>>> +#define EDRAM_UC		(1)
>>> +#define EDRAM_RESERVED		(2)
>>
>> According to the BSpec this is WT rather than reserved?a
> Just checked the Bspec and you are correct, changing the text.
> As well as for the items below.
Just to add - I was looking at the wrong gen.
>>
>>> +#define EDRAM_WB		(3)
>>> +
>>> +/* L3 Caching options */
>>> +#define L3_DIRECT		(0)
>>> +#define L3_UC			(1)
>>> +#define L3_RESERVED		(2)
>>> +#define L3_WB			(3)
>>> +
>>> +/* target cache */
>>> +#define ELLC			(0)
>>
>> BSpec says that this is "Use TC/LRU controls from page table", but upon
>> a closer look it seems like the BSpec is wrong and your patch is
>> correct.  Can you confirm that this is what you intended?
> These values look good, they are bits 3:2 for the XXX_MOCS_N registers 
> (c800) and friends. 
>>
>>> +#define LLC			(1)
>>> +#define LLC_ELLC		(2)
>>> +
>>> +/*
>>> + * MOCS tables
>>> + *
>>> + * These are the MOCS tables that are programmed across all the rings.
>>> + * The control value is programmed to all the rings that support the
>>> + * MOCS registers. While the l3cc_values are only programmed to the
>>> + * LNCFCMOCS0 - LNCFCMOCS32 registers.
>>> + *
>>> + * NOTE: These tables MUST start with being uncached and the length MUST 
> be
>>> + *       less than 63 as the last two registers are reserved by the 
> hardware.
>>> + */
>>> +static struct drm_i915_mocs_entry skylake_mocs_table[] = {
>>> +	 /* {0x00000009, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_UC) | MOCS_TGT_CACHE(LLC_ELLC) |
>>> +		MOCS_LRUM(0) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x0000003b, 0x0030} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC_ELLC) |
>>> +		MOCS_LRUM(3) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_WB))},
>>> +	 /* {0x00000039, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_UC) | MOCS_TGT_CACHE(LLC_ELLC) |
>>> +		MOCS_LRUM(3) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x00000017, 0x0030} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(1) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_WB))},
>>> +	 /* {0x00000017, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(1) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x00000019, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_UC) | MOCS_TGT_CACHE(LLC_ELLC) |
>>> +		MOCS_LRUM(1) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x00000037, 0x0030} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(3) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_WB))},
>>> +	 /* {0x00000037, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(3) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x0000003b, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC_ELLC) |
>>> +		MOCS_LRUM(3) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +};
>>
>> Mesa will want an additional entry with TC=LLC/eLLC, LeCC=PTE, L3CC=WB,
>> everything else unset, I'll reply with a userspace patch making use of
>> your change if you add such an entry.
Ok. I think what you want is, same as entry two, but use the underlying
pagetable settings and not specify the EDRAM settings. Please confirm in 
the new patchset.
>>
>> Another thing worth mentioning is that entries 0, 2 and 5 seem to do the
>> same thing suspiciously, the only difference is the LRUM field which
>> AFAIK doesn't have any effect for LeCC=UC.  Is my understanding correct?
>>
> These tables are generated via requests and then boiled down to the above. 
> So some of the entries are by request. Swings and roundabouts, can remove 
> the ones that look redundant but then the tuning that has been done wont 
> match. I'll add the new entry at the end of the table.
>>> +
>>> +static struct drm_i915_mocs_entry broxton_mocs_table[] = {
>>> +	 /* {0x00000001, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_UC) | MOCS_TGT_CACHE(ELLC) |
>>> +		MOCS_LRUM(0) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x00000005, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_UC) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(0) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x00000005, 0x0030} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_UC) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(0) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_WB))},
>>> +	 /* {0x00000017, 0x0030} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(1) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_WB))},
>>> +	 /* {0x00000017, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(1) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x00000019, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_UC) | MOCS_TGT_CACHE(LLC_ELLC) |
>>> +		MOCS_LRUM(1) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x00000037, 0x0030} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(3) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_WB))},
>>> +	 /* {0x00000037, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC) |
>>> +		MOCS_LRUM(3) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +	 /* {0x0000003b, 0x0010} */
>>> +	{(MOCS_CACHEABILITY(EDRAM_WB) | MOCS_TGT_CACHE(LLC_ELLC) |
>>> +		MOCS_LRUM(3) | MOCS_AOM(0) | MOCS_LECC_ESC(0) | MOCS_SCC(0) |
>>> +		MOC_PFM(0) | MOCS_SCF(0)),
>>> +		(MOCS_ESC(0) | MOCS_SCC(0) | MOCS_L3_CACHEABILITY(L3_UC))},
>>> +};
>>> +
>>
>> Wouldn't it be a good idea to have BXT's entries match SKL's for a given
>> index?  The TC, LeCC and LRUM settings you do here arguably don't have
>> any effect on BXT, L3CC does but it doesn't match SKL's setting for
>> entries 1 and 2.  Is there any reason for this?
> As mentioned above this table is auto-generated and matches another tuned 
> table, simply keeping them the same allows for the tuning to be consistent 
> across platforms.
>
> Peter.
>>
>> Other than that looks good.
>>
>>> +/**
>>> + * get_mocs_settings
>>> + *
>>> + * This function will return the values of the MOCS table that needs to
>>> + * be programmed for the platform. It will return the values that need
>>> + * to be programmed and if they need to be programmed.
>>> + *
>>> + * If the return values is false then the registers do not need 
> programming.
>>> + */
>>> +static bool get_mocs_settings(struct drm_device *dev,
>>> +			      struct drm_i915_mocs_table *table) {
>>> +	bool	result = false;
>>> +
>>> +	if (IS_SKYLAKE(dev)) {
>>> +		table->size  = ARRAY_SIZE(skylake_mocs_table);
>>> +		table->table = skylake_mocs_table;
>>> +		result = true;
>>> +	} else if (IS_BROXTON(dev)) {
>>> +		table->size  = ARRAY_SIZE(broxton_mocs_table);
>>> +		table->table = broxton_mocs_table;
>>> +		result = true;
>>> +	} else {
>>> +		/* Platform that should have a MOCS table does not */
>>> +		WARN_ON(INTEL_INFO(dev)->gen >= 9);
>>> +	}
>>> +
>>> +	return result;
>>> +}
>>> +
>>> +/**
>>> + * emit_mocs_control_table() - emit the mocs control table
>>> + * @ringbuf:	DRM device.
>>> + * @table:	The values to program into the control regs.
>>> + * @reg_base:	The base for the Engine that needs to be programmed.
>>> + *
>>> + * This function simply emits a MI_LOAD_REGISTER_IMM command for the
>>> + * given table starting at the given address.
>>> + *
>>> + * Return: Nothing.
>>> + */
>>> +static void emit_mocs_control_table(struct intel_ringbuffer *ringbuf,
>>> +				    struct drm_i915_mocs_table *table,
>>> +				    u32 reg_base)
>>> +{
>>> +	unsigned int index;
>>> +
>>> +	intel_logical_ring_emit(ringbuf,
>>> +			MI_LOAD_REGISTER_IMM(GEN9_NUM_MOCS_ENTRIES));
>>> +
>>> +	for (index = 0; index < table->size; index++) {
>>> +		intel_logical_ring_emit(ringbuf, reg_base + (index * 4));
>>> +		intel_logical_ring_emit(ringbuf,
>>> +					table->table[index].control_value);
>>> +	}
>>> +
>>> +	/*
>>> +	 * Ok, now set the unused entries to uncached. These entries are
>>> +	 * officially undefined and no contact is given for the contents and
>>> +	 * settings is given for these entries.
>>> +	 *
>>> +	 * Entry 0 in the table is uncached - so we are just written that
>>> +	 * value to all the used entries.
>>> +	 */
>>> +	for (; index < GEN9_NUM_MOCS_ENTRIES; index++) {
>>> +		intel_logical_ring_emit(ringbuf, reg_base + (index * 4));
>>> +		intel_logical_ring_emit(ringbuf, 
> table->table[0].control_value);
>>> +	}
>>> +
>>> +	intel_logical_ring_emit(ringbuf, MI_NOOP);
>>> +}
>>> +
>>> +/**
>>> + * emit_mocs_l3cc_table() - emit the mocs control table
>>> + * @ringbuf:	DRM device.
>>> + * @table:	The values to program into the control regs.
>>> + *
>>> + * This function simply emits a MI_LOAD_REGISTER_IMM command for the
>>> + * given table starting at the given address. This register set is 
> programmed
>>> + * in pairs.
>>> + *
>>> + * Return: Nothing.
>>> + */
>>> +static void emit_mocs_l3cc_table(struct intel_ringbuffer *ringbuf,
>>> +			 struct drm_i915_mocs_table *table) {
>>> +	unsigned int count;
>>> +	unsigned int i;
>>> +	u32 value;
>>> +	u32 filler = (table->table[0].l3cc_value & 0xffff) |
>>> +			((table->table[0].l3cc_value & 0xffff) << 16);
>>> +
>>> +	intel_logical_ring_emit(ringbuf,
>>> +			MI_LOAD_REGISTER_IMM(GEN9_NUM_MOCS_ENTRIES / 2));
>>> +
>>> +	for (i = 0, count = 0; i < table->size / 2; i++, count += 2) {
>>> +		value = (table->table[count].l3cc_value & 0xffff) |
>>> +			((table->table[count + 1].l3cc_value & 0xffff) << 
> 16);
>>> +
>>> +		intel_logical_ring_emit(ringbuf, GEN9_LNCFCMOCS0 + (i * 4));
>>> +		intel_logical_ring_emit(ringbuf, value);
>>> +	}
>>> +
>>> +	if (table->size & 0x01) {
>>> +		/* Odd table size - 1 left over */
>>> +		value = (table->table[count].l3cc_value & 0xffff) |
>>> +			((table->table[0].l3cc_value & 0xffff) << 16);
>>> +	} else
>>> +		value = filler;
>>> +
>>> +	/*
>>> +	 * Now set the rest of the table to uncached - use entry 0 as this
>>> +	 * will be uncached. Leave the last pair as initialised as they are
>>> +	 * reserved by the hardware.
>>> +	 */
>>> +	for (; i < (GEN9_NUM_MOCS_ENTRIES / 2) - 1; i++) {
>>> +		intel_logical_ring_emit(ringbuf, GEN9_LNCFCMOCS0 + (i * 4));
>>> +		intel_logical_ring_emit(ringbuf, value);
>>> +
>>> +		value = filler;
>>> +	}
>>> +
>>> +	intel_logical_ring_emit(ringbuf, MI_NOOP);
>>> +}
>>> +
>>> +/*
>>> + * gen9_program_mocs() - program the MOCS register.
>>> + *
>>> + * ring:	The ring that the programming batch will be run in.
>>> + * ctx:		The intel_context to be used.
>>> + *
>>> + * This function will emit a batch buffer with the values required for
>>> + * programming the MOCS register values for all the currently supported
>>> + * rings.
>>> + *
>>> + * These registers are partially stored in the RCS context, so they are
>>> + * emitted at the same time so that when a context is created these 
> registers
>>> + * are set up. These registers have to be emitted into the start of the
>>> + * context as setting the ELSP will re-init some of these registers back
>>> + * to the hw values.
>>> + *
>>> + * Return: 0 on success, otherwise the error status.
>>> + */
>>> +int gen9_program_mocs(struct intel_engine_cs *ring,
>>> +			  struct intel_context *ctx)
>>> +{
>>> +	int ret = 0;
>>> +
>>> +	struct drm_i915_mocs_table t;
>>> +	struct drm_device *dev = ring->dev;
>>> +	struct intel_ringbuffer *ringbuf = ctx->engine[ring->id].ringbuf;
>>> +
>>> +	if (get_mocs_settings(dev, &t)) {
>>> +		u32 table_size;
>>> +
>>> +		/*
>>> +		 * OK. For each supported ring:
>>> +		 *  number of mocs entries * 2 dwords for each control_value
>>> +		 *  plus number of mocs entries /2 dwords for l3cc values.
>>> +		 *
>>> +		 *  Plus 1 for the load command and 1 for the NOOP per ring
>>> +		 *  and the l3cc programming.
>>> +		 */
>>> +		table_size = GEN9_NUM_MOCS_RINGS *
>>> +				((2 * GEN9_NUM_MOCS_ENTRIES) + 2) +
>>> +				GEN9_NUM_MOCS_ENTRIES + 2;
>>> +		ret = intel_logical_ring_begin(ringbuf, ctx, table_size);
>>> +		if (ret) {
>>> +			DRM_DEBUG("intel_logical_ring_begin failed %d\n", 
> ret);
>>> +			return ret;
>>> +		}
>>> +
>>> +		/* program the control registers */
>>> +		emit_mocs_control_table(ringbuf, &t, GEN9_GFX_MOCS_0);
>>> +		emit_mocs_control_table(ringbuf, &t, GEN9_MFX0_MOCS_0);
>>> +		emit_mocs_control_table(ringbuf, &t, GEN9_MFX1_MOCS_0);
>>> +		emit_mocs_control_table(ringbuf, &t, GEN9_VEBOX_MOCS_0);
>>> +		emit_mocs_control_table(ringbuf, &t, GEN9_BLT_MOCS_0);
>>> +
>>> +		/* now program the l3cc registers */
>>> +		emit_mocs_l3cc_table(ringbuf, &t);
>>> +
>>> +		intel_logical_ring_advance(ringbuf);
>>> +
>>> +		DRM_DEBUG("MOCS: Table set in Context\n");
>>> +	} else {
>>> +		DRM_DEBUG("MOCS: Table Not supported on platform\n");
>>> +	}
>>> +
>>> +	return ret;
>>> +}
>>> +
>>> diff --git a/drivers/gpu/drm/i915/intel_mocs.h 
> b/drivers/gpu/drm/i915/intel_mocs.h
>>> new file mode 100644
>>> index 0000000..e2780ce
>>> --- /dev/null
>>> +++ b/drivers/gpu/drm/i915/intel_mocs.h
>>> @@ -0,0 +1,64 @@
>>> +/*
>>> + * Copyright (c) 2015 Intel Corporation
>>> + *
>>> + * 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 (including the 
> next
>>> + * paragraph) 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 AUTHORS OR COPYRIGHT HOLDERS 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:
>>> + *    Peter Antoine <peter.antoine at intel.com>
>>> + */
>>> +
>>> +#ifndef INTEL_MOCS_H
>>> +#define INTEL_MOCS_H
>>> +
>>> +/**
>>> + * DOC: Memory Objects Control State (MOCS)
>>> + *
>>> + * Motivation:
>>> + * In previous Gens the MOCS settings was a value that was set by user 
> land as
>>> + * part of the batch. In Gen9 this has changed to be a single table (per 
> ring)
>>> + * that all batches now reference by index instead of programming the 
> MOCS
>>> + * directly.
>>> + *
>>> + * The one wrinkle in this is that only PART of the MOCS tables are 
> included
>>> + * in context (The GFX_MOCS_0 - GFX_MOCS_64 and the LNCFCMOCS0 - 
> LNCFCMOCS32
>>> + * registers). The rest are not (the settings for the other rings).
>>> + *
>>> + * This table needs to be set at system start-up because the way the 
> table
>>> + * interacts with the contexts and the GmmLib interface.
>>> + *
>>> + *
>>> + * Implementation:
>>> + *
>>> + * The table is programmed on a platform basis from a table that is 
> generated
>>> + * from the one that has been agreed by the different responsible 
> parties. This
>>> + * tables (one per supported platform) is defined in intel_mocs.c and is
>>> + * programmed in the first batch after the context is loaded (with the 
> hardware
>>> + * workarounds). This will then let the usual context handling keep the 
> MOCS in
>>> + * step.
>>> + */
>>> +
>>> +#include <drm/drmP.h>
>>> +#include "i915_drv.h"
>>> +
>>> +int gen9_program_mocs(struct intel_engine_cs *ring,
>>> +			struct intel_context *ctx);
>>> +
>>> +#endif
>>> +
>>> --
>>> 1.9.1
>>>
>>> _______________________________________________
>>> Intel-gfx mailing list
>>> Intel-gfx at lists.freedesktop.org
>>> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>>
>
> --
>    Peter Antoine (Android Graphics Driver Software Engineer)
>    ---------------------------------------------------------------------
>    Intel Corporation (UK) Limited
>    Registered No. 1134945 (England)
>    Registered Office: Pipers Way, Swindon SN3 1RJ
>    VAT No: 860 2173 47
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>

--
    Peter Antoine (Android Graphics Driver Software Engineer)
    ---------------------------------------------------------------------
    Intel Corporation (UK) Limited
    Registered No. 1134945 (England)
    Registered Office: Pipers Way, Swindon SN3 1RJ
    VAT No: 860 2173 47


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