linuxdebug/drivers/gpu/drm/i915/gt/intel_gt_mcr.c

523 lines
16 KiB
C

// SPDX-License-Identifier: MIT
/*
* Copyright © 2022 Intel Corporation
*/
#include "i915_drv.h"
#include "intel_gt_mcr.h"
#include "intel_gt_regs.h"
/**
* DOC: GT Multicast/Replicated (MCR) Register Support
*
* Some GT registers are designed as "multicast" or "replicated" registers:
* multiple instances of the same register share a single MMIO offset. MCR
* registers are generally used when the hardware needs to potentially track
* independent values of a register per hardware unit (e.g., per-subslice,
* per-L3bank, etc.). The specific types of replication that exist vary
* per-platform.
*
* MMIO accesses to MCR registers are controlled according to the settings
* programmed in the platform's MCR_SELECTOR register(s). MMIO writes to MCR
* registers can be done in either a (i.e., a single write updates all
* instances of the register to the same value) or unicast (a write updates only
* one specific instance). Reads of MCR registers always operate in a unicast
* manner regardless of how the multicast/unicast bit is set in MCR_SELECTOR.
* Selection of a specific MCR instance for unicast operations is referred to
* as "steering."
*
* If MCR register operations are steered toward a hardware unit that is
* fused off or currently powered down due to power gating, the MMIO operation
* is "terminated" by the hardware. Terminated read operations will return a
* value of zero and terminated unicast write operations will be silently
* ignored.
*/
#define HAS_MSLICE_STEERING(dev_priv) (INTEL_INFO(dev_priv)->has_mslice_steering)
static const char * const intel_steering_types[] = {
"L3BANK",
"MSLICE",
"LNCF",
"INSTANCE 0",
};
static const struct intel_mmio_range icl_l3bank_steering_table[] = {
{ 0x00B100, 0x00B3FF },
{},
};
static const struct intel_mmio_range xehpsdv_mslice_steering_table[] = {
{ 0x004000, 0x004AFF },
{ 0x00C800, 0x00CFFF },
{ 0x00DD00, 0x00DDFF },
{ 0x00E900, 0x00FFFF }, /* 0xEA00 - OxEFFF is unused */
{},
};
static const struct intel_mmio_range xehpsdv_lncf_steering_table[] = {
{ 0x00B000, 0x00B0FF },
{ 0x00D800, 0x00D8FF },
{},
};
static const struct intel_mmio_range dg2_lncf_steering_table[] = {
{ 0x00B000, 0x00B0FF },
{ 0x00D880, 0x00D8FF },
{},
};
/*
* We have several types of MCR registers on PVC where steering to (0,0)
* will always provide us with a non-terminated value. We'll stick them
* all in the same table for simplicity.
*/
static const struct intel_mmio_range pvc_instance0_steering_table[] = {
{ 0x004000, 0x004AFF }, /* HALF-BSLICE */
{ 0x008800, 0x00887F }, /* CC */
{ 0x008A80, 0x008AFF }, /* TILEPSMI */
{ 0x00B000, 0x00B0FF }, /* HALF-BSLICE */
{ 0x00B100, 0x00B3FF }, /* L3BANK */
{ 0x00C800, 0x00CFFF }, /* HALF-BSLICE */
{ 0x00D800, 0x00D8FF }, /* HALF-BSLICE */
{ 0x00DD00, 0x00DDFF }, /* BSLICE */
{ 0x00E900, 0x00E9FF }, /* HALF-BSLICE */
{ 0x00EC00, 0x00EEFF }, /* HALF-BSLICE */
{ 0x00F000, 0x00FFFF }, /* HALF-BSLICE */
{ 0x024180, 0x0241FF }, /* HALF-BSLICE */
{},
};
void intel_gt_mcr_init(struct intel_gt *gt)
{
struct drm_i915_private *i915 = gt->i915;
/*
* An mslice is unavailable only if both the meml3 for the slice is
* disabled *and* all of the DSS in the slice (quadrant) are disabled.
*/
if (HAS_MSLICE_STEERING(i915)) {
gt->info.mslice_mask =
intel_slicemask_from_xehp_dssmask(gt->info.sseu.subslice_mask,
GEN_DSS_PER_MSLICE);
gt->info.mslice_mask |=
(intel_uncore_read(gt->uncore, GEN10_MIRROR_FUSE3) &
GEN12_MEML3_EN_MASK);
if (!gt->info.mslice_mask) /* should be impossible! */
drm_warn(&i915->drm, "mslice mask all zero!\n");
}
if (IS_PONTEVECCHIO(i915)) {
gt->steering_table[INSTANCE0] = pvc_instance0_steering_table;
} else if (IS_DG2(i915)) {
gt->steering_table[MSLICE] = xehpsdv_mslice_steering_table;
gt->steering_table[LNCF] = dg2_lncf_steering_table;
} else if (IS_XEHPSDV(i915)) {
gt->steering_table[MSLICE] = xehpsdv_mslice_steering_table;
gt->steering_table[LNCF] = xehpsdv_lncf_steering_table;
} else if (GRAPHICS_VER(i915) >= 11 &&
GRAPHICS_VER_FULL(i915) < IP_VER(12, 50)) {
gt->steering_table[L3BANK] = icl_l3bank_steering_table;
gt->info.l3bank_mask =
~intel_uncore_read(gt->uncore, GEN10_MIRROR_FUSE3) &
GEN10_L3BANK_MASK;
if (!gt->info.l3bank_mask) /* should be impossible! */
drm_warn(&i915->drm, "L3 bank mask is all zero!\n");
} else if (GRAPHICS_VER(i915) >= 11) {
/*
* We expect all modern platforms to have at least some
* type of steering that needs to be initialized.
*/
MISSING_CASE(INTEL_INFO(i915)->platform);
}
}
/*
* rw_with_mcr_steering_fw - Access a register with specific MCR steering
* @uncore: pointer to struct intel_uncore
* @reg: register being accessed
* @rw_flag: FW_REG_READ for read access or FW_REG_WRITE for write access
* @group: group number (documented as "sliceid" on older platforms)
* @instance: instance number (documented as "subsliceid" on older platforms)
* @value: register value to be written (ignored for read)
*
* Return: 0 for write access. register value for read access.
*
* Caller needs to make sure the relevant forcewake wells are up.
*/
static u32 rw_with_mcr_steering_fw(struct intel_uncore *uncore,
i915_reg_t reg, u8 rw_flag,
int group, int instance, u32 value)
{
u32 mcr_mask, mcr_ss, mcr, old_mcr, val = 0;
lockdep_assert_held(&uncore->lock);
if (GRAPHICS_VER(uncore->i915) >= 11) {
mcr_mask = GEN11_MCR_SLICE_MASK | GEN11_MCR_SUBSLICE_MASK;
mcr_ss = GEN11_MCR_SLICE(group) | GEN11_MCR_SUBSLICE(instance);
/*
* Wa_22013088509
*
* The setting of the multicast/unicast bit usually wouldn't
* matter for read operations (which always return the value
* from a single register instance regardless of how that bit
* is set), but some platforms have a workaround requiring us
* to remain in multicast mode for reads. There's no real
* downside to this, so we'll just go ahead and do so on all
* platforms; we'll only clear the multicast bit from the mask
* when exlicitly doing a write operation.
*/
if (rw_flag == FW_REG_WRITE)
mcr_mask |= GEN11_MCR_MULTICAST;
} else {
mcr_mask = GEN8_MCR_SLICE_MASK | GEN8_MCR_SUBSLICE_MASK;
mcr_ss = GEN8_MCR_SLICE(group) | GEN8_MCR_SUBSLICE(instance);
}
old_mcr = mcr = intel_uncore_read_fw(uncore, GEN8_MCR_SELECTOR);
mcr &= ~mcr_mask;
mcr |= mcr_ss;
intel_uncore_write_fw(uncore, GEN8_MCR_SELECTOR, mcr);
if (rw_flag == FW_REG_READ)
val = intel_uncore_read_fw(uncore, reg);
else
intel_uncore_write_fw(uncore, reg, value);
mcr &= ~mcr_mask;
mcr |= old_mcr & mcr_mask;
intel_uncore_write_fw(uncore, GEN8_MCR_SELECTOR, mcr);
return val;
}
static u32 rw_with_mcr_steering(struct intel_uncore *uncore,
i915_reg_t reg, u8 rw_flag,
int group, int instance,
u32 value)
{
enum forcewake_domains fw_domains;
u32 val;
fw_domains = intel_uncore_forcewake_for_reg(uncore, reg,
rw_flag);
fw_domains |= intel_uncore_forcewake_for_reg(uncore,
GEN8_MCR_SELECTOR,
FW_REG_READ | FW_REG_WRITE);
spin_lock_irq(&uncore->lock);
intel_uncore_forcewake_get__locked(uncore, fw_domains);
val = rw_with_mcr_steering_fw(uncore, reg, rw_flag, group, instance, value);
intel_uncore_forcewake_put__locked(uncore, fw_domains);
spin_unlock_irq(&uncore->lock);
return val;
}
/**
* intel_gt_mcr_read - read a specific instance of an MCR register
* @gt: GT structure
* @reg: the MCR register to read
* @group: the MCR group
* @instance: the MCR instance
*
* Returns the value read from an MCR register after steering toward a specific
* group/instance.
*/
u32 intel_gt_mcr_read(struct intel_gt *gt,
i915_reg_t reg,
int group, int instance)
{
return rw_with_mcr_steering(gt->uncore, reg, FW_REG_READ, group, instance, 0);
}
/**
* intel_gt_mcr_unicast_write - write a specific instance of an MCR register
* @gt: GT structure
* @reg: the MCR register to write
* @value: value to write
* @group: the MCR group
* @instance: the MCR instance
*
* Write an MCR register in unicast mode after steering toward a specific
* group/instance.
*/
void intel_gt_mcr_unicast_write(struct intel_gt *gt, i915_reg_t reg, u32 value,
int group, int instance)
{
rw_with_mcr_steering(gt->uncore, reg, FW_REG_WRITE, group, instance, value);
}
/**
* intel_gt_mcr_multicast_write - write a value to all instances of an MCR register
* @gt: GT structure
* @reg: the MCR register to write
* @value: value to write
*
* Write an MCR register in multicast mode to update all instances.
*/
void intel_gt_mcr_multicast_write(struct intel_gt *gt,
i915_reg_t reg, u32 value)
{
intel_uncore_write(gt->uncore, reg, value);
}
/**
* intel_gt_mcr_multicast_write_fw - write a value to all instances of an MCR register
* @gt: GT structure
* @reg: the MCR register to write
* @value: value to write
*
* Write an MCR register in multicast mode to update all instances. This
* function assumes the caller is already holding any necessary forcewake
* domains; use intel_gt_mcr_multicast_write() in cases where forcewake should
* be obtained automatically.
*/
void intel_gt_mcr_multicast_write_fw(struct intel_gt *gt, i915_reg_t reg, u32 value)
{
intel_uncore_write_fw(gt->uncore, reg, value);
}
/*
* reg_needs_read_steering - determine whether a register read requires
* explicit steering
* @gt: GT structure
* @reg: the register to check steering requirements for
* @type: type of multicast steering to check
*
* Determines whether @reg needs explicit steering of a specific type for
* reads.
*
* Returns false if @reg does not belong to a register range of the given
* steering type, or if the default (subslice-based) steering IDs are suitable
* for @type steering too.
*/
static bool reg_needs_read_steering(struct intel_gt *gt,
i915_reg_t reg,
enum intel_steering_type type)
{
const u32 offset = i915_mmio_reg_offset(reg);
const struct intel_mmio_range *entry;
if (likely(!gt->steering_table[type]))
return false;
for (entry = gt->steering_table[type]; entry->end; entry++) {
if (offset >= entry->start && offset <= entry->end)
return true;
}
return false;
}
/*
* get_nonterminated_steering - determines valid IDs for a class of MCR steering
* @gt: GT structure
* @type: multicast register type
* @group: Group ID returned
* @instance: Instance ID returned
*
* Determines group and instance values that will steer reads of the specified
* MCR class to a non-terminated instance.
*/
static void get_nonterminated_steering(struct intel_gt *gt,
enum intel_steering_type type,
u8 *group, u8 *instance)
{
switch (type) {
case L3BANK:
*group = 0; /* unused */
*instance = __ffs(gt->info.l3bank_mask);
break;
case MSLICE:
GEM_WARN_ON(!HAS_MSLICE_STEERING(gt->i915));
*group = __ffs(gt->info.mslice_mask);
*instance = 0; /* unused */
break;
case LNCF:
/*
* An LNCF is always present if its mslice is present, so we
* can safely just steer to LNCF 0 in all cases.
*/
GEM_WARN_ON(!HAS_MSLICE_STEERING(gt->i915));
*group = __ffs(gt->info.mslice_mask) << 1;
*instance = 0; /* unused */
break;
case INSTANCE0:
/*
* There are a lot of MCR types for which instance (0, 0)
* will always provide a non-terminated value.
*/
*group = 0;
*instance = 0;
break;
default:
MISSING_CASE(type);
*group = 0;
*instance = 0;
}
}
/**
* intel_gt_mcr_get_nonterminated_steering - find group/instance values that
* will steer a register to a non-terminated instance
* @gt: GT structure
* @reg: register for which the steering is required
* @group: return variable for group steering
* @instance: return variable for instance steering
*
* This function returns a group/instance pair that is guaranteed to work for
* read steering of the given register. Note that a value will be returned even
* if the register is not replicated and therefore does not actually require
* steering.
*/
void intel_gt_mcr_get_nonterminated_steering(struct intel_gt *gt,
i915_reg_t reg,
u8 *group, u8 *instance)
{
int type;
for (type = 0; type < NUM_STEERING_TYPES; type++) {
if (reg_needs_read_steering(gt, reg, type)) {
get_nonterminated_steering(gt, type, group, instance);
return;
}
}
*group = gt->default_steering.groupid;
*instance = gt->default_steering.instanceid;
}
/**
* intel_gt_mcr_read_any_fw - reads one instance of an MCR register
* @gt: GT structure
* @reg: register to read
*
* Reads a GT MCR register. The read will be steered to a non-terminated
* instance (i.e., one that isn't fused off or powered down by power gating).
* This function assumes the caller is already holding any necessary forcewake
* domains; use intel_gt_mcr_read_any() in cases where forcewake should be
* obtained automatically.
*
* Returns the value from a non-terminated instance of @reg.
*/
u32 intel_gt_mcr_read_any_fw(struct intel_gt *gt, i915_reg_t reg)
{
int type;
u8 group, instance;
for (type = 0; type < NUM_STEERING_TYPES; type++) {
if (reg_needs_read_steering(gt, reg, type)) {
get_nonterminated_steering(gt, type, &group, &instance);
return rw_with_mcr_steering_fw(gt->uncore, reg,
FW_REG_READ,
group, instance, 0);
}
}
return intel_uncore_read_fw(gt->uncore, reg);
}
/**
* intel_gt_mcr_read_any - reads one instance of an MCR register
* @gt: GT structure
* @reg: register to read
*
* Reads a GT MCR register. The read will be steered to a non-terminated
* instance (i.e., one that isn't fused off or powered down by power gating).
*
* Returns the value from a non-terminated instance of @reg.
*/
u32 intel_gt_mcr_read_any(struct intel_gt *gt, i915_reg_t reg)
{
int type;
u8 group, instance;
for (type = 0; type < NUM_STEERING_TYPES; type++) {
if (reg_needs_read_steering(gt, reg, type)) {
get_nonterminated_steering(gt, type, &group, &instance);
return rw_with_mcr_steering(gt->uncore, reg,
FW_REG_READ,
group, instance, 0);
}
}
return intel_uncore_read(gt->uncore, reg);
}
static void report_steering_type(struct drm_printer *p,
struct intel_gt *gt,
enum intel_steering_type type,
bool dump_table)
{
const struct intel_mmio_range *entry;
u8 group, instance;
BUILD_BUG_ON(ARRAY_SIZE(intel_steering_types) != NUM_STEERING_TYPES);
if (!gt->steering_table[type]) {
drm_printf(p, "%s steering: uses default steering\n",
intel_steering_types[type]);
return;
}
get_nonterminated_steering(gt, type, &group, &instance);
drm_printf(p, "%s steering: group=0x%x, instance=0x%x\n",
intel_steering_types[type], group, instance);
if (!dump_table)
return;
for (entry = gt->steering_table[type]; entry->end; entry++)
drm_printf(p, "\t0x%06x - 0x%06x\n", entry->start, entry->end);
}
void intel_gt_mcr_report_steering(struct drm_printer *p, struct intel_gt *gt,
bool dump_table)
{
drm_printf(p, "Default steering: group=0x%x, instance=0x%x\n",
gt->default_steering.groupid,
gt->default_steering.instanceid);
if (IS_PONTEVECCHIO(gt->i915)) {
report_steering_type(p, gt, INSTANCE0, dump_table);
} else if (HAS_MSLICE_STEERING(gt->i915)) {
report_steering_type(p, gt, MSLICE, dump_table);
report_steering_type(p, gt, LNCF, dump_table);
}
}
/**
* intel_gt_mcr_get_ss_steering - returns the group/instance steering for a SS
* @gt: GT structure
* @dss: DSS ID to obtain steering for
* @group: pointer to storage for steering group ID
* @instance: pointer to storage for steering instance ID
*
* Returns the steering IDs (via the @group and @instance parameters) that
* correspond to a specific subslice/DSS ID.
*/
void intel_gt_mcr_get_ss_steering(struct intel_gt *gt, unsigned int dss,
unsigned int *group, unsigned int *instance)
{
if (IS_PONTEVECCHIO(gt->i915)) {
*group = dss / GEN_DSS_PER_CSLICE;
*instance = dss % GEN_DSS_PER_CSLICE;
} else if (GRAPHICS_VER_FULL(gt->i915) >= IP_VER(12, 50)) {
*group = dss / GEN_DSS_PER_GSLICE;
*instance = dss % GEN_DSS_PER_GSLICE;
} else {
*group = dss / GEN_MAX_SS_PER_HSW_SLICE;
*instance = dss % GEN_MAX_SS_PER_HSW_SLICE;
return;
}
}