diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gt/intel_gt_mcr.c')
-rw-r--r-- | drivers/gpu/drm/i915/gt/intel_gt_mcr.c | 497 |
1 files changed, 497 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_mcr.c b/drivers/gpu/drm/i915/gt/intel_gt_mcr.c new file mode 100644 index 000000000000..777025d5bd66 --- /dev/null +++ b/drivers/gpu/drm/i915/gt/intel_gt_mcr.c @@ -0,0 +1,497 @@ +// 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); + } +} + |