From 061489c65ff57ee9f757d7a519fb9a09e5fbadd6 Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Mon, 23 Sep 2019 10:09:23 +0300 Subject: drm/i915/dsb: single register write function for DSB. DSB support single register write through opcode 0x1. Generic api created which accumulate all single register write in a batch buffer and once DSB is triggered, it will program all the registers at the same time. v1: Initial version. v2: Unused macro removed and cosmetic changes done. (Shashank) v3: set free_pos to zero in dsb-put() instead dsb-get() and a cosmetic change. (Shashank) v4: macro of indexed-write is moved. (Shashank) Cc: Jani Nikula Cc: Rodrigo Vivi Cc: Shashank Sharma Reviewed-by: Shashank Sharma Signed-off-by: Animesh Manna Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20190920115930.27829-4-animesh.manna@intel.com --- drivers/gpu/drm/i915/display/intel_dsb.c | 29 +++++++++++++++++++++++++++++ drivers/gpu/drm/i915/display/intel_dsb.h | 9 +++++++++ 2 files changed, 38 insertions(+) (limited to 'drivers') diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c index 2ed277670f15..f94cd6dc98b6 100644 --- a/drivers/gpu/drm/i915/display/intel_dsb.c +++ b/drivers/gpu/drm/i915/display/intel_dsb.c @@ -9,6 +9,12 @@ #define DSB_BUF_SIZE (2 * PAGE_SIZE) +/* DSB opcodes. */ +#define DSB_OPCODE_SHIFT 24 +#define DSB_OPCODE_MMIO_WRITE 0x1 +#define DSB_BYTE_EN 0xF +#define DSB_BYTE_EN_SHIFT 20 + struct intel_dsb * intel_dsb_get(struct intel_crtc *crtc) { @@ -76,5 +82,28 @@ void intel_dsb_put(struct intel_dsb *dsb) i915_vma_unpin_and_release(&dsb->vma, 0); mutex_unlock(&i915->drm.struct_mutex); dsb->cmd_buf = NULL; + dsb->free_pos = 0; + } +} + +void intel_dsb_reg_write(struct intel_dsb *dsb, i915_reg_t reg, u32 val) +{ + struct intel_crtc *crtc = container_of(dsb, typeof(*crtc), dsb); + struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); + u32 *buf = dsb->cmd_buf; + + if (!buf) { + I915_WRITE(reg, val); + return; + } + + if (WARN_ON(dsb->free_pos >= DSB_BUF_SIZE)) { + DRM_DEBUG_KMS("DSB buffer overflow\n"); + return; } + + buf[dsb->free_pos++] = val; + buf[dsb->free_pos++] = (DSB_OPCODE_MMIO_WRITE << DSB_OPCODE_SHIFT) | + (DSB_BYTE_EN << DSB_BYTE_EN_SHIFT) | + i915_mmio_reg_offset(reg); } diff --git a/drivers/gpu/drm/i915/display/intel_dsb.h b/drivers/gpu/drm/i915/display/intel_dsb.h index b8639864df50..839cbf621fa2 100644 --- a/drivers/gpu/drm/i915/display/intel_dsb.h +++ b/drivers/gpu/drm/i915/display/intel_dsb.h @@ -8,6 +8,8 @@ #include +#include "i915_reg.h" + struct intel_crtc; struct i915_vma; @@ -24,10 +26,17 @@ struct intel_dsb { enum dsb_id id; u32 *cmd_buf; struct i915_vma *vma; + + /* + * free_pos will point the first free entry position + * and help in calculating tail of command buffer. + */ + int free_pos; }; struct intel_dsb * intel_dsb_get(struct intel_crtc *crtc); void intel_dsb_put(struct intel_dsb *dsb); +void intel_dsb_reg_write(struct intel_dsb *dsb, i915_reg_t reg, u32 val); #endif -- cgit v1.2.3