| Message ID | 20230329-rfc-msm-dsc-helper-v3-1-6bec0d277a83@quicinc.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Introduce MSM-specific DSC helpers | expand |
On 4/4/2023 4:56 PM, Jessica Zhang wrote: > Introduce MSM-specific DSC helper methods, as some calculations are > common between DP and DSC. > > Changes in v2: > - Moved files up to msm/ directory > - Dropped get_comp_ratio() helper > - Used drm_int2fixp() to convert to integers to fp > - Style changes to improve readability > - Dropped unused bpp variable in msm_dsc_get_dce_bytes_per_line() > - Changed msm_dsc_get_slice_per_intf() to a static inline method > - Dropped last division step of msm_dsc_get_pclk_per_line() and changed > method name accordingly > - Changed DSC_BPP macro to drm_dsc_get_bpp_int() helper method > - Fixed some math issues caused by passing in incorrect types to > drm_fixed methods in get_bytes_per_soft_slice() > > Changes in v3: > - Dropped src_bpp parameter from all methods -- src_bpp can be > calculated as dsc->bits_per_component * 3 > - Dropped intf_width parameter from get_bytes_per_soft_slice() > - Moved dsc->bits_per_component to numerator calculation in > get_bytes_per_soft_slice() > - Renamed msm_dsc_get_uncompressed_pclk_per_line to > *_get_uncompressed_pclk_per_intf() > - Removed dsc->slice_width check from > msm_dsc_get_uncompressed_pclk_per_intf() > - Made get_bytes_per_soft_slice() a public method (this will be called > later to help calculate DP pclk params) > - Added documentation in comments > - Moved extra_eol_bytes math out of msm_dsc_get_eol_byte_num() and > renamed msm_dsc_get_eol_byte_num to *_get_bytes_per_intf. > > Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com> > --- > drivers/gpu/drm/msm/Makefile | 1 + > drivers/gpu/drm/msm/msm_dsc_helper.c | 47 ++++++++++++++++++++++++ > drivers/gpu/drm/msm/msm_dsc_helper.h | 70 ++++++++++++++++++++++++++++++++++++ > 3 files changed, 118 insertions(+) > > diff --git a/drivers/gpu/drm/msm/Makefile b/drivers/gpu/drm/msm/Makefile > index 7274c41228ed..b814fc80e2d5 100644 > --- a/drivers/gpu/drm/msm/Makefile > +++ b/drivers/gpu/drm/msm/Makefile > @@ -94,6 +94,7 @@ msm-y += \ > msm_atomic_tracepoints.o \ > msm_debugfs.o \ > msm_drv.o \ > + msm_dsc_helper.o \ > msm_fb.o \ > msm_fence.o \ > msm_gem.o \ > diff --git a/drivers/gpu/drm/msm/msm_dsc_helper.c b/drivers/gpu/drm/msm/msm_dsc_helper.c > new file mode 100644 > index 000000000000..c8c530211f50 > --- /dev/null > +++ b/drivers/gpu/drm/msm/msm_dsc_helper.c > @@ -0,0 +1,47 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved > + */ > + > +#include <linux/kernel.h> > +#include <linux/errno.h> > +#include <drm/drm_fixed.h> > + > +#include "msm_drv.h" > +#include "msm_dsc_helper.h" > + > +s64 get_bytes_per_soft_slice(struct drm_dsc_config *dsc) > +{ > + int bpp = msm_dsc_get_bpp_int(dsc); > + s64 numerator_fp, denominator_fp; > + s64 comp_ratio_fp = drm_fixp_from_fraction(dsc->bits_per_component * 3, bpp); > + > + numerator_fp = drm_int2fixp(dsc->slice_width * 3 * dsc->bits_per_component); > + denominator_fp = drm_fixp_mul(comp_ratio_fp, drm_int2fixp(8)); > + > + return drm_fixp_div(numerator_fp, denominator_fp); > +} > + > +u32 msm_dsc_get_bytes_per_intf(struct drm_dsc_config *dsc, int intf_width) > +{ > + u32 bytes_per_soft_slice, bytes_per_intf; > + s64 bytes_per_soft_slice_fp; > + int slice_per_intf = msm_dsc_get_slice_per_intf(dsc, intf_width); > + > + bytes_per_soft_slice_fp = get_bytes_per_soft_slice(dsc); > + bytes_per_soft_slice = drm_fixp2int_ceil(bytes_per_soft_slice_fp); > + > + bytes_per_intf = bytes_per_soft_slice * slice_per_intf; > + > + return bytes_per_intf; > +} > + > +int msm_dsc_get_uncompressed_pclk_per_intf(struct drm_dsc_config *dsc) > +{ > + s64 data_width; > + > + data_width = drm_fixp_mul(drm_int2fixp(dsc->slice_count), > + get_bytes_per_soft_slice(dsc)); > + > + return drm_fixp2int_ceil(data_width); > +} This is not really uncompressed pclk_per_intf. This is still calculated using the compression ratio so it is still compressed. I would suggest changing this to msm_dsc_get_pclk_per_intf(). Lets keep it simple. > diff --git a/drivers/gpu/drm/msm/msm_dsc_helper.h b/drivers/gpu/drm/msm/msm_dsc_helper.h > new file mode 100644 > index 000000000000..5ee972eb247c > --- /dev/null > +++ b/drivers/gpu/drm/msm/msm_dsc_helper.h > @@ -0,0 +1,70 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved > + */ > + > +#ifndef MSM_DSC_HELPER_H_ > +#define MSM_DSC_HELPER_H_ > + > +#include <drm/display/drm_dsc_helper.h> > +#include <drm/drm_modes.h> > + > +/* > + * Helper methods for MSM specific DSC calculations that are common between timing engine, > + * DSI, and DP. > + */ > + > +/** > + * msm_dsc_get_bpp_int - get bits per pixel integer value > + * @dsc: Pointer to drm dsc config struct > + */ > +static inline int msm_dsc_get_bpp_int(struct drm_dsc_config *dsc) > +{ > + WARN_ON_ONCE(dsc->bits_per_pixel & 0xf); > + return dsc->bits_per_pixel >> 4; > +} > + > +/** > + * msm_dsc_get_slice_per_intf - get number of slices per interface > + * @dsc: Pointer to drm dsc config struct > + * @intf_width: interface width > + */ > +static inline int msm_dsc_get_slice_per_intf(struct drm_dsc_config *dsc, int intf_width) > +{ > + return DIV_ROUND_UP(intf_width, dsc->slice_width); > +} > + > +/** > + * msm_dsc_get_dce_bytes_per_line - get bytes per line to help calculate data width > + * when configuring the timing engine > + * @dsc: Pointer to drm dsc config struct > + * @intf_width: interface width > + */ > +static inline u32 msm_dsc_get_dce_bytes_per_line(struct drm_dsc_config *dsc, int intf_width) > +{ > + return DIV_ROUND_UP(msm_dsc_get_bpp_int(dsc) * intf_width, 8); > +} > + > +/** > + * get_bytes_per_soft_slice - get size of each soft slice for dsc > + * @dsc: Pointer to drm dsc config struct > + */ > +s64 get_bytes_per_soft_slice(struct drm_dsc_config *dsc); > + > +/** > + * msm_dsc_get_bytes_per_intf - get total bytes per interface > + * @dsc: Pointer to drm dsc config struct > + * @intf_width: interface width > + */ > +u32 msm_dsc_get_bytes_per_intf(struct drm_dsc_config *dsc, int intf_width); > + > +/** > + * msm_dsc_get_uncompressed_pclk_per_intf - Calculate uncompressed pclk per line. > + * @dsc: Pointer to drm dsc config struct > + * > + * Note: This value will then be passed along to DSI and DP to calculate pclk_per_intf. > + * This is because DSI and DP divide the uncompressed pclk_per_intf by different > + * values depending on if widebus is enabled. > + */ > +int msm_dsc_get_uncompressed_pclk_per_intf(struct drm_dsc_config *dsc); > +#endif /* MSM_DSC_HELPER_H_ */ >
diff --git a/drivers/gpu/drm/msm/Makefile b/drivers/gpu/drm/msm/Makefile index 7274c41228ed..b814fc80e2d5 100644 --- a/drivers/gpu/drm/msm/Makefile +++ b/drivers/gpu/drm/msm/Makefile @@ -94,6 +94,7 @@ msm-y += \ msm_atomic_tracepoints.o \ msm_debugfs.o \ msm_drv.o \ + msm_dsc_helper.o \ msm_fb.o \ msm_fence.o \ msm_gem.o \ diff --git a/drivers/gpu/drm/msm/msm_dsc_helper.c b/drivers/gpu/drm/msm/msm_dsc_helper.c new file mode 100644 index 000000000000..c8c530211f50 --- /dev/null +++ b/drivers/gpu/drm/msm/msm_dsc_helper.c @@ -0,0 +1,47 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <drm/drm_fixed.h> + +#include "msm_drv.h" +#include "msm_dsc_helper.h" + +s64 get_bytes_per_soft_slice(struct drm_dsc_config *dsc) +{ + int bpp = msm_dsc_get_bpp_int(dsc); + s64 numerator_fp, denominator_fp; + s64 comp_ratio_fp = drm_fixp_from_fraction(dsc->bits_per_component * 3, bpp); + + numerator_fp = drm_int2fixp(dsc->slice_width * 3 * dsc->bits_per_component); + denominator_fp = drm_fixp_mul(comp_ratio_fp, drm_int2fixp(8)); + + return drm_fixp_div(numerator_fp, denominator_fp); +} + +u32 msm_dsc_get_bytes_per_intf(struct drm_dsc_config *dsc, int intf_width) +{ + u32 bytes_per_soft_slice, bytes_per_intf; + s64 bytes_per_soft_slice_fp; + int slice_per_intf = msm_dsc_get_slice_per_intf(dsc, intf_width); + + bytes_per_soft_slice_fp = get_bytes_per_soft_slice(dsc); + bytes_per_soft_slice = drm_fixp2int_ceil(bytes_per_soft_slice_fp); + + bytes_per_intf = bytes_per_soft_slice * slice_per_intf; + + return bytes_per_intf; +} + +int msm_dsc_get_uncompressed_pclk_per_intf(struct drm_dsc_config *dsc) +{ + s64 data_width; + + data_width = drm_fixp_mul(drm_int2fixp(dsc->slice_count), + get_bytes_per_soft_slice(dsc)); + + return drm_fixp2int_ceil(data_width); +} diff --git a/drivers/gpu/drm/msm/msm_dsc_helper.h b/drivers/gpu/drm/msm/msm_dsc_helper.h new file mode 100644 index 000000000000..5ee972eb247c --- /dev/null +++ b/drivers/gpu/drm/msm/msm_dsc_helper.h @@ -0,0 +1,70 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved + */ + +#ifndef MSM_DSC_HELPER_H_ +#define MSM_DSC_HELPER_H_ + +#include <drm/display/drm_dsc_helper.h> +#include <drm/drm_modes.h> + +/* + * Helper methods for MSM specific DSC calculations that are common between timing engine, + * DSI, and DP. + */ + +/** + * msm_dsc_get_bpp_int - get bits per pixel integer value + * @dsc: Pointer to drm dsc config struct + */ +static inline int msm_dsc_get_bpp_int(struct drm_dsc_config *dsc) +{ + WARN_ON_ONCE(dsc->bits_per_pixel & 0xf); + return dsc->bits_per_pixel >> 4; +} + +/** + * msm_dsc_get_slice_per_intf - get number of slices per interface + * @dsc: Pointer to drm dsc config struct + * @intf_width: interface width + */ +static inline int msm_dsc_get_slice_per_intf(struct drm_dsc_config *dsc, int intf_width) +{ + return DIV_ROUND_UP(intf_width, dsc->slice_width); +} + +/** + * msm_dsc_get_dce_bytes_per_line - get bytes per line to help calculate data width + * when configuring the timing engine + * @dsc: Pointer to drm dsc config struct + * @intf_width: interface width + */ +static inline u32 msm_dsc_get_dce_bytes_per_line(struct drm_dsc_config *dsc, int intf_width) +{ + return DIV_ROUND_UP(msm_dsc_get_bpp_int(dsc) * intf_width, 8); +} + +/** + * get_bytes_per_soft_slice - get size of each soft slice for dsc + * @dsc: Pointer to drm dsc config struct + */ +s64 get_bytes_per_soft_slice(struct drm_dsc_config *dsc); + +/** + * msm_dsc_get_bytes_per_intf - get total bytes per interface + * @dsc: Pointer to drm dsc config struct + * @intf_width: interface width + */ +u32 msm_dsc_get_bytes_per_intf(struct drm_dsc_config *dsc, int intf_width); + +/** + * msm_dsc_get_uncompressed_pclk_per_intf - Calculate uncompressed pclk per line. + * @dsc: Pointer to drm dsc config struct + * + * Note: This value will then be passed along to DSI and DP to calculate pclk_per_intf. + * This is because DSI and DP divide the uncompressed pclk_per_intf by different + * values depending on if widebus is enabled. + */ +int msm_dsc_get_uncompressed_pclk_per_intf(struct drm_dsc_config *dsc); +#endif /* MSM_DSC_HELPER_H_ */
Introduce MSM-specific DSC helper methods, as some calculations are common between DP and DSC. Changes in v2: - Moved files up to msm/ directory - Dropped get_comp_ratio() helper - Used drm_int2fixp() to convert to integers to fp - Style changes to improve readability - Dropped unused bpp variable in msm_dsc_get_dce_bytes_per_line() - Changed msm_dsc_get_slice_per_intf() to a static inline method - Dropped last division step of msm_dsc_get_pclk_per_line() and changed method name accordingly - Changed DSC_BPP macro to drm_dsc_get_bpp_int() helper method - Fixed some math issues caused by passing in incorrect types to drm_fixed methods in get_bytes_per_soft_slice() Changes in v3: - Dropped src_bpp parameter from all methods -- src_bpp can be calculated as dsc->bits_per_component * 3 - Dropped intf_width parameter from get_bytes_per_soft_slice() - Moved dsc->bits_per_component to numerator calculation in get_bytes_per_soft_slice() - Renamed msm_dsc_get_uncompressed_pclk_per_line to *_get_uncompressed_pclk_per_intf() - Removed dsc->slice_width check from msm_dsc_get_uncompressed_pclk_per_intf() - Made get_bytes_per_soft_slice() a public method (this will be called later to help calculate DP pclk params) - Added documentation in comments - Moved extra_eol_bytes math out of msm_dsc_get_eol_byte_num() and renamed msm_dsc_get_eol_byte_num to *_get_bytes_per_intf. Signed-off-by: Jessica Zhang <quic_jesszhan@quicinc.com> --- drivers/gpu/drm/msm/Makefile | 1 + drivers/gpu/drm/msm/msm_dsc_helper.c | 47 ++++++++++++++++++++++++ drivers/gpu/drm/msm/msm_dsc_helper.h | 70 ++++++++++++++++++++++++++++++++++++ 3 files changed, 118 insertions(+)