drivers/gpu/drm/amd/display/dc/dml/calcs/dcn_calc_math.c
Source file repositories/reference/linux-study-clean/drivers/gpu/drm/amd/display/dc/dml/calcs/dcn_calc_math.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/gpu/drm/amd/display/dc/dml/calcs/dcn_calc_math.c- Extension
.c- Size
- 3662 bytes
- Lines
- 146
- Domain
- Driver Families
- Bucket
- drivers/gpu
- Inferred role
- Driver Families: implementation source
- Status
- source implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
Dependency Surface
os_types.hdcn_calc_math.h
Detected Declarations
function filesfunction dcn_bw_min2function dcn_bw_maxfunction dcn_bw_max2function dcn_bw_floor2function dcn_bw_floorfunction dcn_bw_ceilfunction dcn_bw_ceil2function dcn_bw_max3function dcn_bw_max5function dcn_bw_powfunction dcn_bw_fabsfunction dcn_bw_log
Annotated Snippet
#include "os_types.h"
#include "dcn_calc_math.h"
#define isNaN(number) ((number) != (number))
/*
* NOTE:
* This file is gcc-parseable HW gospel, coming straight from HW engineers.
*
* It doesn't adhere to Linux kernel style and sometimes will do things in odd
* ways. Unless there is something clearly wrong with it the code should
* remain as-is as it provides us with a guarantee from HW that it is correct.
*/
float dcn_bw_mod(const float arg1, const float arg2)
{
if (isNaN(arg1))
return arg2;
if (isNaN(arg2))
return arg1;
return arg1 - arg1 * ((int) (arg1 / arg2));
}
float dcn_bw_min2(const float arg1, const float arg2)
{
if (isNaN(arg1))
return arg2;
if (isNaN(arg2))
return arg1;
return arg1 < arg2 ? arg1 : arg2;
}
unsigned int dcn_bw_max(const unsigned int arg1, const unsigned int arg2)
{
return arg1 > arg2 ? arg1 : arg2;
}
float dcn_bw_max2(const float arg1, const float arg2)
{
if (isNaN(arg1))
return arg2;
if (isNaN(arg2))
return arg1;
return arg1 > arg2 ? arg1 : arg2;
}
float dcn_bw_floor2(const float arg, const float significance)
{
ASSERT(significance != 0);
return ((int) (arg / significance)) * significance;
}
float dcn_bw_floor(const float arg)
{
return (float)((int)(arg));
}
float dcn_bw_ceil(const float arg)
{
return (float)((int)(arg + 0.99999f));
}
float dcn_bw_ceil2(const float arg, const float significance)
{
ASSERT(significance != 0);
return ((int) (arg / significance + 0.99999)) * significance;
}
float dcn_bw_max3(float v1, float v2, float v3)
{
return v3 > dcn_bw_max2(v1, v2) ? v3 : dcn_bw_max2(v1, v2);
}
float dcn_bw_max5(float v1, float v2, float v3, float v4, float v5)
{
return dcn_bw_max3(v1, v2, v3) > dcn_bw_max2(v4, v5) ? dcn_bw_max3(v1, v2, v3) : dcn_bw_max2(v4, v5);
}
float dcn_bw_pow(float a, float exp)
{
float temp;
/*ASSERT(exp == (int)exp);*/
if ((int)exp == 0)
return 1;
temp = dcn_bw_pow(a, (float)((int)(exp / 2)));
if (((int)exp % 2) == 0) {
return temp * temp;
} else {
if ((int)exp > 0)
return a * temp * temp;
Annotation
- Immediate include surface: `os_types.h`, `dcn_calc_math.h`.
- Detected declarations: `function files`, `function dcn_bw_min2`, `function dcn_bw_max`, `function dcn_bw_max2`, `function dcn_bw_floor2`, `function dcn_bw_floor`, `function dcn_bw_ceil`, `function dcn_bw_ceil2`, `function dcn_bw_max3`, `function dcn_bw_max5`.
- Atlas domain: Driver Families / drivers/gpu.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.