1 // SPDX-License-Identifier: MIT
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29 #if defined(CONFIG_X86)
30 #include <asm/fpu/api.h>
31 #elif defined(CONFIG_PPC64)
32 #include <asm/switch_to.h>
33 #include <asm/cputable.h>
34 #elif defined(CONFIG_ARM64)
36 #elif defined(CONFIG_LOONGARCH)
41 * DOC: DC FPU manipulation overview
43 * DC core uses FPU operations in multiple parts of the code, which requires a
44 * more specialized way to manage these areas' entrance. To fulfill this
45 * requirement, we created some wrapper functions that encapsulate
46 * kernel_fpu_begin/end to better fit our need in the display component. In
47 * summary, in this file, you can find functions related to FPU operation
51 static DEFINE_PER_CPU(int, fpu_recursion_depth);
54 * dc_assert_fp_enabled - Check if FPU protection is enabled
56 * This function tells if the code is already under FPU protection or not. A
57 * function that works as an API for a set of FPU operations can use this
58 * function for checking if the caller invoked it after DC_FP_START(). For
59 * example, take a look at dcn20_fpu.c file.
61 inline void dc_assert_fp_enabled(void)
65 depth = __this_cpu_read(fpu_recursion_depth);
71 * dc_fpu_begin - Enables FPU protection
72 * @function_name: A string containing the function name for debug purposes
75 * @line: A line number where DC_FP_START was invoked for debug purpose
78 * This function is responsible for managing the use of kernel_fpu_begin() with
79 * the advantage of providing an event trace for debugging.
81 * Note: Do not call this function directly; always use DC_FP_START().
83 void dc_fpu_begin(const char *function_name, const int line)
87 WARN_ON_ONCE(!in_task());
89 depth = __this_cpu_inc_return(fpu_recursion_depth);
92 #if defined(CONFIG_X86) || defined(CONFIG_LOONGARCH)
94 #elif defined(CONFIG_PPC64)
95 if (cpu_has_feature(CPU_FTR_VSX_COMP))
97 else if (cpu_has_feature(CPU_FTR_ALTIVEC_COMP))
98 enable_kernel_altivec();
99 else if (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE))
101 #elif defined(CONFIG_ARM64)
106 TRACE_DCN_FPU(true, function_name, line, depth);
110 * dc_fpu_end - Disable FPU protection
111 * @function_name: A string containing the function name for debug purposes
112 * @line: A-line number where DC_FP_END was invoked for debug purpose
114 * This function is responsible for managing the use of kernel_fpu_end() with
115 * the advantage of providing an event trace for debugging.
117 * Note: Do not call this function directly; always use DC_FP_END().
119 void dc_fpu_end(const char *function_name, const int line)
123 depth = __this_cpu_dec_return(fpu_recursion_depth);
125 #if defined(CONFIG_X86) || defined(CONFIG_LOONGARCH)
127 #elif defined(CONFIG_PPC64)
128 if (cpu_has_feature(CPU_FTR_VSX_COMP))
129 disable_kernel_vsx();
130 else if (cpu_has_feature(CPU_FTR_ALTIVEC_COMP))
131 disable_kernel_altivec();
132 else if (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE))
134 #elif defined(CONFIG_ARM64)
138 WARN_ON_ONCE(depth < 0);
141 TRACE_DCN_FPU(false, function_name, line, depth);