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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/m32r/lib/delay.c
Initial import
Diffstat (limited to 'arch/m32r/lib/delay.c')
-rw-r--r--arch/m32r/lib/delay.c129
1 files changed, 129 insertions, 0 deletions
diff --git a/arch/m32r/lib/delay.c b/arch/m32r/lib/delay.c
new file mode 100644
index 000000000..940f4837e
--- /dev/null
+++ b/arch/m32r/lib/delay.c
@@ -0,0 +1,129 @@
+/*
+ * linux/arch/m32r/lib/delay.c
+ *
+ * Copyright (c) 2002 Hitoshi Yamamoto, Hirokazu Takata
+ * Copyright (c) 2004 Hirokazu Takata
+ */
+
+#include <linux/param.h>
+#include <linux/module.h>
+#ifdef CONFIG_SMP
+#include <linux/sched.h>
+#include <asm/current.h>
+#include <asm/smp.h>
+#endif /* CONFIG_SMP */
+#include <asm/processor.h>
+
+void __delay(unsigned long loops)
+{
+#ifdef CONFIG_ISA_DUAL_ISSUE
+ __asm__ __volatile__ (
+ "beqz %0, 2f \n\t"
+ "addi %0, #-1 \n\t"
+
+ " .fillinsn \n\t"
+ "1: \n\t"
+ "cmpz %0 || addi %0, #-1 \n\t"
+ "bc 2f || cmpz %0 \n\t"
+ "bc 2f || addi %0, #-1 \n\t"
+ "cmpz %0 || addi %0, #-1 \n\t"
+ "bc 2f || cmpz %0 \n\t"
+ "bnc 1b || addi %0, #-1 \n\t"
+ " .fillinsn \n\t"
+ "2: \n\t"
+ : "+r" (loops)
+ : "r" (0)
+ : "cbit"
+ );
+#else
+ __asm__ __volatile__ (
+ "beqz %0, 2f \n\t"
+ " .fillinsn \n\t"
+ "1: \n\t"
+ "addi %0, #-1 \n\t"
+ "blez %0, 2f \n\t"
+ "addi %0, #-1 \n\t"
+ "blez %0, 2f \n\t"
+ "addi %0, #-1 \n\t"
+ "blez %0, 2f \n\t"
+ "addi %0, #-1 \n\t"
+ "bgtz %0, 1b \n\t"
+ " .fillinsn \n\t"
+ "2: \n\t"
+ : "+r" (loops)
+ : "r" (0)
+ );
+#endif
+}
+
+void __const_udelay(unsigned long xloops)
+{
+#if defined(CONFIG_ISA_M32R2) && defined(CONFIG_ISA_DSP_LEVEL2)
+ /*
+ * loops [1] = (xloops >> 32) [sec] * loops_per_jiffy [1/jiffy]
+ * * HZ [jiffy/sec]
+ * = (xloops >> 32) [sec] * (loops_per_jiffy * HZ) [1/sec]
+ * = (((xloops * loops_per_jiffy) >> 32) * HZ) [1]
+ *
+ * NOTE:
+ * - '[]' depicts variable's dimension in the above equation.
+ * - "rac" instruction rounds the accumulator in word size.
+ */
+ __asm__ __volatile__ (
+ "srli %0, #1 \n\t"
+ "mulwhi %0, %1 ; a0 \n\t"
+ "mulwu1 %0, %1 ; a1 \n\t"
+ "sadd ; a0 += (a1 >> 16) \n\t"
+ "rac a0, a0, #1 \n\t"
+ "mvfacmi %0, a0 \n\t"
+ : "+r" (xloops)
+ : "r" (current_cpu_data.loops_per_jiffy)
+ : "a0", "a1"
+ );
+#elif defined(CONFIG_ISA_M32R2) || defined(CONFIG_ISA_M32R)
+ /*
+ * u64 ull;
+ * ull = (u64)xloops * (u64)current_cpu_data.loops_per_jiffy;
+ * xloops = (ull >> 32);
+ */
+ __asm__ __volatile__ (
+ "and3 r4, %0, #0xffff \n\t"
+ "and3 r5, %1, #0xffff \n\t"
+ "mul r4, r5 \n\t"
+ "srl3 r6, %0, #16 \n\t"
+ "srli r4, #16 \n\t"
+ "mul r5, r6 \n\t"
+ "add r4, r5 \n\t"
+ "and3 r5, %0, #0xffff \n\t"
+ "srl3 r6, %1, #16 \n\t"
+ "mul r5, r6 \n\t"
+ "add r4, r5 \n\t"
+ "srl3 r5, %0, #16 \n\t"
+ "srli r4, #16 \n\t"
+ "mul r5, r6 \n\t"
+ "add r4, r5 \n\t"
+ "mv %0, r4 \n\t"
+ : "+r" (xloops)
+ : "r" (current_cpu_data.loops_per_jiffy)
+ : "r4", "r5", "r6"
+ );
+#else
+#error unknown isa configuration
+#endif
+ __delay(xloops * HZ);
+}
+
+void __udelay(unsigned long usecs)
+{
+ __const_udelay(usecs * 0x000010c7); /* 2**32 / 1000000 (rounded up) */
+}
+
+void __ndelay(unsigned long nsecs)
+{
+ __const_udelay(nsecs * 0x00005); /* 2**32 / 1000000000 (rounded up) */
+}
+
+EXPORT_SYMBOL(__delay);
+EXPORT_SYMBOL(__const_udelay);
+EXPORT_SYMBOL(__udelay);
+EXPORT_SYMBOL(__ndelay);