KVM: LoongArch: selftests: Add timer interrupt test case

Add timer test case based on common arch_timer code, timer interrupt
with one-shot and period mode is tested.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

2 files changed, 95 insertions, 0 deletions

diff --git a/tools/testing/selftests/kvm/include/loongarch/arch_timer.h b/tools/testing/selftests/kvm/include/loongarch/arch_timer.h
new file mode 100644
index 000000000000..2ed106b32c81
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/loongarch/arch_timer.h
@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * LoongArch Constant Timer specific interface
+ */
+#ifndef SELFTEST_KVM_ARCH_TIMER_H
+#define SELFTEST_KVM_ARCH_TIMER_H
+
+#include "processor.h"
+
+/* LoongArch timer frequency is constant 100MHZ */
+#define TIMER_FREQ		(100UL << 20)
+#define msec_to_cycles(msec)	(TIMER_FREQ * (unsigned long)(msec) / 1000)
+#define usec_to_cycles(usec)	(TIMER_FREQ * (unsigned long)(usec) / 1000000)
+#define cycles_to_usec(cycles)	((unsigned long)(cycles) * 1000000 / TIMER_FREQ)
+
+static inline unsigned long timer_get_cycles(void)
+{
+	unsigned long val = 0;
+
+	__asm__ __volatile__(
+		"rdtime.d %0, $zero\n\t"
+		: "=r"(val)
+		:
+	);
+
+	return val;
+}
+
+static inline unsigned long timer_get_cfg(void)
+{
+	return csr_read(LOONGARCH_CSR_TCFG);
+}
+
+static inline unsigned long timer_get_val(void)
+{
+	return csr_read(LOONGARCH_CSR_TVAL);
+}
+
+static inline void disable_timer(void)
+{
+	csr_write(0, LOONGARCH_CSR_TCFG);
+}
+
+static inline void timer_irq_enable(void)
+{
+	unsigned long val;
+
+	val = csr_read(LOONGARCH_CSR_ECFG);
+	val |= ECFGF_TIMER;
+	csr_write(val, LOONGARCH_CSR_ECFG);
+}
+
+static inline void timer_irq_disable(void)
+{
+	unsigned long val;
+
+	val = csr_read(LOONGARCH_CSR_ECFG);
+	val &= ~ECFGF_TIMER;
+	csr_write(val, LOONGARCH_CSR_ECFG);
+}
+
+static inline void timer_set_next_cmp_ms(unsigned int msec, bool period)
+{
+	unsigned long val;
+
+	val = msec_to_cycles(msec) & CSR_TCFG_VAL;
+	val |= CSR_TCFG_EN;
+	if (period)
+		val |= CSR_TCFG_PERIOD;
+	csr_write(val, LOONGARCH_CSR_TCFG);
+}
+
+static inline void __delay(uint64_t cycles)
+{
+	uint64_t start = timer_get_cycles();
+
+	while ((timer_get_cycles() - start) < cycles)
+		cpu_relax();
+}
+
+static inline void udelay(unsigned long usec)
+{
+	__delay(usec_to_cycles(usec));
+}
+#endif /* SELFTEST_KVM_ARCH_TIMER_H */
diff --git a/tools/testing/selftests/kvm/include/loongarch/processor.h b/tools/testing/selftests/kvm/include/loongarch/processor.h
index a1930f28e044..76840ddda57d 100644
--- a/tools/testing/selftests/kvm/include/loongarch/processor.h
+++ b/tools/testing/selftests/kvm/include/loongarch/processor.h
@@ -83,6 +83,8 @@
 #define LOONGARCH_CSR_PRMD		0x1
 #define LOONGARCH_CSR_EUEN		0x2
 #define LOONGARCH_CSR_ECFG		0x4
+#define  ECFGB_TIMER			11
+#define  ECFGF_TIMER			(BIT_ULL(ECFGB_TIMER))
 #define LOONGARCH_CSR_ESTAT		0x5  /* Exception status */
 #define  CSR_ESTAT_EXC_SHIFT		16
 #define  CSR_ESTAT_EXC_WIDTH		6
@@ -111,6 +113,14 @@
 #define LOONGARCH_CSR_KS1		0x31
 #define LOONGARCH_CSR_TMID		0x40
 #define LOONGARCH_CSR_TCFG		0x41
+#define  CSR_TCFG_VAL			(BIT_ULL(48) - BIT_ULL(2))
+#define  CSR_TCFG_PERIOD_SHIFT		1
+#define  CSR_TCFG_PERIOD		(0x1UL << CSR_TCFG_PERIOD_SHIFT)
+#define  CSR_TCFG_EN			(0x1UL)
+#define LOONGARCH_CSR_TVAL		0x42
+#define LOONGARCH_CSR_TINTCLR		0x44 /* Timer interrupt clear */
+#define  CSR_TINTCLR_TI_SHIFT		0
+#define  CSR_TINTCLR_TI			(1 << CSR_TINTCLR_TI_SHIFT)
 /* TLB refill exception entry */
 #define LOONGARCH_CSR_TLBRENTRY		0x88
 #define LOONGARCH_CSR_TLBRSAVE		0x8b