LoongArch: Architectural preparation for AVEC irqchip

Add architectural preparation for AVEC irqchip, including:
1. CPUCFG feature bits definition for AVEC;
2. Detection of AVEC irqchip in cpu_probe();
3. New IPI type definition (IPI_CLEAR_VECTOR) for AVEC;
4. Provide arch_probe_nr_irqs() for large NR_IRQS;
5. Other related changes about the number of interrupts.

Signed-off-by: Huacai Chen <[email protected]>
Signed-off-by: Tianyang Zhang <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/all/[email protected]

Author: chenhuacai

arch/loongarch/include/asm/cpu-features.h

@@ -65,5 +65,6 @@
 #define cpu_has_guestid		cpu_opt(LOONGARCH_CPU_GUESTID)
 #define cpu_has_hypervisor	cpu_opt(LOONGARCH_CPU_HYPERVISOR)
 #define cpu_has_ptw		cpu_opt(LOONGARCH_CPU_PTW)
+#define cpu_has_avecint		cpu_opt(LOONGARCH_CPU_AVECINT)
 
 #endif /* __ASM_CPU_FEATURES_H */

arch/loongarch/include/asm/cpu.h

@@ -99,6 +99,7 @@ enum cpu_type_enum {
 #define CPU_FEATURE_GUESTID		24	/* CPU has GuestID feature */
 #define CPU_FEATURE_HYPERVISOR		25	/* CPU has hypervisor (running in VM) */
 #define CPU_FEATURE_PTW			26	/* CPU has hardware page table walker */
+#define CPU_FEATURE_AVECINT		27	/* CPU has avec interrupt */
 
 #define LOONGARCH_CPU_CPUCFG		BIT_ULL(CPU_FEATURE_CPUCFG)
 #define LOONGARCH_CPU_LAM		BIT_ULL(CPU_FEATURE_LAM)
@@ -127,5 +128,6 @@ enum cpu_type_enum {
 #define LOONGARCH_CPU_GUESTID		BIT_ULL(CPU_FEATURE_GUESTID)
 #define LOONGARCH_CPU_HYPERVISOR	BIT_ULL(CPU_FEATURE_HYPERVISOR)
 #define LOONGARCH_CPU_PTW		BIT_ULL(CPU_FEATURE_PTW)
+#define LOONGARCH_CPU_AVECINT		BIT_ULL(CPU_FEATURE_AVECINT)
 
 #endif /* _ASM_CPU_H */

arch/loongarch/include/asm/hardirq.h

@@ -12,12 +12,13 @@
 extern void ack_bad_irq(unsigned int irq);
 #define ack_bad_irq ack_bad_irq
 
-#define NR_IPI	3
+#define NR_IPI	4
 
 enum ipi_msg_type {
 	IPI_RESCHEDULE,
 	IPI_CALL_FUNCTION,
 	IPI_IRQ_WORK,
+	IPI_CLEAR_VECTOR,
 };
 
 typedef struct {

arch/loongarch/include/asm/irq.h

@@ -39,11 +39,22 @@ void spurious_interrupt(void);
 
 #define NR_IRQS_LEGACY 16
 
+/*
+ * 256 Vectors Mapping for AVECINTC:
+ *
+ * 0 - 15: Mapping classic IPs, e.g. IP0-12.
+ * 16 - 255: Mapping vectors for external IRQ.
+ *
+ */
+#define NR_VECTORS		256
+#define NR_LEGACY_VECTORS	16
+#define IRQ_MATRIX_BITS		NR_VECTORS
+
 #define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
 void arch_trigger_cpumask_backtrace(const struct cpumask *mask, int exclude_cpu);
 
 #define MAX_IO_PICS 2
-#define NR_IRQS	(64 + (256 * MAX_IO_PICS))
+#define NR_IRQS	(64 + NR_VECTORS * (NR_CPUS + MAX_IO_PICS))
 
 struct acpi_vector_group {
 	int node;
@@ -65,7 +76,7 @@ extern struct acpi_vector_group msi_group[MAX_IO_PICS];
 #define LOONGSON_LPC_LAST_IRQ		(LOONGSON_LPC_IRQ_BASE + 15)
 
 #define LOONGSON_CPU_IRQ_BASE		16
-#define LOONGSON_CPU_LAST_IRQ		(LOONGSON_CPU_IRQ_BASE + 14)
+#define LOONGSON_CPU_LAST_IRQ		(LOONGSON_CPU_IRQ_BASE + 15)
 
 #define LOONGSON_PCH_IRQ_BASE		64
 #define LOONGSON_PCH_ACPI_IRQ		(LOONGSON_PCH_IRQ_BASE + 47)

arch/loongarch/include/asm/loongarch.h

@@ -253,8 +253,8 @@
 #define  CSR_ESTAT_EXC_WIDTH		6
 #define  CSR_ESTAT_EXC			(_ULCAST_(0x3f) << CSR_ESTAT_EXC_SHIFT)
 #define  CSR_ESTAT_IS_SHIFT		0
-#define  CSR_ESTAT_IS_WIDTH		14
-#define  CSR_ESTAT_IS			(_ULCAST_(0x3fff) << CSR_ESTAT_IS_SHIFT)
+#define  CSR_ESTAT_IS_WIDTH		15
+#define  CSR_ESTAT_IS			(_ULCAST_(0x7fff) << CSR_ESTAT_IS_SHIFT)
 
 #define LOONGARCH_CSR_ERA		0x6	/* ERA */
 
@@ -649,6 +649,13 @@
 
 #define LOONGARCH_CSR_CTAG		0x98	/* TagLo + TagHi */
 
+#define LOONGARCH_CSR_ISR0		0xa0
+#define LOONGARCH_CSR_ISR1		0xa1
+#define LOONGARCH_CSR_ISR2		0xa2
+#define LOONGARCH_CSR_ISR3		0xa3
+
+#define LOONGARCH_CSR_IRR		0xa4
+
 #define LOONGARCH_CSR_PRID		0xc0
 
 /* Shadow MCSR : 0xc0 ~ 0xff */
@@ -1011,7 +1018,7 @@
 /*
  * CSR_ECFG IM
  */
-#define ECFG0_IM		0x00001fff
+#define ECFG0_IM		0x00005fff
 #define ECFGB_SIP0		0
 #define ECFGF_SIP0		(_ULCAST_(1) << ECFGB_SIP0)
 #define ECFGB_SIP1		1
@@ -1054,6 +1061,7 @@
 #define  IOCSRF_EIODECODE		BIT_ULL(9)
 #define  IOCSRF_FLATMODE		BIT_ULL(10)
 #define  IOCSRF_VM			BIT_ULL(11)
+#define  IOCSRF_AVEC			BIT_ULL(15)
 
 #define LOONGARCH_IOCSR_VENDOR		0x10
 
@@ -1065,6 +1073,7 @@
 #define  IOCSR_MISC_FUNC_SOFT_INT	BIT_ULL(10)
 #define  IOCSR_MISC_FUNC_TIMER_RESET	BIT_ULL(21)
 #define  IOCSR_MISC_FUNC_EXT_IOI_EN	BIT_ULL(48)
+#define  IOCSR_MISC_FUNC_AVEC_EN	BIT_ULL(51)
 
 #define LOONGARCH_IOCSR_CPUTEMP		0x428
 
@@ -1387,9 +1396,10 @@ __BUILD_CSR_OP(tlbidx)
 #define INT_TI		11	/* Timer */
 #define INT_IPI		12
 #define INT_NMI		13
+#define INT_AVEC	14
 
 /* ExcCodes corresponding to interrupts */
-#define EXCCODE_INT_NUM		(INT_NMI + 1)
+#define EXCCODE_INT_NUM		(INT_AVEC + 1)
 #define EXCCODE_INT_START	64
 #define EXCCODE_INT_END		(EXCCODE_INT_START + EXCCODE_INT_NUM - 1)
 

arch/loongarch/include/asm/smp.h

@@ -70,10 +70,12 @@ extern int __cpu_logical_map[NR_CPUS];
 #define ACTION_RESCHEDULE	1
 #define ACTION_CALL_FUNCTION	2
 #define ACTION_IRQ_WORK		3
+#define ACTION_CLEAR_VECTOR	4
 #define SMP_BOOT_CPU		BIT(ACTION_BOOT_CPU)
 #define SMP_RESCHEDULE		BIT(ACTION_RESCHEDULE)
 #define SMP_CALL_FUNCTION	BIT(ACTION_CALL_FUNCTION)
 #define SMP_IRQ_WORK		BIT(ACTION_IRQ_WORK)
+#define SMP_CLEAR_VECTOR	BIT(ACTION_CLEAR_VECTOR)
 
 struct secondary_data {
 	unsigned long stack;

arch/loongarch/kernel/cpu-probe.c

@@ -106,7 +106,6 @@ static void cpu_probe_common(struct cpuinfo_loongarch *c)
 		elf_hwcap |= HWCAP_LOONGARCH_CRC32;
 	}
 
-
 	config = read_cpucfg(LOONGARCH_CPUCFG2);
 	if (config & CPUCFG2_LAM) {
 		c->options |= LOONGARCH_CPU_LAM;
@@ -174,6 +173,8 @@ static void cpu_probe_common(struct cpuinfo_loongarch *c)
 		c->options |= LOONGARCH_CPU_FLATMODE;
 	if (config & IOCSRF_EIODECODE)
 		c->options |= LOONGARCH_CPU_EIODECODE;
+	if (config & IOCSRF_AVEC)
+		c->options |= LOONGARCH_CPU_AVECINT;
 	if (config & IOCSRF_VM)
 		c->options |= LOONGARCH_CPU_HYPERVISOR;
 

arch/loongarch/kernel/irq.c

@@ -87,6 +87,18 @@ static void __init init_vec_parent_group(void)
 	acpi_table_parse(ACPI_SIG_MCFG, early_pci_mcfg_parse);
 }
 
+int __init arch_probe_nr_irqs(void)
+{
+	int nr_io_pics = bitmap_weight(loongson_sysconf.cores_io_master, NR_CPUS);
+
+	if (!cpu_has_avecint)
+		nr_irqs = (64 + NR_VECTORS * nr_io_pics);
+	else
+		nr_irqs = (64 + NR_VECTORS * (nr_cpu_ids + nr_io_pics));
+
+	return NR_IRQS_LEGACY;
+}
+
 void __init init_IRQ(void)
 {
 	int i;