lib: utils/irqchip: Add APLIC initialization library

We add simple APLIC initialization library which is independent of
hardware description format (FDT or ACPI). This APLIC initialization
library can be used by custom OpenSBI platform support to setup
APLIC domains.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>

3 files changed, 327 insertions, 0 deletions

diff --git a/include/sbi_utils/irqchip/aplic.h b/include/sbi_utils/irqchip/aplic.h
new file mode 100644
index 0000000..82682e8
--- /dev/null
+++ b/include/sbi_utils/irqchip/aplic.h
@@ -0,0 +1,47 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2021 Western Digital Corporation or its affiliates.
+ * Copyright (c) 2022 Ventana Micro Systems Inc.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ */
+
+#ifndef __IRQCHIP_APLIC_H__
+#define __IRQCHIP_APLIC_H__
+
+#include <sbi/sbi_types.h>
+
+#define APLIC_MAX_DELEGATE	16
+
+struct aplic_msicfg_data {
+	unsigned long lhxs;
+	unsigned long lhxw;
+	unsigned long hhxs;
+	unsigned long hhxw;
+	unsigned long base_addr;
+};
+
+struct aplic_delegate_data {
+	u32 first_irq;
+	u32 last_irq;
+	u32 child_index;
+};
+
+struct aplic_data {
+	unsigned long addr;
+	unsigned long size;
+	unsigned long num_idc;
+	unsigned long num_source;
+	bool targets_mmode;
+	bool has_msicfg_mmode;
+	struct aplic_msicfg_data msicfg_mmode;
+	bool has_msicfg_smode;
+	struct aplic_msicfg_data msicfg_smode;
+	struct aplic_delegate_data delegate[APLIC_MAX_DELEGATE];
+};
+
+int aplic_cold_irqchip_init(struct aplic_data *aplic);
+
+#endif
diff --git a/lib/utils/irqchip/aplic.c b/lib/utils/irqchip/aplic.c
new file mode 100644
index 0000000..0a8469b
--- /dev/null
+++ b/lib/utils/irqchip/aplic.c
@@ -0,0 +1,279 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2021 Western Digital Corporation or its affiliates.
+ * Copyright (c) 2022 Ventana Micro Systems Inc.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ */
+
+#include <sbi/riscv_io.h>
+#include <sbi/sbi_console.h>
+#include <sbi/sbi_domain.h>
+#include <sbi/sbi_error.h>
+#include <sbi_utils/irqchip/aplic.h>
+
+#define APLIC_MAX_IDC			(1UL << 14)
+#define APLIC_MAX_SOURCE		1024
+
+#define APLIC_DOMAINCFG		0x0000
+#define APLIC_DOMAINCFG_IE		(1 << 8)
+#define APLIC_DOMAINCFG_DM		(1 << 2)
+#define APLIC_DOMAINCFG_BE		(1 << 0)
+
+#define APLIC_SOURCECFG_BASE		0x0004
+#define APLIC_SOURCECFG_D		(1 << 10)
+#define APLIC_SOURCECFG_CHILDIDX_MASK	0x000003ff
+#define APLIC_SOURCECFG_SM_MASK	0x00000007
+#define APLIC_SOURCECFG_SM_INACTIVE	0x0
+#define APLIC_SOURCECFG_SM_DETACH	0x1
+#define APLIC_SOURCECFG_SM_EDGE_RISE	0x4
+#define APLIC_SOURCECFG_SM_EDGE_FALL	0x5
+#define APLIC_SOURCECFG_SM_LEVEL_HIGH	0x6
+#define APLIC_SOURCECFG_SM_LEVEL_LOW	0x7
+
+#define APLIC_MMSICFGADDR		0x1bc0
+#define APLIC_MMSICFGADDRH		0x1bc4
+#define APLIC_SMSICFGADDR		0x1bc8
+#define APLIC_SMSICFGADDRH		0x1bcc
+
+#define APLIC_xMSICFGADDRH_L		(1UL << 31)
+#define APLIC_xMSICFGADDRH_HHXS_MASK	0x1f
+#define APLIC_xMSICFGADDRH_HHXS_SHIFT	24
+#define APLIC_xMSICFGADDRH_LHXS_MASK	0x7
+#define APLIC_xMSICFGADDRH_LHXS_SHIFT	20
+#define APLIC_xMSICFGADDRH_HHXW_MASK	0x7
+#define APLIC_xMSICFGADDRH_HHXW_SHIFT	16
+#define APLIC_xMSICFGADDRH_LHXW_MASK	0xf
+#define APLIC_xMSICFGADDRH_LHXW_SHIFT	12
+#define APLIC_xMSICFGADDRH_BAPPN_MASK	0xfff
+
+#define APLIC_xMSICFGADDR_PPN_SHIFT	12
+
+#define APLIC_xMSICFGADDR_PPN_HART(__lhxs) \
+	((1UL << (__lhxs)) - 1)
+
+#define APLIC_xMSICFGADDR_PPN_LHX_MASK(__lhxw) \
+	((1UL << (__lhxw)) - 1)
+#define APLIC_xMSICFGADDR_PPN_LHX_SHIFT(__lhxs) \
+	((__lhxs))
+#define APLIC_xMSICFGADDR_PPN_LHX(__lhxw, __lhxs) \
+	(APLIC_xMSICFGADDR_PPN_LHX_MASK(__lhxw) << \
+	 APLIC_xMSICFGADDR_PPN_LHX_SHIFT(__lhxs))
+
+#define APLIC_xMSICFGADDR_PPN_HHX_MASK(__hhxw) \
+	((1UL << (__hhxw)) - 1)
+#define APLIC_xMSICFGADDR_PPN_HHX_SHIFT(__hhxs) \
+	((__hhxs) + APLIC_xMSICFGADDR_PPN_SHIFT)
+#define APLIC_xMSICFGADDR_PPN_HHX(__hhxw, __hhxs) \
+	(APLIC_xMSICFGADDR_PPN_HHX_MASK(__hhxw) << \
+	 APLIC_xMSICFGADDR_PPN_HHX_SHIFT(__hhxs))
+
+#define APLIC_SETIP_BASE		0x1c00
+#define APLIC_SETIPNUM			0x1cdc
+
+#define APLIC_CLRIP_BASE		0x1d00
+#define APLIC_CLRIPNUM			0x1ddc
+
+#define APLIC_SETIE_BASE		0x1e00
+#define APLIC_SETIENUM			0x1edc
+
+#define APLIC_CLRIE_BASE		0x1f00
+#define APLIC_CLRIENUM			0x1fdc
+
+#define APLIC_SETIPNUM_LE		0x2000
+#define APLIC_SETIPNUM_BE		0x2004
+
+#define APLIC_TARGET_BASE		0x3004
+#define APLIC_TARGET_HART_IDX_SHIFT	18
+#define APLIC_TARGET_HART_IDX_MASK	0x3fff
+#define APLIC_TARGET_GUEST_IDX_SHIFT	12
+#define APLIC_TARGET_GUEST_IDX_MASK	0x3f
+#define APLIC_TARGET_IPRIO_MASK	0xff
+#define APLIC_TARGET_EIID_MASK	0x7ff
+
+#define APLIC_IDC_BASE			0x4000
+#define APLIC_IDC_SIZE			32
+
+#define APLIC_IDC_IDELIVERY		0x00
+
+#define APLIC_IDC_IFORCE		0x04
+
+#define APLIC_IDC_ITHRESHOLD		0x08
+
+#define APLIC_IDC_TOPI			0x18
+#define APLIC_IDC_TOPI_ID_SHIFT	16
+#define APLIC_IDC_TOPI_ID_MASK	0x3ff
+#define APLIC_IDC_TOPI_PRIO_MASK	0xff
+
+#define APLIC_IDC_CLAIMI		0x1c
+
+#define APLIC_DEFAULT_PRIORITY		1
+#define APLIC_DISABLE_IDELIVERY		0
+#define APLIC_ENABLE_IDELIVERY		1
+#define APLIC_DISABLE_ITHRESHOLD	1
+#define APLIC_ENABLE_ITHRESHOLD		0
+
+static void aplic_writel_msicfg(struct aplic_msicfg_data *msicfg,
+				void *msicfgaddr, void *msicfgaddrH)
+{
+	u32 val;
+	unsigned long base_ppn;
+
+	/* Check if MSI config is already locked */
+	if (readl(msicfgaddrH) & APLIC_xMSICFGADDRH_L)
+		return;
+
+	/* Compute the MSI base PPN */
+	base_ppn = msicfg->base_addr >> APLIC_xMSICFGADDR_PPN_SHIFT;
+	base_ppn &= ~APLIC_xMSICFGADDR_PPN_HART(msicfg->lhxs);
+	base_ppn &= ~APLIC_xMSICFGADDR_PPN_LHX(msicfg->lhxw, msicfg->lhxs);
+	base_ppn &= ~APLIC_xMSICFGADDR_PPN_HHX(msicfg->hhxw, msicfg->hhxs);
+
+	/* Write the lower MSI config register */
+	writel((u32)base_ppn, msicfgaddr);
+
+	/* Write the upper MSI config register */
+	val = (((u64)base_ppn) >> 32) &
+		APLIC_xMSICFGADDRH_BAPPN_MASK;
+	val |= (msicfg->lhxw & APLIC_xMSICFGADDRH_LHXW_MASK)
+		<< APLIC_xMSICFGADDRH_LHXW_SHIFT;
+	val |= (msicfg->hhxw & APLIC_xMSICFGADDRH_HHXW_MASK)
+		<< APLIC_xMSICFGADDRH_HHXW_SHIFT;
+	val |= (msicfg->lhxs & APLIC_xMSICFGADDRH_LHXS_MASK)
+		<< APLIC_xMSICFGADDRH_LHXS_SHIFT;
+	val |= (msicfg->hhxs & APLIC_xMSICFGADDRH_HHXS_MASK)
+		<< APLIC_xMSICFGADDRH_HHXS_SHIFT;
+	writel(val, msicfgaddrH);
+}
+
+static int aplic_check_msicfg(struct aplic_msicfg_data *msicfg)
+{
+	if (APLIC_xMSICFGADDRH_LHXS_MASK < msicfg->lhxs)
+		return SBI_EINVAL;
+
+	if (APLIC_xMSICFGADDRH_LHXW_MASK < msicfg->lhxw)
+		return SBI_EINVAL;
+
+	if (APLIC_xMSICFGADDRH_HHXS_MASK < msicfg->hhxs)
+		return SBI_EINVAL;
+
+	if (APLIC_xMSICFGADDRH_HHXW_MASK < msicfg->hhxw)
+		return SBI_EINVAL;
+
+	return 0;
+}
+
+int aplic_cold_irqchip_init(struct aplic_data *aplic)
+{
+	int rc;
+	u32 i, j, tmp;
+	struct sbi_domain_memregion reg;
+	struct aplic_delegate_data *deleg;
+	u32 first_deleg_irq, last_deleg_irq;
+
+	/* Sanity checks */
+	if (!aplic ||
+	    !aplic->num_source || APLIC_MAX_SOURCE <= aplic->num_source ||
+	    APLIC_MAX_IDC <= aplic->num_idc)
+		return SBI_EINVAL;
+	if (aplic->targets_mmode && aplic->has_msicfg_mmode) {
+		rc = aplic_check_msicfg(&aplic->msicfg_mmode);
+		if (rc)
+			return rc;
+	}
+	if (aplic->targets_mmode && aplic->has_msicfg_smode) {
+		rc = aplic_check_msicfg(&aplic->msicfg_smode);
+		if (rc)
+			return rc;
+	}
+
+	/* Set domain configuration to 0 */
+	writel(0, (void *)(aplic->addr + APLIC_DOMAINCFG));
+
+	/* Disable all interrupts */
+	for (i = 0; i <= aplic->num_source; i++)
+		writel(-1U, (void *)(aplic->addr + APLIC_CLRIE_BASE +
+				     (i / 32) * sizeof(u32)));
+
+	/* Set interrupt type and priority for all interrupts */
+	for (i = 1; i <= aplic->num_source; i++) {
+		/* Set IRQ source configuration to 0 */
+		writel(0, (void *)(aplic->addr + APLIC_SOURCECFG_BASE +
+			  (i - 1) * sizeof(u32)));
+		/* Set IRQ target hart index and priority to 1 */
+		writel(APLIC_DEFAULT_PRIORITY, (void *)(aplic->addr +
+						APLIC_TARGET_BASE +
+						(i - 1) * sizeof(u32)));
+	}
+
+	/* Configure IRQ delegation */
+	first_deleg_irq = -1U;
+	last_deleg_irq = 0;
+	for (i = 0; i < APLIC_MAX_DELEGATE; i++) {
+		deleg = &aplic->delegate[i];
+		if (!deleg->first_irq || !deleg->last_irq)
+			continue;
+		if (aplic->num_source < deleg->first_irq ||
+		    aplic->num_source < deleg->last_irq)
+			continue;
+		if (APLIC_SOURCECFG_CHILDIDX_MASK < deleg->child_index)
+			continue;
+		if (deleg->first_irq > deleg->last_irq) {
+			tmp = deleg->first_irq;
+			deleg->first_irq = deleg->last_irq;
+			deleg->last_irq = tmp;
+		}
+		if (deleg->first_irq < first_deleg_irq)
+			first_deleg_irq = deleg->first_irq;
+		if (last_deleg_irq < deleg->last_irq)
+			last_deleg_irq = deleg->last_irq;
+		for (j = deleg->first_irq; j <= deleg->last_irq; j++)
+			writel(APLIC_SOURCECFG_D | deleg->child_index,
+				(void *)(aplic->addr + APLIC_SOURCECFG_BASE +
+				(j - 1) * sizeof(u32)));
+	}
+
+	/* Default initialization of IDC structures */
+	for (i = 0; i < aplic->num_idc; i++) {
+		writel(0, (void *)(aplic->addr + APLIC_IDC_BASE +
+			  i * APLIC_IDC_SIZE + APLIC_IDC_IDELIVERY));
+		writel(0, (void *)(aplic->addr + APLIC_IDC_BASE +
+			  i * APLIC_IDC_SIZE + APLIC_IDC_IFORCE));
+		writel(APLIC_DISABLE_ITHRESHOLD, (void *)(aplic->addr +
+						  APLIC_IDC_BASE +
+						  (i * APLIC_IDC_SIZE) +
+						  APLIC_IDC_ITHRESHOLD));
+	}
+
+	/* MSI configuration */
+	if (aplic->targets_mmode && aplic->has_msicfg_mmode) {
+		aplic_writel_msicfg(&aplic->msicfg_mmode,
+				(void *)(aplic->addr + APLIC_MMSICFGADDR),
+				(void *)(aplic->addr + APLIC_MMSICFGADDRH));
+	}
+	if (aplic->targets_mmode && aplic->has_msicfg_smode) {
+		aplic_writel_msicfg(&aplic->msicfg_smode,
+				(void *)(aplic->addr + APLIC_SMSICFGADDR),
+				(void *)(aplic->addr + APLIC_SMSICFGADDRH));
+	}
+
+	/*
+	 * Add APLIC region to the root domain if:
+	 * 1) It targets M-mode of any HART directly or via MSIs
+	 * 2) All interrupts are delegated to some child APLIC
+	 */
+	if (aplic->targets_mmode ||
+	    ((first_deleg_irq < last_deleg_irq) &&
+	    (last_deleg_irq == aplic->num_source) &&
+	    (first_deleg_irq == 1))) {
+		sbi_domain_memregion_init(aplic->addr, aplic->size,
+					  SBI_DOMAIN_MEMREGION_MMIO, &reg);
+		rc = sbi_domain_root_add_memregion(&reg);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
diff --git a/lib/utils/irqchip/objects.mk b/lib/utils/irqchip/objects.mk
index ae6f255..b2b3f79 100644
--- a/lib/utils/irqchip/objects.mk
+++ b/lib/utils/irqchip/objects.mk
@@ -10,5 +10,6 @@
 libsbiutils-objs-y += irqchip/fdt_irqchip.o
 libsbiutils-objs-y += irqchip/fdt_irqchip_imsic.o
 libsbiutils-objs-y += irqchip/fdt_irqchip_plic.o
+libsbiutils-objs-y += irqchip/aplic.o
 libsbiutils-objs-y += irqchip/imsic.o
 libsbiutils-objs-y += irqchip/plic.o