platform: Move platform common to lib/utils.

Currently, platform/common contains platform/non-platform specific
common minimal drivers and libraries. This is helpful is all platforms
are built within opensbi framework.

Move them to lib/utils so that any external platform code also can
reuse the minimalistic drivers or other common libraries.

This patch doesn't introduce any functional changes.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Acked-by: Anup Patel <anup.patel@wdc.com>

2 files changed, 130 insertions, 0 deletions

diff --git a/lib/utils/irqchip/objects.mk b/lib/utils/irqchip/objects.mk
new file mode 100644
index 0000000..fa7c937
--- /dev/null
+++ b/lib/utils/irqchip/objects.mk
@@ -0,0 +1,10 @@
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2019 Western Digital Corporation or its affiliates.
+#
+# Authors:
+#   Anup Patel <anup.patel@wdc.com>
+#
+
+libsbiutils-objs-$(PLATFORM_IRQCHIP_PLIC) += irqchip/plic.o
diff --git a/lib/utils/irqchip/plic.c b/lib/utils/irqchip/plic.c
new file mode 100644
index 0000000..2131707
--- /dev/null
+++ b/lib/utils/irqchip/plic.c
@@ -0,0 +1,120 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2019 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ */
+
+#include <sbi/riscv_io.h>
+#include <sbi/riscv_encoding.h>
+#include <sbi/sbi_console.h>
+#include <sbi/string.h>
+#include <sbi_utils/tinyfdt.h>
+#include <sbi_utils/irqchip/plic.h>
+
+#define PLIC_PRIORITY_BASE 0x0
+#define PLIC_PENDING_BASE 0x1000
+#define PLIC_ENABLE_BASE 0x2000
+#define PLIC_ENABLE_STRIDE 0x80
+#define PLIC_CONTEXT_BASE 0x200000
+#define PLIC_CONTEXT_STRIDE 0x1000
+
+static u32 plic_hart_count;
+static u32 plic_num_sources;
+static volatile void *plic_base;
+
+static void plic_set_priority(u32 source, u32 val)
+{
+	volatile void *plic_priority =
+		plic_base + PLIC_PRIORITY_BASE + 4 * source;
+	writel(val, plic_priority);
+}
+
+static void plic_set_thresh(u32 cntxid, u32 val)
+{
+	volatile void *plic_thresh =
+		plic_base + PLIC_CONTEXT_BASE + PLIC_CONTEXT_STRIDE * cntxid;
+	writel(val, plic_thresh);
+}
+
+static void plic_set_ie(u32 cntxid, u32 word_index, u32 val)
+{
+	volatile void *plic_ie =
+		plic_base + PLIC_ENABLE_BASE + PLIC_ENABLE_STRIDE * cntxid;
+	writel(val, plic_ie + word_index * 4);
+}
+
+static void plic_fdt_fixup_prop(const struct fdt_node *node,
+				const struct fdt_prop *prop, void *priv)
+{
+	u32 *cells;
+	u32 i, cells_count;
+
+	if (!prop)
+		return;
+	if (strcmp(prop->name, "interrupts-extended"))
+		return;
+
+	cells	    = prop->value;
+	cells_count = prop->len / sizeof(u32);
+
+	if (!cells_count)
+		return;
+
+	for (i = 0; i < (cells_count / 2); i++) {
+		if (fdt_rev32(cells[2 * i + 1]) == IRQ_M_EXT)
+			cells[2 * i + 1] = fdt_rev32(0xffffffff);
+	}
+}
+
+void plic_fdt_fixup(void *fdt, const char *compat)
+{
+	fdt_compat_node_prop(fdt, compat, plic_fdt_fixup_prop, NULL);
+}
+
+int plic_warm_irqchip_init(u32 target_hart, int m_cntx_id, int s_cntx_id)
+{
+	size_t i, ie_words = plic_num_sources / 32 + 1;
+
+	if (plic_hart_count <= target_hart)
+		return -1;
+
+	/* By default, disable all IRQs for M-mode of target HART */
+	if (m_cntx_id > -1) {
+		for (i = 0; i < ie_words; i++)
+			plic_set_ie(m_cntx_id, i, 0);
+	}
+
+	/* By default, disable all IRQs for S-mode of target HART */
+	if (s_cntx_id > -1) {
+		for (i = 0; i < ie_words; i++)
+			plic_set_ie(s_cntx_id, i, 0);
+	}
+
+	/* By default, enable M-mode threshold */
+	if (m_cntx_id > -1)
+		plic_set_thresh(m_cntx_id, 1);
+
+	/* By default, disable S-mode threshold */
+	if (s_cntx_id > -1)
+		plic_set_thresh(s_cntx_id, 0);
+
+	return 0;
+}
+
+int plic_cold_irqchip_init(unsigned long base, u32 num_sources, u32 hart_count)
+{
+	int i;
+
+	plic_hart_count	 = hart_count;
+	plic_num_sources = num_sources;
+	plic_base	 = (void *)base;
+
+	/* Configure default priorities of all IRQs */
+	for (i = 1; i <= plic_num_sources; i++)
+		plic_set_priority(i, 1);
+
+	return 0;
+}