[RFC,17/21] DO_NOT_MERGE soc: add Foobar SoC memory controller driver

Commit Message

Drew Fustini April 19, 2023, 11:11 a.m. UTC

Add example driver for a SoC memory controller that implements CBQRI.

Co-developed-by: Adrien Ricciardi <[e-mail]>
Signed-off-by: Adrien Ricciardi <[e-mail]>
Signed-off-by: Drew Fustini <[e-mail]>
---
 drivers/soc/foobar/foobar_cbqri_memory.c | 83 ++++++++++++++++++++++++
 1 file changed, 83 insertions(+)
 create mode 100644 drivers/soc/foobar/foobar_cbqri_memory.c

Patch

diff --git a/drivers/soc/foobar/foobar_cbqri_memory.c b/drivers/soc/foobar/foobar_cbqri_memory.c
new file mode 100644
index 000000000000..0a0c542a25e1
--- /dev/null
+++ b/drivers/soc/foobar/foobar_cbqri_memory.c
@@ -0,0 +1,83 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Foobar Systems CBQRI memory controller
+ */
+
+#define pr_fmt(fmt) "foobar-mem: " fmt
+
+#include <linux/device.h>
+#include <linux/of.h>
+#include <linux/riscv_qos.h>
+
+static const struct of_device_id foobar_cbqri_memory_ids[] = {
+	{ .compatible = "foobar,memory-controller" },
+	{ }
+};
+
+static int __init foobar_cbqri_memory_init(void)
+{
+	struct device_node *np;
+	int err;
+	u32 value;
+	struct cbqri_controller_info *ctrl_info;
+
+	for_each_matching_node(np, foobar_cbqri_memory_ids) {
+		if (!of_device_is_available(np)) {
+			of_node_put(np);
+			continue;
+		}
+
+		ctrl_info = kzalloc(sizeof(*ctrl_info), GFP_KERNEL);
+		if (!ctrl_info)
+			goto err_node_put;
+		ctrl_info->type = CBQRI_CONTROLLER_TYPE_BANDWIDTH;
+
+		err = of_property_read_u32_index(np, "reg", 1, &value);
+		if (err) {
+			pr_err("Failed to read reg base address (%d)", err);
+			goto err_kfree_ctrl_info;
+		}
+		ctrl_info->addr = value;
+
+		err = of_property_read_u32_index(np, "reg", 3, &value);
+		if (err) {
+			pr_err("Failed to read reg size (%d)", err);
+			goto err_kfree_ctrl_info;
+		}
+		ctrl_info->size = value;
+
+		err = of_property_read_u32(np, "riscv,cbqri-rcid", &value);
+		if (err) {
+			pr_err("Failed to read RCID count (%d)", err);
+			goto err_kfree_ctrl_info;
+		}
+		ctrl_info->rcid_count = value;
+
+		err = of_property_read_u32(np, "riscv,cbqri-mcid", &value);
+		if (err) {
+			pr_err("Failed to read MCID count (%d)", err);
+			goto err_kfree_ctrl_info;
+		}
+		ctrl_info->mcid_count = value;
+
+		of_node_put(np);
+
+		pr_debug("addr=0x%lx max-rcid=%u max-mcid=%u", ctrl_info->addr,
+			 ctrl_info->rcid_count, ctrl_info->mcid_count);
+
+		/* Fill the list shared with RISC-V QoS resctrl */
+		INIT_LIST_HEAD(&ctrl_info->list);
+		list_add_tail(&ctrl_info->list, &cbqri_controllers);
+	}
+
+	return 0;
+
+err_kfree_ctrl_info:
+	kfree(ctrl_info);
+
+err_node_put:
+	of_node_put(np);
+
+	return err;
+}
+device_initcall(foobar_cbqri_memory_init);