summaryrefslogtreecommitdiffstats
path: root/drivers/mtd/hyperbus/rpc-if.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/mtd/hyperbus/rpc-if.c')
-rw-r--r--drivers/mtd/hyperbus/rpc-if.c179
1 files changed, 179 insertions, 0 deletions
diff --git a/drivers/mtd/hyperbus/rpc-if.c b/drivers/mtd/hyperbus/rpc-if.c
new file mode 100644
index 000000000..d00d30243
--- /dev/null
+++ b/drivers/mtd/hyperbus/rpc-if.c
@@ -0,0 +1,179 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Linux driver for RPC-IF HyperFlash
+ *
+ * Copyright (C) 2019-2020 Cogent Embedded, Inc.
+ */
+
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mtd/hyperbus.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mux/consumer.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+
+#include <memory/renesas-rpc-if.h>
+
+struct rpcif_hyperbus {
+ struct rpcif rpc;
+ struct hyperbus_ctlr ctlr;
+ struct hyperbus_device hbdev;
+};
+
+static const struct rpcif_op rpcif_op_tmpl = {
+ .cmd = {
+ .buswidth = 8,
+ .ddr = true,
+ },
+ .ocmd = {
+ .buswidth = 8,
+ .ddr = true,
+ },
+ .addr = {
+ .nbytes = 1,
+ .buswidth = 8,
+ .ddr = true,
+ },
+ .data = {
+ .buswidth = 8,
+ .ddr = true,
+ },
+};
+
+static void rpcif_hb_prepare_read(struct rpcif *rpc, void *to,
+ unsigned long from, ssize_t len)
+{
+ struct rpcif_op op = rpcif_op_tmpl;
+
+ op.cmd.opcode = HYPERBUS_RW_READ | HYPERBUS_AS_MEM;
+ op.addr.val = from >> 1;
+ op.dummy.buswidth = 1;
+ op.dummy.ncycles = 15;
+ op.data.dir = RPCIF_DATA_IN;
+ op.data.nbytes = len;
+ op.data.buf.in = to;
+
+ rpcif_prepare(rpc, &op, NULL, NULL);
+}
+
+static void rpcif_hb_prepare_write(struct rpcif *rpc, unsigned long to,
+ void *from, ssize_t len)
+{
+ struct rpcif_op op = rpcif_op_tmpl;
+
+ op.cmd.opcode = HYPERBUS_RW_WRITE | HYPERBUS_AS_MEM;
+ op.addr.val = to >> 1;
+ op.data.dir = RPCIF_DATA_OUT;
+ op.data.nbytes = len;
+ op.data.buf.out = from;
+
+ rpcif_prepare(rpc, &op, NULL, NULL);
+}
+
+static u16 rpcif_hb_read16(struct hyperbus_device *hbdev, unsigned long addr)
+{
+ struct rpcif_hyperbus *hyperbus =
+ container_of(hbdev, struct rpcif_hyperbus, hbdev);
+ map_word data;
+
+ rpcif_hb_prepare_read(&hyperbus->rpc, &data, addr, 2);
+
+ rpcif_manual_xfer(&hyperbus->rpc);
+
+ return data.x[0];
+}
+
+static void rpcif_hb_write16(struct hyperbus_device *hbdev, unsigned long addr,
+ u16 data)
+{
+ struct rpcif_hyperbus *hyperbus =
+ container_of(hbdev, struct rpcif_hyperbus, hbdev);
+
+ rpcif_hb_prepare_write(&hyperbus->rpc, addr, &data, 2);
+
+ rpcif_manual_xfer(&hyperbus->rpc);
+}
+
+static void rpcif_hb_copy_from(struct hyperbus_device *hbdev, void *to,
+ unsigned long from, ssize_t len)
+{
+ struct rpcif_hyperbus *hyperbus =
+ container_of(hbdev, struct rpcif_hyperbus, hbdev);
+
+ rpcif_hb_prepare_read(&hyperbus->rpc, to, from, len);
+
+ rpcif_dirmap_read(&hyperbus->rpc, from, len, to);
+}
+
+static const struct hyperbus_ops rpcif_hb_ops = {
+ .read16 = rpcif_hb_read16,
+ .write16 = rpcif_hb_write16,
+ .copy_from = rpcif_hb_copy_from,
+};
+
+static int rpcif_hb_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct rpcif_hyperbus *hyperbus;
+ int error;
+
+ hyperbus = devm_kzalloc(dev, sizeof(*hyperbus), GFP_KERNEL);
+ if (!hyperbus)
+ return -ENOMEM;
+
+ error = rpcif_sw_init(&hyperbus->rpc, pdev->dev.parent);
+ if (error)
+ return error;
+
+ platform_set_drvdata(pdev, hyperbus);
+
+ rpcif_enable_rpm(&hyperbus->rpc);
+
+ error = rpcif_hw_init(&hyperbus->rpc, true);
+ if (error)
+ goto out_disable_rpm;
+
+ hyperbus->hbdev.map.size = hyperbus->rpc.size;
+ hyperbus->hbdev.map.virt = hyperbus->rpc.dirmap;
+
+ hyperbus->ctlr.dev = dev;
+ hyperbus->ctlr.ops = &rpcif_hb_ops;
+ hyperbus->hbdev.ctlr = &hyperbus->ctlr;
+ hyperbus->hbdev.np = of_get_next_child(pdev->dev.parent->of_node, NULL);
+ error = hyperbus_register_device(&hyperbus->hbdev);
+ if (error)
+ goto out_disable_rpm;
+
+ return 0;
+
+out_disable_rpm:
+ rpcif_disable_rpm(&hyperbus->rpc);
+ return error;
+}
+
+static int rpcif_hb_remove(struct platform_device *pdev)
+{
+ struct rpcif_hyperbus *hyperbus = platform_get_drvdata(pdev);
+
+ hyperbus_unregister_device(&hyperbus->hbdev);
+
+ rpcif_disable_rpm(&hyperbus->rpc);
+
+ return 0;
+}
+
+static struct platform_driver rpcif_platform_driver = {
+ .probe = rpcif_hb_probe,
+ .remove = rpcif_hb_remove,
+ .driver = {
+ .name = "rpc-if-hyperflash",
+ },
+};
+
+module_platform_driver(rpcif_platform_driver);
+
+MODULE_DESCRIPTION("Renesas RPC-IF HyperFlash driver");
+MODULE_LICENSE("GPL v2");