diff options
Diffstat (limited to 'drivers/mtd/hyperbus/rpc-if.c')
| -rw-r--r-- | drivers/mtd/hyperbus/rpc-if.c | 179 |
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"); |