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1// SPDX-License-Identifier: GPL-2.02//3// Copyright (C) 2019 Texas Instruments Incorporated - https://www.ti.com/4// Author: Vignesh Raghavendra <vigneshr@ti.com>5 6#include <linux/completion.h>7#include <linux/dma-direction.h>8#include <linux/dma-mapping.h>9#include <linux/dmaengine.h>10#include <linux/err.h>11#include <linux/kernel.h>12#include <linux/module.h>13#include <linux/mtd/cfi.h>14#include <linux/mtd/hyperbus.h>15#include <linux/mtd/mtd.h>16#include <linux/mux/consumer.h>17#include <linux/of.h>18#include <linux/of_address.h>19#include <linux/platform_device.h>20#include <linux/sched/task_stack.h>21#include <linux/types.h>22 23#define AM654_HBMC_CALIB_COUNT 2524 25struct am654_hbmc_device_priv {26 struct completion rx_dma_complete;27 phys_addr_t device_base;28 struct hyperbus_ctlr *ctlr;29 struct dma_chan *rx_chan;30};31 32struct am654_hbmc_priv {33 struct hyperbus_ctlr ctlr;34 struct hyperbus_device hbdev;35 struct mux_control *mux_ctrl;36};37 38static int am654_hbmc_calibrate(struct hyperbus_device *hbdev)39{40 struct map_info *map = &hbdev->map;41 struct cfi_private cfi;42 int count = AM654_HBMC_CALIB_COUNT;43 int pass_count = 0;44 int ret;45 46 cfi.interleave = 1;47 cfi.device_type = CFI_DEVICETYPE_X16;48 cfi_send_gen_cmd(0xF0, 0, 0, map, &cfi, cfi.device_type, NULL);49 cfi_send_gen_cmd(0x98, 0x55, 0, map, &cfi, cfi.device_type, NULL);50 51 while (count--) {52 ret = cfi_qry_present(map, 0, &cfi);53 if (ret)54 pass_count++;55 else56 pass_count = 0;57 if (pass_count == 5)58 break;59 }60 61 cfi_qry_mode_off(0, map, &cfi);62 63 return ret;64}65 66static void am654_hbmc_dma_callback(void *param)67{68 struct am654_hbmc_device_priv *priv = param;69 70 complete(&priv->rx_dma_complete);71}72 73static int am654_hbmc_dma_read(struct am654_hbmc_device_priv *priv, void *to,74 unsigned long from, ssize_t len)75 76{77 enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;78 struct dma_chan *rx_chan = priv->rx_chan;79 struct dma_async_tx_descriptor *tx;80 dma_addr_t dma_dst, dma_src;81 dma_cookie_t cookie;82 int ret;83 84 if (!priv->rx_chan || !virt_addr_valid(to) || object_is_on_stack(to))85 return -EINVAL;86 87 dma_dst = dma_map_single(rx_chan->device->dev, to, len, DMA_FROM_DEVICE);88 if (dma_mapping_error(rx_chan->device->dev, dma_dst)) {89 dev_dbg(priv->ctlr->dev, "DMA mapping failed\n");90 return -EIO;91 }92 93 dma_src = priv->device_base + from;94 tx = dmaengine_prep_dma_memcpy(rx_chan, dma_dst, dma_src, len, flags);95 if (!tx) {96 dev_err(priv->ctlr->dev, "device_prep_dma_memcpy error\n");97 ret = -EIO;98 goto unmap_dma;99 }100 101 reinit_completion(&priv->rx_dma_complete);102 tx->callback = am654_hbmc_dma_callback;103 tx->callback_param = priv;104 cookie = dmaengine_submit(tx);105 106 ret = dma_submit_error(cookie);107 if (ret) {108 dev_err(priv->ctlr->dev, "dma_submit_error %d\n", cookie);109 goto unmap_dma;110 }111 112 dma_async_issue_pending(rx_chan);113 if (!wait_for_completion_timeout(&priv->rx_dma_complete, msecs_to_jiffies(len + 1000))) {114 dmaengine_terminate_sync(rx_chan);115 dev_err(priv->ctlr->dev, "DMA wait_for_completion_timeout\n");116 ret = -ETIMEDOUT;117 }118 119unmap_dma:120 dma_unmap_single(rx_chan->device->dev, dma_dst, len, DMA_FROM_DEVICE);121 return ret;122}123 124static void am654_hbmc_read(struct hyperbus_device *hbdev, void *to,125 unsigned long from, ssize_t len)126{127 struct am654_hbmc_device_priv *priv = hbdev->priv;128 129 if (len < SZ_1K || am654_hbmc_dma_read(priv, to, from, len))130 memcpy_fromio(to, hbdev->map.virt + from, len);131}132 133static const struct hyperbus_ops am654_hbmc_ops = {134 .calibrate = am654_hbmc_calibrate,135 .copy_from = am654_hbmc_read,136};137 138static int am654_hbmc_request_mmap_dma(struct am654_hbmc_device_priv *priv)139{140 struct dma_chan *rx_chan;141 dma_cap_mask_t mask;142 143 dma_cap_zero(mask);144 dma_cap_set(DMA_MEMCPY, mask);145 146 rx_chan = dma_request_chan_by_mask(&mask);147 if (IS_ERR(rx_chan)) {148 if (PTR_ERR(rx_chan) == -EPROBE_DEFER)149 return -EPROBE_DEFER;150 dev_dbg(priv->ctlr->dev, "No DMA channel available\n");151 return 0;152 }153 priv->rx_chan = rx_chan;154 init_completion(&priv->rx_dma_complete);155 156 return 0;157}158 159static int am654_hbmc_probe(struct platform_device *pdev)160{161 struct device_node *np = pdev->dev.of_node;162 struct am654_hbmc_device_priv *dev_priv;163 struct device *dev = &pdev->dev;164 struct am654_hbmc_priv *priv;165 struct resource res;166 int ret;167 168 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);169 if (!priv)170 return -ENOMEM;171 172 platform_set_drvdata(pdev, priv);173 174 priv->hbdev.np = of_get_next_child(np, NULL);175 ret = of_address_to_resource(priv->hbdev.np, 0, &res);176 if (ret)177 return ret;178 179 if (of_property_read_bool(dev->of_node, "mux-controls")) {180 struct mux_control *control = devm_mux_control_get(dev, NULL);181 182 if (IS_ERR(control))183 return PTR_ERR(control);184 185 ret = mux_control_select(control, 1);186 if (ret) {187 dev_err(dev, "Failed to select HBMC mux\n");188 return ret;189 }190 priv->mux_ctrl = control;191 }192 193 priv->hbdev.map.size = resource_size(&res);194 priv->hbdev.map.virt = devm_ioremap_resource(dev, &res);195 if (IS_ERR(priv->hbdev.map.virt))196 return PTR_ERR(priv->hbdev.map.virt);197 198 priv->ctlr.dev = dev;199 priv->ctlr.ops = &am654_hbmc_ops;200 priv->hbdev.ctlr = &priv->ctlr;201 202 dev_priv = devm_kzalloc(dev, sizeof(*dev_priv), GFP_KERNEL);203 if (!dev_priv) {204 ret = -ENOMEM;205 goto disable_mux;206 }207 208 priv->hbdev.priv = dev_priv;209 dev_priv->device_base = res.start;210 dev_priv->ctlr = &priv->ctlr;211 212 ret = am654_hbmc_request_mmap_dma(dev_priv);213 if (ret)214 goto disable_mux;215 216 ret = hyperbus_register_device(&priv->hbdev);217 if (ret) {218 dev_err(dev, "failed to register controller\n");219 goto release_dma;220 }221 222 return 0;223release_dma:224 if (dev_priv->rx_chan)225 dma_release_channel(dev_priv->rx_chan);226disable_mux:227 if (priv->mux_ctrl)228 mux_control_deselect(priv->mux_ctrl);229 return ret;230}231 232static void am654_hbmc_remove(struct platform_device *pdev)233{234 struct am654_hbmc_priv *priv = platform_get_drvdata(pdev);235 struct am654_hbmc_device_priv *dev_priv = priv->hbdev.priv;236 237 hyperbus_unregister_device(&priv->hbdev);238 239 if (priv->mux_ctrl)240 mux_control_deselect(priv->mux_ctrl);241 242 if (dev_priv->rx_chan)243 dma_release_channel(dev_priv->rx_chan);244}245 246static const struct of_device_id am654_hbmc_dt_ids[] = {247 {248 .compatible = "ti,am654-hbmc",249 },250 { /* end of table */ }251};252 253MODULE_DEVICE_TABLE(of, am654_hbmc_dt_ids);254 255static struct platform_driver am654_hbmc_platform_driver = {256 .probe = am654_hbmc_probe,257 .remove_new = am654_hbmc_remove,258 .driver = {259 .name = "hbmc-am654",260 .of_match_table = am654_hbmc_dt_ids,261 },262};263 264module_platform_driver(am654_hbmc_platform_driver);265 266MODULE_DESCRIPTION("HBMC driver for AM654 SoC");267MODULE_LICENSE("GPL v2");268MODULE_ALIAS("platform:hbmc-am654");269MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");270