| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (c) 2016-2017, Linaro Ltd |
| */ |
| |
| #include <linux/idr.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/list.h> |
| #include <linux/mfd/syscon.h> |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/of_address.h> |
| #include <linux/of_irq.h> |
| #include <linux/platform_device.h> |
| #include <linux/regmap.h> |
| #include <linux/rpmsg.h> |
| #include <linux/slab.h> |
| #include <linux/workqueue.h> |
| #include <linux/mailbox_client.h> |
| |
| #include "rpmsg_internal.h" |
| #include "qcom_glink_native.h" |
| |
| #define RPM_TOC_SIZE 256 |
| #define RPM_TOC_MAGIC 0x67727430 /* grt0 */ |
| #define RPM_TOC_MAX_ENTRIES ((RPM_TOC_SIZE - sizeof(struct rpm_toc)) / \ |
| sizeof(struct rpm_toc_entry)) |
| |
| #define RPM_TX_FIFO_ID 0x61703272 /* ap2r */ |
| #define RPM_RX_FIFO_ID 0x72326170 /* r2ap */ |
| |
| #define to_rpm_pipe(p) container_of(p, struct glink_rpm_pipe, native) |
| |
| struct rpm_toc_entry { |
| __le32 id; |
| __le32 offset; |
| __le32 size; |
| } __packed; |
| |
| struct rpm_toc { |
| __le32 magic; |
| __le32 count; |
| |
| struct rpm_toc_entry entries[]; |
| } __packed; |
| |
| struct glink_rpm_pipe { |
| struct qcom_glink_pipe native; |
| |
| void __iomem *tail; |
| void __iomem *head; |
| |
| void __iomem *fifo; |
| }; |
| |
| struct glink_rpm { |
| struct qcom_glink *glink; |
| |
| int irq; |
| |
| struct mbox_client mbox_client; |
| struct mbox_chan *mbox_chan; |
| |
| struct glink_rpm_pipe rx_pipe; |
| struct glink_rpm_pipe tx_pipe; |
| }; |
| |
| static size_t glink_rpm_rx_avail(struct qcom_glink_pipe *glink_pipe) |
| { |
| struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); |
| unsigned int head; |
| unsigned int tail; |
| |
| head = readl(pipe->head); |
| tail = readl(pipe->tail); |
| |
| if (head < tail) |
| return pipe->native.length - tail + head; |
| else |
| return head - tail; |
| } |
| |
| static void glink_rpm_rx_peek(struct qcom_glink_pipe *glink_pipe, |
| void *data, unsigned int offset, size_t count) |
| { |
| struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); |
| unsigned int tail; |
| size_t len; |
| |
| tail = readl(pipe->tail); |
| tail += offset; |
| if (tail >= pipe->native.length) |
| tail -= pipe->native.length; |
| |
| len = min_t(size_t, count, pipe->native.length - tail); |
| if (len) { |
| __ioread32_copy(data, pipe->fifo + tail, |
| len / sizeof(u32)); |
| } |
| |
| if (len != count) { |
| __ioread32_copy(data + len, pipe->fifo, |
| (count - len) / sizeof(u32)); |
| } |
| } |
| |
| static void glink_rpm_rx_advance(struct qcom_glink_pipe *glink_pipe, |
| size_t count) |
| { |
| struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); |
| unsigned int tail; |
| |
| tail = readl(pipe->tail); |
| |
| tail += count; |
| if (tail >= pipe->native.length) |
| tail -= pipe->native.length; |
| |
| writel(tail, pipe->tail); |
| } |
| |
| static size_t glink_rpm_tx_avail(struct qcom_glink_pipe *glink_pipe) |
| { |
| struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); |
| unsigned int head; |
| unsigned int tail; |
| |
| head = readl(pipe->head); |
| tail = readl(pipe->tail); |
| |
| if (tail <= head) |
| return pipe->native.length - head + tail; |
| else |
| return tail - head; |
| } |
| |
| static unsigned int glink_rpm_tx_write_one(struct glink_rpm_pipe *pipe, |
| unsigned int head, |
| const void *data, size_t count) |
| { |
| size_t len; |
| |
| len = min_t(size_t, count, pipe->native.length - head); |
| if (len) { |
| __iowrite32_copy(pipe->fifo + head, data, |
| len / sizeof(u32)); |
| } |
| |
| if (len != count) { |
| __iowrite32_copy(pipe->fifo, data + len, |
| (count - len) / sizeof(u32)); |
| } |
| |
| head += count; |
| if (head >= pipe->native.length) |
| head -= pipe->native.length; |
| |
| return head; |
| } |
| |
| static void glink_rpm_tx_write(struct qcom_glink_pipe *glink_pipe, |
| const void *hdr, size_t hlen, |
| const void *data, size_t dlen) |
| { |
| struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); |
| size_t tlen = hlen + dlen; |
| size_t aligned_dlen; |
| unsigned int head; |
| char padding[8] = {0}; |
| size_t pad; |
| |
| /* Header length comes from glink native and is always 4 byte aligned */ |
| if (WARN(hlen % 4, "Glink Header length must be 4 bytes aligned\n")) |
| return; |
| |
| /* |
| * Move the unaligned tail of the message to the padding chunk, to |
| * ensure word aligned accesses |
| */ |
| aligned_dlen = ALIGN_DOWN(dlen, 4); |
| if (aligned_dlen != dlen) |
| memcpy(padding, data + aligned_dlen, dlen - aligned_dlen); |
| |
| head = readl(pipe->head); |
| head = glink_rpm_tx_write_one(pipe, head, hdr, hlen); |
| head = glink_rpm_tx_write_one(pipe, head, data, aligned_dlen); |
| |
| pad = ALIGN(tlen, 8) - ALIGN_DOWN(tlen, 4); |
| if (pad) |
| head = glink_rpm_tx_write_one(pipe, head, padding, pad); |
| writel(head, pipe->head); |
| } |
| |
| static void glink_rpm_tx_kick(struct qcom_glink_pipe *glink_pipe) |
| { |
| struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe); |
| struct glink_rpm *rpm = container_of(pipe, struct glink_rpm, tx_pipe); |
| |
| mbox_send_message(rpm->mbox_chan, NULL); |
| mbox_client_txdone(rpm->mbox_chan, 0); |
| } |
| |
| static irqreturn_t qcom_glink_rpm_intr(int irq, void *data) |
| { |
| struct glink_rpm *rpm = data; |
| |
| qcom_glink_native_rx(rpm->glink); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int glink_rpm_parse_toc(struct device *dev, |
| void __iomem *msg_ram, |
| size_t msg_ram_size, |
| struct glink_rpm_pipe *rx, |
| struct glink_rpm_pipe *tx) |
| { |
| struct rpm_toc *toc; |
| int num_entries; |
| unsigned int id; |
| size_t offset; |
| size_t size; |
| void *buf; |
| int i; |
| |
| buf = kzalloc(RPM_TOC_SIZE, GFP_KERNEL); |
| if (!buf) |
| return -ENOMEM; |
| |
| __ioread32_copy(buf, msg_ram + msg_ram_size - RPM_TOC_SIZE, |
| RPM_TOC_SIZE / sizeof(u32)); |
| |
| toc = buf; |
| |
| if (le32_to_cpu(toc->magic) != RPM_TOC_MAGIC) { |
| dev_err(dev, "RPM TOC has invalid magic\n"); |
| goto err_inval; |
| } |
| |
| num_entries = le32_to_cpu(toc->count); |
| if (num_entries > RPM_TOC_MAX_ENTRIES) { |
| dev_err(dev, "Invalid number of toc entries\n"); |
| goto err_inval; |
| } |
| |
| for (i = 0; i < num_entries; i++) { |
| id = le32_to_cpu(toc->entries[i].id); |
| offset = le32_to_cpu(toc->entries[i].offset); |
| size = le32_to_cpu(toc->entries[i].size); |
| |
| if (offset > msg_ram_size || offset + size > msg_ram_size) { |
| dev_err(dev, "TOC entry with invalid size\n"); |
| continue; |
| } |
| |
| switch (id) { |
| case RPM_RX_FIFO_ID: |
| rx->native.length = size; |
| |
| rx->tail = msg_ram + offset; |
| rx->head = msg_ram + offset + sizeof(u32); |
| rx->fifo = msg_ram + offset + 2 * sizeof(u32); |
| break; |
| case RPM_TX_FIFO_ID: |
| tx->native.length = size; |
| |
| tx->tail = msg_ram + offset; |
| tx->head = msg_ram + offset + sizeof(u32); |
| tx->fifo = msg_ram + offset + 2 * sizeof(u32); |
| break; |
| } |
| } |
| |
| if (!rx->fifo || !tx->fifo) { |
| dev_err(dev, "Unable to find rx and tx descriptors\n"); |
| goto err_inval; |
| } |
| |
| kfree(buf); |
| return 0; |
| |
| err_inval: |
| kfree(buf); |
| return -EINVAL; |
| } |
| |
| static int glink_rpm_probe(struct platform_device *pdev) |
| { |
| struct qcom_glink *glink; |
| struct glink_rpm *rpm; |
| struct device_node *np; |
| void __iomem *msg_ram; |
| size_t msg_ram_size; |
| struct device *dev = &pdev->dev; |
| struct resource r; |
| int ret; |
| |
| rpm = devm_kzalloc(&pdev->dev, sizeof(*rpm), GFP_KERNEL); |
| if (!rpm) |
| return -ENOMEM; |
| |
| np = of_parse_phandle(dev->of_node, "qcom,rpm-msg-ram", 0); |
| ret = of_address_to_resource(np, 0, &r); |
| of_node_put(np); |
| if (ret) |
| return ret; |
| |
| msg_ram = devm_ioremap(dev, r.start, resource_size(&r)); |
| msg_ram_size = resource_size(&r); |
| if (!msg_ram) |
| return -ENOMEM; |
| |
| ret = glink_rpm_parse_toc(dev, msg_ram, msg_ram_size, |
| &rpm->rx_pipe, &rpm->tx_pipe); |
| if (ret) |
| return ret; |
| |
| rpm->irq = of_irq_get(dev->of_node, 0); |
| ret = devm_request_irq(dev, rpm->irq, qcom_glink_rpm_intr, |
| IRQF_NO_SUSPEND | IRQF_NO_AUTOEN, |
| "glink-rpm", rpm); |
| if (ret) { |
| dev_err(dev, "failed to request IRQ\n"); |
| return ret; |
| } |
| |
| rpm->mbox_client.dev = dev; |
| rpm->mbox_client.knows_txdone = true; |
| rpm->mbox_chan = mbox_request_channel(&rpm->mbox_client, 0); |
| if (IS_ERR(rpm->mbox_chan)) |
| return dev_err_probe(dev, PTR_ERR(rpm->mbox_chan), "failed to acquire IPC channel\n"); |
| |
| /* Pipe specific accessors */ |
| rpm->rx_pipe.native.avail = glink_rpm_rx_avail; |
| rpm->rx_pipe.native.peek = glink_rpm_rx_peek; |
| rpm->rx_pipe.native.advance = glink_rpm_rx_advance; |
| rpm->tx_pipe.native.avail = glink_rpm_tx_avail; |
| rpm->tx_pipe.native.write = glink_rpm_tx_write; |
| rpm->tx_pipe.native.kick = glink_rpm_tx_kick; |
| |
| writel(0, rpm->tx_pipe.head); |
| writel(0, rpm->rx_pipe.tail); |
| |
| glink = qcom_glink_native_probe(dev, |
| 0, |
| &rpm->rx_pipe.native, |
| &rpm->tx_pipe.native, |
| true); |
| if (IS_ERR(glink)) { |
| mbox_free_channel(rpm->mbox_chan); |
| return PTR_ERR(glink); |
| } |
| |
| rpm->glink = glink; |
| |
| platform_set_drvdata(pdev, rpm); |
| |
| enable_irq(rpm->irq); |
| |
| return 0; |
| } |
| |
| static void glink_rpm_remove(struct platform_device *pdev) |
| { |
| struct glink_rpm *rpm = platform_get_drvdata(pdev); |
| struct qcom_glink *glink = rpm->glink; |
| |
| disable_irq(rpm->irq); |
| |
| qcom_glink_native_remove(glink); |
| |
| mbox_free_channel(rpm->mbox_chan); |
| } |
| |
| static const struct of_device_id glink_rpm_of_match[] = { |
| { .compatible = "qcom,glink-rpm" }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(of, glink_rpm_of_match); |
| |
| static struct platform_driver glink_rpm_driver = { |
| .probe = glink_rpm_probe, |
| .remove_new = glink_rpm_remove, |
| .driver = { |
| .name = "qcom_glink_rpm", |
| .of_match_table = glink_rpm_of_match, |
| }, |
| }; |
| |
| static int __init glink_rpm_init(void) |
| { |
| return platform_driver_register(&glink_rpm_driver); |
| } |
| subsys_initcall(glink_rpm_init); |
| |
| static void __exit glink_rpm_exit(void) |
| { |
| platform_driver_unregister(&glink_rpm_driver); |
| } |
| module_exit(glink_rpm_exit); |
| |
| MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@linaro.org>"); |
| MODULE_DESCRIPTION("Qualcomm GLINK RPM driver"); |
| MODULE_LICENSE("GPL v2"); |