--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (c) 2019 MediaTek Inc.
+
+#include <asm/barrier.h>
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/platform_device.h>
+#include <linux/remoteproc.h>
+#include <linux/remoteproc/mtk_scp.h>
+
+#include "mtk_common.h"
+#include "remoteproc_internal.h"
+
+#define MAX_CODE_SIZE 0x500000
+#define SCP_FW_END 0x7C000
+
+/**
+ * scp_get() - get a reference to SCP.
+ *
+ * @pdev: the platform device of the module requesting SCP platform
+ * device for using SCP API.
+ *
+ * Return: Return NULL if failed. otherwise reference to SCP.
+ **/
+struct mtk_scp *scp_get(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *scp_node;
+ struct platform_device *scp_pdev;
+
+ scp_node = of_parse_phandle(dev->of_node, "mediatek,scp", 0);
+ if (!scp_node) {
+ dev_err(dev, "can't get SCP node\n");
+ return NULL;
+ }
+
+ scp_pdev = of_find_device_by_node(scp_node);
+ of_node_put(scp_node);
+
+ if (WARN_ON(!scp_pdev)) {
+ dev_err(dev, "SCP pdev failed\n");
+ return NULL;
+ }
+
+ return platform_get_drvdata(scp_pdev);
+}
+EXPORT_SYMBOL_GPL(scp_get);
+
+/**
+ * scp_put() - "free" the SCP
+ *
+ * @scp: mtk_scp structure from scp_get().
+ **/
+void scp_put(struct mtk_scp *scp)
+{
+ put_device(scp->dev);
+}
+EXPORT_SYMBOL_GPL(scp_put);
+
+static void scp_wdt_handler(struct mtk_scp *scp, u32 scp_to_host)
+{
+ dev_err(scp->dev, "SCP watchdog timeout! 0x%x", scp_to_host);
+ rproc_report_crash(scp->rproc, RPROC_WATCHDOG);
+}
+
+static void scp_init_ipi_handler(void *data, unsigned int len, void *priv)
+{
+ struct mtk_scp *scp = (struct mtk_scp *)priv;
+ struct scp_run *run = (struct scp_run *)data;
+
+ scp->run.signaled = run->signaled;
+ strscpy(scp->run.fw_ver, run->fw_ver, SCP_FW_VER_LEN);
+ scp->run.dec_capability = run->dec_capability;
+ scp->run.enc_capability = run->enc_capability;
+ wake_up_interruptible(&scp->run.wq);
+}
+
+static void scp_ipi_handler(struct mtk_scp *scp)
+{
+ struct mtk_share_obj __iomem *rcv_obj = scp->recv_buf;
+ struct scp_ipi_desc *ipi_desc = scp->ipi_desc;
+ u8 tmp_data[SCP_SHARE_BUFFER_SIZE];
+ scp_ipi_handler_t handler;
+ u32 id = readl(&rcv_obj->id);
+ u32 len = readl(&rcv_obj->len);
+
+ if (len > SCP_SHARE_BUFFER_SIZE) {
+ dev_err(scp->dev, "ipi message too long (len %d, max %d)", len,
+ SCP_SHARE_BUFFER_SIZE);
+ return;
+ }
+ if (id >= SCP_IPI_MAX) {
+ dev_err(scp->dev, "No such ipi id = %d\n", id);
+ return;
+ }
+
+ scp_ipi_lock(scp, id);
+ handler = ipi_desc[id].handler;
+ if (!handler) {
+ dev_err(scp->dev, "No such ipi id = %d\n", id);
+ scp_ipi_unlock(scp, id);
+ return;
+ }
+
+ memcpy_fromio(tmp_data, &rcv_obj->share_buf, len);
+ handler(tmp_data, len, ipi_desc[id].priv);
+ scp_ipi_unlock(scp, id);
+
+ scp->ipi_id_ack[id] = true;
+ wake_up(&scp->ack_wq);
+}
+
+static int scp_ipi_init(struct mtk_scp *scp)
+{
+ size_t send_offset = SCP_FW_END - sizeof(struct mtk_share_obj);
+ size_t recv_offset = send_offset - sizeof(struct mtk_share_obj);
+
+ /* Disable SCP to host interrupt */
+ writel(MT8183_SCP_IPC_INT_BIT, scp->reg_base + MT8183_SCP_TO_HOST);
+
+ /* shared buffer initialization */
+ scp->recv_buf =
+ (struct mtk_share_obj __iomem *)(scp->sram_base + recv_offset);
+ scp->send_buf =
+ (struct mtk_share_obj __iomem *)(scp->sram_base + send_offset);
+ memset_io(scp->recv_buf, 0, sizeof(scp->recv_buf));
+ memset_io(scp->send_buf, 0, sizeof(scp->send_buf));
+
+ return 0;
+}
+
+static void scp_reset_assert(const struct mtk_scp *scp)
+{
+ u32 val;
+
+ val = readl(scp->reg_base + MT8183_SW_RSTN);
+ val &= ~MT8183_SW_RSTN_BIT;
+ writel(val, scp->reg_base + MT8183_SW_RSTN);
+}
+
+static void scp_reset_deassert(const struct mtk_scp *scp)
+{
+ u32 val;
+
+ val = readl(scp->reg_base + MT8183_SW_RSTN);
+ val |= MT8183_SW_RSTN_BIT;
+ writel(val, scp->reg_base + MT8183_SW_RSTN);
+}
+
+static irqreturn_t scp_irq_handler(int irq, void *priv)
+{
+ struct mtk_scp *scp = priv;
+ u32 scp_to_host;
+ int ret;
+
+ ret = clk_prepare_enable(scp->clk);
+ if (ret) {
+ dev_err(scp->dev, "failed to enable clocks\n");
+ return IRQ_NONE;
+ }
+
+ scp_to_host = readl(scp->reg_base + MT8183_SCP_TO_HOST);
+ if (scp_to_host & MT8183_SCP_IPC_INT_BIT)
+ scp_ipi_handler(scp);
+ else
+ scp_wdt_handler(scp, scp_to_host);
+
+ /* SCP won't send another interrupt until we set SCP_TO_HOST to 0. */
+ writel(MT8183_SCP_IPC_INT_BIT | MT8183_SCP_WDT_INT_BIT,
+ scp->reg_base + MT8183_SCP_TO_HOST);
+ clk_disable_unprepare(scp->clk);
+
+ return IRQ_HANDLED;
+}
+
+static int scp_elf_load_segments(struct rproc *rproc, const struct firmware *fw)
+{
+ struct device *dev = &rproc->dev;
+ struct elf32_hdr *ehdr;
+ struct elf32_phdr *phdr;
+ int i, ret = 0;
+ const u8 *elf_data = fw->data;
+
+ ehdr = (struct elf32_hdr *)elf_data;
+ phdr = (struct elf32_phdr *)(elf_data + ehdr->e_phoff);
+
+ /* go through the available ELF segments */
+ for (i = 0; i < ehdr->e_phnum; i++, phdr++) {
+ u32 da = phdr->p_paddr;
+ u32 memsz = phdr->p_memsz;
+ u32 filesz = phdr->p_filesz;
+ u32 offset = phdr->p_offset;
+ void __iomem *ptr;
+
+ if (phdr->p_type != PT_LOAD)
+ continue;
+
+ dev_dbg(dev, "phdr: type %d da 0x%x memsz 0x%x filesz 0x%x\n",
+ phdr->p_type, da, memsz, filesz);
+
+ if (filesz > memsz) {
+ dev_err(dev, "bad phdr filesz 0x%x memsz 0x%x\n",
+ filesz, memsz);
+ ret = -EINVAL;
+ break;
+ }
+
+ if (offset + filesz > fw->size) {
+ dev_err(dev, "truncated fw: need 0x%x avail 0x%zx\n",
+ offset + filesz, fw->size);
+ ret = -EINVAL;
+ break;
+ }
+
+ /* grab the kernel address for this device address */
+ ptr = (void __iomem *)rproc_da_to_va(rproc, da, memsz);
+ if (!ptr) {
+ dev_err(dev, "bad phdr da 0x%x mem 0x%x\n", da, memsz);
+ ret = -EINVAL;
+ break;
+ }
+
+ /* put the segment where the remote processor expects it */
+ if (phdr->p_filesz)
+ scp_memcpy_aligned(ptr, elf_data + phdr->p_offset,
+ filesz);
+ }
+
+ return ret;
+}
+
+static int scp_load(struct rproc *rproc, const struct firmware *fw)
+{
+ const struct mtk_scp *scp = rproc->priv;
+ struct device *dev = scp->dev;
+ int ret;
+
+ ret = clk_prepare_enable(scp->clk);
+ if (ret) {
+ dev_err(dev, "failed to enable clocks\n");
+ return ret;
+ }
+
+ /* Hold SCP in reset while loading FW. */
+ scp_reset_assert(scp);
+
+ /* Reset clocks before loading FW */
+ writel(0x0, scp->reg_base + MT8183_SCP_CLK_SW_SEL);
+ writel(0x0, scp->reg_base + MT8183_SCP_CLK_DIV_SEL);
+
+ /* Initialize TCM before loading FW. */
+ writel(0x0, scp->reg_base + MT8183_SCP_L1_SRAM_PD);
+ writel(0x0, scp->reg_base + MT8183_SCP_TCM_TAIL_SRAM_PD);
+
+ /* Turn on the power of SCP's SRAM before using it. */
+ writel(0x0, scp->reg_base + MT8183_SCP_SRAM_PDN);
+
+ /*
+ * Set I-cache and D-cache size before loading SCP FW.
+ * SCP SRAM logical address may change when cache size setting differs.
+ */
+ writel(MT8183_SCP_CACHE_CON_WAYEN | MT8183_SCP_CACHESIZE_8KB,
+ scp->reg_base + MT8183_SCP_CACHE_CON);
+ writel(MT8183_SCP_CACHESIZE_8KB, scp->reg_base + MT8183_SCP_DCACHE_CON);
+
+ ret = scp_elf_load_segments(rproc, fw);
+ clk_disable_unprepare(scp->clk);
+
+ return ret;
+}
+
+static int scp_start(struct rproc *rproc)
+{
+ struct mtk_scp *scp = (struct mtk_scp *)rproc->priv;
+ struct device *dev = scp->dev;
+ struct scp_run *run = &scp->run;
+ int ret;
+
+ ret = clk_prepare_enable(scp->clk);
+ if (ret) {
+ dev_err(dev, "failed to enable clocks\n");
+ return ret;
+ }
+
+ run->signaled = false;
+
+ scp_reset_deassert(scp);
+
+ ret = wait_event_interruptible_timeout(
+ run->wq,
+ run->signaled,
+ msecs_to_jiffies(2000));
+
+ if (ret == 0) {
+ dev_err(dev, "wait SCP initialization timeout!\n");
+ ret = -ETIME;
+ goto stop;
+ }
+ if (ret == -ERESTARTSYS) {
+ dev_err(dev, "wait SCP interrupted by a signal!\n");
+ goto stop;
+ }
+ clk_disable_unprepare(scp->clk);
+ dev_info(dev, "SCP is ready. FW version %s\n", run->fw_ver);
+
+ return 0;
+
+stop:
+ scp_reset_assert(scp);
+ clk_disable_unprepare(scp->clk);
+ return ret;
+}
+
+static void *scp_da_to_va(struct rproc *rproc, u64 da, int len)
+{
+ struct mtk_scp *scp = (struct mtk_scp *)rproc->priv;
+ int offset;
+
+ if (da < scp->sram_size) {
+ offset = da;
+ if (offset >= 0 && (offset + len) < scp->sram_size)
+ return (void __force *)scp->sram_base + offset;
+ } else {
+ offset = da - scp->phys_addr;
+ if (offset >= 0 && (offset + len) < scp->dram_size)
+ return (void __force *)scp->cpu_addr + offset;
+ }
+
+ return NULL;
+}
+
+static int scp_stop(struct rproc *rproc)
+{
+ struct mtk_scp *scp = (struct mtk_scp *)rproc->priv;
+ int ret;
+
+ ret = clk_prepare_enable(scp->clk);
+ if (ret) {
+ dev_err(scp->dev, "failed to enable clocks\n");
+ return ret;
+ }
+
+ scp_reset_assert(scp);
+ /* Disable SCP watchdog */
+ writel(0, scp->reg_base + MT8183_WDT_CFG);
+ clk_disable_unprepare(scp->clk);
+
+ return 0;
+}
+
+static const struct rproc_ops scp_ops = {
+ .start = scp_start,
+ .stop = scp_stop,
+ .load = scp_load,
+ .da_to_va = scp_da_to_va,
+};
+
+/**
+ * scp_get_device() - get device struct of SCP
+ *
+ * @scp: mtk_scp structure
+ **/
+struct device *scp_get_device(struct mtk_scp *scp)
+{
+ return scp->dev;
+}
+EXPORT_SYMBOL_GPL(scp_get_device);
+
+/**
+ * scp_get_rproc() - get rproc struct of SCP
+ *
+ * @scp: mtk_scp structure
+ **/
+struct rproc *scp_get_rproc(struct mtk_scp *scp)
+{
+ return scp->rproc;
+}
+EXPORT_SYMBOL_GPL(scp_get_rproc);
+
+/**
+ * scp_get_vdec_hw_capa() - get video decoder hardware capability
+ *
+ * @scp: mtk_scp structure
+ *
+ * Return: video decoder hardware capability
+ **/
+unsigned int scp_get_vdec_hw_capa(struct mtk_scp *scp)
+{
+ return scp->run.dec_capability;
+}
+EXPORT_SYMBOL_GPL(scp_get_vdec_hw_capa);
+
+/**
+ * scp_get_venc_hw_capa() - get video encoder hardware capability
+ *
+ * @scp: mtk_scp structure
+ *
+ * Return: video encoder hardware capability
+ **/
+unsigned int scp_get_venc_hw_capa(struct mtk_scp *scp)
+{
+ return scp->run.enc_capability;
+}
+EXPORT_SYMBOL_GPL(scp_get_venc_hw_capa);
+
+/**
+ * scp_mapping_dm_addr() - Mapping SRAM/DRAM to kernel virtual address
+ *
+ * @scp: mtk_scp structure
+ * @mem_addr: SCP views memory address
+ *
+ * Mapping the SCP's SRAM address /
+ * DMEM (Data Extended Memory) memory address /
+ * Working buffer memory address to
+ * kernel virtual address.
+ *
+ * Return: Return ERR_PTR(-EINVAL) if mapping failed,
+ * otherwise the mapped kernel virtual address
+ **/
+void *scp_mapping_dm_addr(struct mtk_scp *scp, u32 mem_addr)
+{
+ void *ptr;
+
+ ptr = scp_da_to_va(scp->rproc, mem_addr, 0);
+ if (!ptr)
+ return ERR_PTR(-EINVAL);
+
+ return ptr;
+}
+EXPORT_SYMBOL_GPL(scp_mapping_dm_addr);
+
+static int scp_map_memory_region(struct mtk_scp *scp)
+{
+ int ret;
+
+ ret = of_reserved_mem_device_init(scp->dev);
+ if (ret) {
+ dev_err(scp->dev, "failed to assign memory-region: %d\n", ret);
+ return -ENOMEM;
+ }
+
+ /* Reserved SCP code size */
+ scp->dram_size = MAX_CODE_SIZE;
+ scp->cpu_addr = dma_alloc_coherent(scp->dev, scp->dram_size,
+ &scp->phys_addr, GFP_KERNEL);
+ if (!scp->cpu_addr)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void scp_unmap_memory_region(struct mtk_scp *scp)
+{
+ dma_free_coherent(scp->dev, scp->dram_size, scp->cpu_addr,
+ scp->phys_addr);
+ of_reserved_mem_device_release(scp->dev);
+}
+
+static int scp_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct mtk_scp *scp;
+ struct rproc *rproc;
+ struct resource *res;
+ char *fw_name = "scp.img";
+ int ret, i;
+
+ rproc = rproc_alloc(dev,
+ np->name,
+ &scp_ops,
+ fw_name,
+ sizeof(*scp));
+ if (!rproc) {
+ dev_err(dev, "unable to allocate remoteproc\n");
+ return -ENOMEM;
+ }
+
+ scp = (struct mtk_scp *)rproc->priv;
+ scp->rproc = rproc;
+ scp->dev = dev;
+ platform_set_drvdata(pdev, scp);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
+ scp->sram_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR((__force void *)scp->sram_base)) {
+ dev_err(dev, "Failed to parse and map sram memory\n");
+ ret = PTR_ERR((__force void *)scp->sram_base);
+ goto free_rproc;
+ }
+ scp->sram_size = resource_size(res);
+
+ mutex_init(&scp->send_lock);
+ for (i = 0; i < SCP_IPI_MAX; i++)
+ mutex_init(&scp->ipi_desc[i].lock);
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
+ scp->reg_base = devm_ioremap_resource(dev, res);
+ if (IS_ERR((__force void *)scp->reg_base)) {
+ dev_err(dev, "Failed to parse and map cfg memory\n");
+ ret = PTR_ERR((__force void *)scp->reg_base);
+ goto destroy_mutex;
+ }
+
+ ret = scp_map_memory_region(scp);
+ if (ret)
+ goto destroy_mutex;
+
+ scp->clk = devm_clk_get(dev, "main");
+ if (IS_ERR(scp->clk)) {
+ dev_err(dev, "Failed to get clock\n");
+ ret = PTR_ERR(scp->clk);
+ goto release_dev_mem;
+ }
+
+ ret = clk_prepare_enable(scp->clk);
+ if (ret) {
+ dev_err(dev, "failed to enable clocks\n");
+ goto release_dev_mem;
+ }
+
+ ret = scp_ipi_init(scp);
+ clk_disable_unprepare(scp->clk);
+ if (ret) {
+ dev_err(dev, "Failed to init ipi\n");
+ goto release_dev_mem;
+ }
+
+ /* register SCP initialization IPI */
+ ret = scp_ipi_register(scp, SCP_IPI_INIT, scp_init_ipi_handler, scp);
+ if (ret) {
+ dev_err(dev, "Failed to register IPI_SCP_INIT\n");
+ goto release_dev_mem;
+ }
+
+ init_waitqueue_head(&scp->run.wq);
+ init_waitqueue_head(&scp->ack_wq);
+
+ ret = devm_request_threaded_irq(dev, platform_get_irq(pdev, 0), NULL,
+ scp_irq_handler, IRQF_ONESHOT,
+ pdev->name, scp);
+
+ if (ret) {
+ dev_err(dev, "failed to request irq\n");
+ goto unregister_ipi;
+ }
+
+ ret = rproc_add(rproc);
+ if (ret)
+ goto unregister_ipi;
+
+ return ret;
+
+unregister_ipi:
+ scp_ipi_unregister(scp, SCP_IPI_INIT);
+release_dev_mem:
+ scp_unmap_memory_region(scp);
+destroy_mutex:
+ for (i = 0; i < SCP_IPI_MAX; i++)
+ mutex_destroy(&scp->ipi_desc[i].lock);
+ mutex_destroy(&scp->send_lock);
+free_rproc:
+ rproc_free(rproc);
+
+ return ret;
+}
+
+static int scp_remove(struct platform_device *pdev)
+{
+ struct mtk_scp *scp = platform_get_drvdata(pdev);
+ int i;
+
+ rproc_del(scp->rproc);
+ scp_ipi_unregister(scp, SCP_IPI_INIT);
+ scp_unmap_memory_region(scp);
+ for (i = 0; i < SCP_IPI_MAX; i++)
+ mutex_destroy(&scp->ipi_desc[i].lock);
+ mutex_destroy(&scp->send_lock);
+ rproc_free(scp->rproc);
+
+ return 0;
+}
+
+static const struct of_device_id mtk_scp_of_match[] = {
+ { .compatible = "mediatek,mt8183-scp"},
+ {},
+};
+MODULE_DEVICE_TABLE(of, mtk_scp_of_match);
+
+static struct platform_driver mtk_scp_driver = {
+ .probe = scp_probe,
+ .remove = scp_remove,
+ .driver = {
+ .name = "mtk-scp",
+ .of_match_table = of_match_ptr(mtk_scp_of_match),
+ },
+};
+
+module_platform_driver(mtk_scp_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MediaTek SCP control driver");
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (c) 2019 MediaTek Inc.
+
+#include <asm/barrier.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/remoteproc/mtk_scp.h>
+
+#include "mtk_common.h"
+
+/**
+ * scp_ipi_register() - register an ipi function
+ *
+ * @scp: mtk_scp structure
+ * @id: IPI ID
+ * @handler: IPI handler
+ * @priv: private data for IPI handler
+ *
+ * Register an ipi function to receive ipi interrupt from SCP.
+ *
+ * Returns 0 if ipi registers successfully, -error on error.
+ */
+int scp_ipi_register(struct mtk_scp *scp,
+ u32 id,
+ scp_ipi_handler_t handler,
+ void *priv)
+{
+ if (!scp) {
+ dev_err(scp->dev, "scp device is not ready\n");
+ return -EPROBE_DEFER;
+ }
+
+ if (WARN_ON(id >= SCP_IPI_MAX) || WARN_ON(handler == NULL))
+ return -EINVAL;
+
+ scp_ipi_lock(scp, id);
+ scp->ipi_desc[id].handler = handler;
+ scp->ipi_desc[id].priv = priv;
+ scp_ipi_unlock(scp, id);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(scp_ipi_register);
+
+/**
+ * scp_ipi_unregister() - unregister an ipi function
+ *
+ * @scp: mtk_scp structure
+ * @id: IPI ID
+ *
+ * Unregister an ipi function to receive ipi interrupt from SCP.
+ */
+void scp_ipi_unregister(struct mtk_scp *scp, u32 id)
+{
+ if (!scp)
+ return;
+
+ if (WARN_ON(id >= SCP_IPI_MAX))
+ return;
+
+ scp_ipi_lock(scp, id);
+ scp->ipi_desc[id].handler = NULL;
+ scp->ipi_desc[id].priv = NULL;
+ scp_ipi_unlock(scp, id);
+}
+EXPORT_SYMBOL_GPL(scp_ipi_unregister);
+
+/*
+ * scp_memcpy_aligned() - Copy src to dst, where dst is in SCP SRAM region.
+ *
+ * @dst: Pointer to the destination buffer, should be in SCP SRAM region.
+ * @src: Pointer to the source buffer.
+ * @len: Length of the source buffer to be copied.
+ *
+ * Since AP access of SCP SRAM don't support byte write, this always write a
+ * full word at a time, and may cause some extra bytes to be written at the
+ * beginning & ending of dst.
+ */
+void scp_memcpy_aligned(void __iomem *dst, const void *src, unsigned int len)
+{
+ void __iomem *ptr;
+ u32 val;
+ unsigned int i = 0, remain;
+
+ if (!IS_ALIGNED((unsigned long)dst, 4)) {
+ ptr = (void __iomem *)ALIGN_DOWN((unsigned long)dst, 4);
+ i = 4 - (dst - ptr);
+ val = readl_relaxed(ptr);
+ memcpy((u8 *)&val + (4 - i), src, i);
+ writel_relaxed(val, ptr);
+ }
+
+ __iowrite32_copy(dst + i, src + i, (len - i) / 4);
+ remain = (len - i) % 4;
+
+ if (remain > 0) {
+ val = readl_relaxed(dst + len - remain);
+ memcpy(&val, src + len - remain, remain);
+ writel_relaxed(val, dst + len - remain);
+ }
+}
+EXPORT_SYMBOL_GPL(scp_memcpy_aligned);
+
+/**
+ * scp_ipi_lock() - Lock before operations of an IPI ID
+ *
+ * @scp: mtk_scp structure
+ * @id: IPI ID
+ *
+ * Note: This should not be used by drivers other than mtk_scp.
+ */
+void scp_ipi_lock(struct mtk_scp *scp, u32 id)
+{
+ if (WARN_ON(id >= SCP_IPI_MAX))
+ return;
+ mutex_lock(&scp->ipi_desc[id].lock);
+}
+EXPORT_SYMBOL_GPL(scp_ipi_lock);
+
+/**
+ * scp_ipi_lock() - Unlock after operations of an IPI ID
+ *
+ * @scp: mtk_scp structure
+ * @id: IPI ID
+ *
+ * Note: This should not be used by drivers other than mtk_scp.
+ */
+void scp_ipi_unlock(struct mtk_scp *scp, u32 id)
+{
+ if (WARN_ON(id >= SCP_IPI_MAX))
+ return;
+ mutex_unlock(&scp->ipi_desc[id].lock);
+}
+EXPORT_SYMBOL_GPL(scp_ipi_unlock);
+
+/**
+ * scp_ipi_send() - send data from AP to scp.
+ *
+ * @scp: mtk_scp structure
+ * @id: IPI ID
+ * @buf: the data buffer
+ * @len: the data buffer length
+ * @wait: number of msecs to wait for ack. 0 to skip waiting.
+ *
+ * This function is thread-safe. When this function returns,
+ * SCP has received the data and starts the processing.
+ * When the processing completes, IPI handler registered
+ * by scp_ipi_register will be called in interrupt context.
+ *
+ * Returns 0 if sending data successfully, -error on error.
+ **/
+int scp_ipi_send(struct mtk_scp *scp, u32 id, void *buf, unsigned int len,
+ unsigned int wait)
+{
+ struct mtk_share_obj __iomem *send_obj = scp->send_buf;
+ unsigned long timeout;
+ int ret;
+
+ if (WARN_ON(id <= SCP_IPI_INIT) || WARN_ON(id >= SCP_IPI_MAX) ||
+ WARN_ON(len > sizeof(send_obj->share_buf)) || WARN_ON(!buf))
+ return -EINVAL;
+
+ mutex_lock(&scp->send_lock);
+
+ ret = clk_prepare_enable(scp->clk);
+ if (ret) {
+ dev_err(scp->dev, "failed to enable clock\n");
+ goto unlock_mutex;
+ }
+
+ /* Wait until SCP receives the last command */
+ timeout = jiffies + msecs_to_jiffies(2000);
+ do {
+ if (time_after(jiffies, timeout)) {
+ dev_err(scp->dev, "%s: IPI timeout!\n", __func__);
+ ret = -ETIMEDOUT;
+ goto clock_disable;
+ }
+ } while (readl(scp->reg_base + MT8183_HOST_TO_SCP));
+
+ scp_memcpy_aligned(send_obj->share_buf, buf, len);
+
+ writel(len, &send_obj->len);
+ writel(id, &send_obj->id);
+
+ scp->ipi_id_ack[id] = false;
+ /* send the command to SCP */
+ writel(MT8183_HOST_IPC_INT_BIT, scp->reg_base + MT8183_HOST_TO_SCP);
+
+ if (wait) {
+ /* wait for SCP's ACK */
+ timeout = msecs_to_jiffies(wait);
+ ret = wait_event_timeout(scp->ack_wq,
+ scp->ipi_id_ack[id],
+ timeout);
+ scp->ipi_id_ack[id] = false;
+ if (WARN(!ret, "scp ipi %d ack time out !", id))
+ ret = -EIO;
+ else
+ ret = 0;
+ }
+
+clock_disable:
+ clk_disable_unprepare(scp->clk);
+unlock_mutex:
+ mutex_unlock(&scp->send_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(scp_ipi_send);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MediaTek scp IPI interface");
projects / platform / kernel / linux-rpi.git / commitdiff