--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2015-2021, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2022, Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#define STATUS_READY_TIMEOUT 5000 /* microseconds */
+
+#define DCC_SRAM_NODE "dcc_sram"
+
+/* DCC registers */
+#define DCC_HW_INFO 0x04
+#define DCC_LL_NUM_INFO 0x10
+#define DCC_STATUS(vers) ((vers) == 1 ? 0x0c : 0x1c)
+#define DCC_LL_LOCK 0x00
+#define DCC_LL_CFG 0x04
+#define DCC_LL_BASE 0x08
+#define DCC_FD_BASE 0x0c
+#define DCC_LL_TIMEOUT 0x10
+#define DCC_LL_INT_ENABLE 0x18
+#define DCC_LL_INT_STATUS 0x1c
+#define DCC_LL_SW_TRIGGER 0x2c
+#define DCC_LL_BUS_ACCESS_STATUS 0x30
+
+/* Default value used if a bit 6 in the HW_INFO register is set. */
+#define DCC_FIX_LOOP_OFFSET 16
+
+/* Mask to find version info from HW_Info register */
+#define DCC_VER_INFO_MASK BIT(9)
+
+#define MAX_DCC_OFFSET GENMASK(9, 2)
+#define MAX_DCC_LEN GENMASK(6, 0)
+#define MAX_LOOP_CNT GENMASK(7, 0)
+#define MAX_LOOP_ADDR 10
+
+#define DCC_ADDR_DESCRIPTOR 0x00
+#define DCC_ADDR_LIMIT 27
+#define DCC_WORD_SIZE sizeof(u32)
+#define DCC_ADDR_RANGE_MASK GENMASK(31, 4)
+#define DCC_LOOP_DESCRIPTOR BIT(30)
+#define DCC_RD_MOD_WR_DESCRIPTOR BIT(31)
+#define DCC_LINK_DESCRIPTOR GENMASK(31, 30)
+#define DCC_STATUS_MASK GENMASK(1, 0)
+#define DCC_LOCK_MASK BIT(0)
+#define DCC_LOOP_OFFSET_MASK BIT(6)
+#define DCC_TRIGGER_MASK BIT(9)
+
+#define DCC_WRITE_MASK BIT(15)
+#define DCC_WRITE_OFF_MASK GENMASK(7, 0)
+#define DCC_WRITE_LEN_MASK GENMASK(14, 8)
+
+#define DCC_READ_IND 0x00
+#define DCC_WRITE_IND (BIT(28))
+
+#define DCC_AHB_IND 0x00
+#define DCC_APB_IND BIT(29)
+
+#define DCC_MAX_LINK_LIST 8
+
+#define DCC_VER_MASK2 GENMASK(5, 0)
+
+#define DCC_SRAM_WORD_LENGTH 4
+
+#define DCC_RD_MOD_WR_ADDR 0xc105e
+
+enum dcc_descriptor_type {
+ DCC_READ_TYPE,
+ DCC_LOOP_TYPE,
+ DCC_READ_WRITE_TYPE,
+ DCC_WRITE_TYPE
+};
+
+struct dcc_config_entry {
+ u32 base;
+ u32 offset;
+ u32 len;
+ u32 loop_cnt;
+ u32 write_val;
+ u32 mask;
+ bool apb_bus;
+ enum dcc_descriptor_type desc_type;
+ struct list_head list;
+};
+
+/**
+ * struct dcc_drvdata - configuration information related to a dcc device
+ * @base: Base Address of the dcc device
+ * @dev: The device attached to the driver data
+ * @mutex: Lock to protect access and manipulation of dcc_drvdata
+ * @ram_base: Base address for the SRAM dedicated for the dcc device
+ * @ram_size: Total size of the SRAM dedicated for the dcc device
+ * @ram_offset: Offset to the SRAM dedicated for dcc device
+ * @mem_map_ver: Memory map version of DCC hardware
+ * @ram_cfg: Used for address limit calculation for dcc
+ * @ram_start: Starting address of DCC SRAM
+ * @sram_dev: Miscellaneous device equivalent of dcc SRAM
+ * @cfg_head: Points to the head of the linked list of addresses
+ * @dbg_dir: The dcc debugfs directory under which all the debugfs files are placed
+ * @nr_link_list: Total number of linkedlists supported by the DCC configuration
+ * @loop_shift: Loop offset bits range for the addresses
+ * @enable_bitmap: Bitmap to capture the enabled status of each linked list of addresses
+ */
+struct dcc_drvdata {
+ void __iomem *base;
+ void __iomem *ram_base;
+ struct device *dev;
+ struct mutex mutex;
+ size_t ram_size;
+ size_t ram_offset;
+ int mem_map_ver;
+ unsigned int ram_cfg;
+ unsigned int ram_start;
+ struct miscdevice sram_dev;
+ struct list_head *cfg_head;
+ struct dentry *dbg_dir;
+ size_t nr_link_list;
+ u8 loop_shift;
+ unsigned long *enable_bitmap;
+};
+
+struct dcc_cfg_attr {
+ u32 addr;
+ u32 prev_addr;
+ u32 prev_off;
+ u32 link;
+ u32 sram_offset;
+};
+
+struct dcc_cfg_loop_attr {
+ u32 loop_cnt;
+ u32 loop_len;
+ u32 loop_off;
+ bool loop_start;
+};
+
+static inline u32 dcc_list_offset(int version)
+{
+ return version == 1 ? 0x1c : version == 2 ? 0x2c : 0x34;
+}
+
+static inline void dcc_list_writel(struct dcc_drvdata *drvdata,
+ u32 ll, u32 val, u32 off)
+{
+ u32 offset = dcc_list_offset(drvdata->mem_map_ver) + off;
+
+ writel(val, drvdata->base + ll * 0x80 + offset);
+}
+
+static inline u32 dcc_list_readl(struct dcc_drvdata *drvdata, u32 ll, u32 off)
+{
+ u32 offset = dcc_list_offset(drvdata->mem_map_ver) + off;
+
+ return readl(drvdata->base + ll * 0x80 + offset);
+}
+
+static void dcc_sram_write_auto(struct dcc_drvdata *drvdata,
+ u32 val, u32 *off)
+{
+ /* If the overflow condition is met increment the offset
+ * and return to indicate that overflow has occurred
+ */
+ if (unlikely(*off > drvdata->ram_size - 4)) {
+ *off += 4;
+ return;
+ }
+
+ writel(val, drvdata->ram_base + *off);
+
+ *off += 4;
+}
+
+static int dcc_sw_trigger(struct dcc_drvdata *drvdata)
+{
+ void __iomem *addr;
+ int ret = 0;
+ int i;
+ u32 status;
+ u32 ll_cfg;
+ u32 tmp_ll_cfg;
+ u32 val;
+
+ mutex_lock(&drvdata->mutex);
+
+ for (i = 0; i < drvdata->nr_link_list; i++) {
+ if (!test_bit(i, drvdata->enable_bitmap))
+ continue;
+ ll_cfg = dcc_list_readl(drvdata, i, DCC_LL_CFG);
+ tmp_ll_cfg = ll_cfg & ~DCC_TRIGGER_MASK;
+ dcc_list_writel(drvdata, tmp_ll_cfg, i, DCC_LL_CFG);
+ dcc_list_writel(drvdata, 1, i, DCC_LL_SW_TRIGGER);
+ dcc_list_writel(drvdata, ll_cfg, i, DCC_LL_CFG);
+ }
+
+ addr = drvdata->base + DCC_STATUS(drvdata->mem_map_ver);
+ if (readl_poll_timeout(addr, val, !FIELD_GET(DCC_STATUS_MASK, val),
+ 1, STATUS_READY_TIMEOUT)) {
+ dev_err(drvdata->dev, "DCC is busy after receiving sw trigger\n");
+ ret = -EBUSY;
+ goto out_unlock;
+ }
+
+ for (i = 0; i < drvdata->nr_link_list; i++) {
+ if (!test_bit(i, drvdata->enable_bitmap))
+ continue;
+
+ status = dcc_list_readl(drvdata, i, DCC_LL_BUS_ACCESS_STATUS);
+ if (!status)
+ continue;
+
+ dev_err(drvdata->dev, "Read access error for list %d err: 0x%x\n",
+ i, status);
+ ll_cfg = dcc_list_readl(drvdata, i, DCC_LL_CFG);
+ tmp_ll_cfg = ll_cfg & ~DCC_TRIGGER_MASK;
+ dcc_list_writel(drvdata, tmp_ll_cfg, i, DCC_LL_CFG);
+ dcc_list_writel(drvdata, DCC_STATUS_MASK, i, DCC_LL_BUS_ACCESS_STATUS);
+ dcc_list_writel(drvdata, ll_cfg, i, DCC_LL_CFG);
+ ret = -ENODATA;
+ break;
+ }
+
+out_unlock:
+ mutex_unlock(&drvdata->mutex);
+ return ret;
+}
+
+static void dcc_ll_cfg_reset_link(struct dcc_cfg_attr *cfg)
+{
+ cfg->addr = 0x00;
+ cfg->link = 0;
+ cfg->prev_off = 0;
+ cfg->prev_addr = cfg->addr;
+}
+
+static void dcc_emit_read_write(struct dcc_drvdata *drvdata,
+ struct dcc_config_entry *entry,
+ struct dcc_cfg_attr *cfg)
+{
+ if (cfg->link) {
+ /*
+ * write new offset = 1 to continue
+ * processing the list
+ */
+
+ dcc_sram_write_auto(drvdata, cfg->link, &cfg->sram_offset);
+
+ /* Reset link and prev_off */
+ dcc_ll_cfg_reset_link(cfg);
+ }
+
+ cfg->addr = DCC_RD_MOD_WR_DESCRIPTOR;
+ dcc_sram_write_auto(drvdata, cfg->addr, &cfg->sram_offset);
+
+ dcc_sram_write_auto(drvdata, entry->mask, &cfg->sram_offset);
+
+ dcc_sram_write_auto(drvdata, entry->write_val, &cfg->sram_offset);
+
+ cfg->addr = 0;
+}
+
+static void dcc_emit_loop(struct dcc_drvdata *drvdata, struct dcc_config_entry *entry,
+ struct dcc_cfg_attr *cfg,
+ struct dcc_cfg_loop_attr *cfg_loop,
+ u32 *total_len)
+{
+ int loop;
+
+ /* Check if we need to write link of prev entry */
+ if (cfg->link)
+ dcc_sram_write_auto(drvdata, cfg->link, &cfg->sram_offset);
+
+ if (cfg_loop->loop_start) {
+ loop = (cfg->sram_offset - cfg_loop->loop_off) / 4;
+ loop |= (cfg_loop->loop_cnt << drvdata->loop_shift) &
+ GENMASK(DCC_ADDR_LIMIT, drvdata->loop_shift);
+ loop |= DCC_LOOP_DESCRIPTOR;
+ *total_len += (*total_len - cfg_loop->loop_len) * cfg_loop->loop_cnt;
+
+ dcc_sram_write_auto(drvdata, loop, &cfg->sram_offset);
+
+ cfg_loop->loop_start = false;
+ cfg_loop->loop_len = 0;
+ cfg_loop->loop_off = 0;
+ } else {
+ cfg_loop->loop_start = true;
+ cfg_loop->loop_cnt = entry->loop_cnt - 1;
+ cfg_loop->loop_len = *total_len;
+ cfg_loop->loop_off = cfg->sram_offset;
+ }
+
+ /* Reset link and prev_off */
+ dcc_ll_cfg_reset_link(cfg);
+}
+
+static void dcc_emit_write(struct dcc_drvdata *drvdata,
+ struct dcc_config_entry *entry,
+ struct dcc_cfg_attr *cfg)
+{
+ u32 off;
+
+ if (cfg->link) {
+ /*
+ * write new offset = 1 to continue
+ * processing the list
+ */
+ dcc_sram_write_auto(drvdata, cfg->link, &cfg->sram_offset);
+
+ /* Reset link and prev_off */
+ cfg->addr = 0x00;
+ cfg->prev_off = 0;
+ cfg->prev_addr = cfg->addr;
+ }
+
+ off = entry->offset / 4;
+ /* write new offset-length pair to correct position */
+ cfg->link |= ((off & DCC_WRITE_OFF_MASK) | DCC_WRITE_MASK |
+ FIELD_PREP(DCC_WRITE_LEN_MASK, entry->len));
+ cfg->link |= DCC_LINK_DESCRIPTOR;
+
+ /* Address type */
+ cfg->addr = (entry->base >> 4) & GENMASK(DCC_ADDR_LIMIT, 0);
+ if (entry->apb_bus)
+ cfg->addr |= DCC_ADDR_DESCRIPTOR | DCC_WRITE_IND | DCC_APB_IND;
+ else
+ cfg->addr |= DCC_ADDR_DESCRIPTOR | DCC_WRITE_IND | DCC_AHB_IND;
+ dcc_sram_write_auto(drvdata, cfg->addr, &cfg->sram_offset);
+
+ dcc_sram_write_auto(drvdata, cfg->link, &cfg->sram_offset);
+
+ dcc_sram_write_auto(drvdata, entry->write_val, &cfg->sram_offset);
+
+ cfg->addr = 0x00;
+ cfg->link = 0;
+}
+
+static int dcc_emit_read(struct dcc_drvdata *drvdata,
+ struct dcc_config_entry *entry,
+ struct dcc_cfg_attr *cfg,
+ u32 *pos, u32 *total_len)
+{
+ u32 off;
+ u32 temp_off;
+
+ cfg->addr = (entry->base >> 4) & GENMASK(27, 0);
+
+ if (entry->apb_bus)
+ cfg->addr |= DCC_ADDR_DESCRIPTOR | DCC_READ_IND | DCC_APB_IND;
+ else
+ cfg->addr |= DCC_ADDR_DESCRIPTOR | DCC_READ_IND | DCC_AHB_IND;
+
+ off = entry->offset / 4;
+
+ *total_len += entry->len * 4;
+
+ if (!cfg->prev_addr || cfg->prev_addr != cfg->addr || cfg->prev_off > off) {
+ /* Check if we need to write prev link entry */
+ if (cfg->link)
+ dcc_sram_write_auto(drvdata, cfg->link, &cfg->sram_offset);
+ dev_dbg(drvdata->dev, "DCC: sram address 0x%x\n", cfg->sram_offset);
+
+ /* Write address */
+ dcc_sram_write_auto(drvdata, cfg->addr, &cfg->sram_offset);
+
+ /* Reset link and prev_off */
+ cfg->link = 0;
+ cfg->prev_off = 0;
+ }
+
+ if ((off - cfg->prev_off) > 0xff || entry->len > MAX_DCC_LEN) {
+ dev_err(drvdata->dev, "DCC: Programming error Base: 0x%x, offset 0x%x\n",
+ entry->base, entry->offset);
+ return -EINVAL;
+ }
+
+ if (cfg->link) {
+ /*
+ * link already has one offset-length so new
+ * offset-length needs to be placed at
+ * bits [29:15]
+ */
+ *pos = 15;
+
+ /* Clear bits [31:16] */
+ cfg->link &= GENMASK(14, 0);
+ } else {
+ /*
+ * link is empty, so new offset-length needs
+ * to be placed at bits [15:0]
+ */
+ *pos = 0;
+ cfg->link = 1 << 15;
+ }
+
+ /* write new offset-length pair to correct position */
+ temp_off = (off - cfg->prev_off) & GENMASK(7, 0);
+ cfg->link |= temp_off | ((entry->len << 8) & GENMASK(14, 8)) << *pos;
+
+ cfg->link |= DCC_LINK_DESCRIPTOR;
+
+ if (*pos) {
+ dcc_sram_write_auto(drvdata, cfg->link, &cfg->sram_offset);
+ cfg->link = 0;
+ }
+
+ cfg->prev_off = off + entry->len - 1;
+ cfg->prev_addr = cfg->addr;
+ return 0;
+}
+
+static int dcc_emit_config(struct dcc_drvdata *drvdata, unsigned int curr_list)
+{
+ int ret;
+ u32 total_len, pos;
+ struct dcc_config_entry *entry;
+ struct dcc_cfg_attr cfg;
+ struct dcc_cfg_loop_attr cfg_loop;
+
+ memset(&cfg, 0, sizeof(cfg));
+ memset(&cfg_loop, 0, sizeof(cfg_loop));
+ cfg.sram_offset = drvdata->ram_cfg * 4;
+ total_len = 0;
+
+ list_for_each_entry(entry, &drvdata->cfg_head[curr_list], list) {
+ switch (entry->desc_type) {
+ case DCC_READ_WRITE_TYPE:
+ dcc_emit_read_write(drvdata, entry, &cfg);
+ break;
+
+ case DCC_LOOP_TYPE:
+ dcc_emit_loop(drvdata, entry, &cfg, &cfg_loop, &total_len);
+ break;
+
+ case DCC_WRITE_TYPE:
+ dcc_emit_write(drvdata, entry, &cfg);
+ break;
+
+ case DCC_READ_TYPE:
+ ret = dcc_emit_read(drvdata, entry, &cfg, &pos, &total_len);
+ if (ret)
+ goto err;
+ break;
+ }
+ }
+
+ if (cfg.link)
+ dcc_sram_write_auto(drvdata, cfg.link, &cfg.sram_offset);
+
+ if (cfg_loop.loop_start) {
+ dev_err(drvdata->dev, "DCC: Programming error: Loop unterminated\n");
+ ret = -EINVAL;
+ goto err;
+ }
+
+ /* Handling special case of list ending with a rd_mod_wr */
+ if (cfg.addr == DCC_RD_MOD_WR_DESCRIPTOR) {
+ cfg.addr = (DCC_RD_MOD_WR_ADDR) & GENMASK(27, 0);
+ cfg.addr |= DCC_ADDR_DESCRIPTOR;
+ dcc_sram_write_auto(drvdata, cfg.addr, &cfg.sram_offset);
+ }
+
+ /* Setting zero to indicate end of the list */
+ cfg.link = DCC_LINK_DESCRIPTOR;
+ dcc_sram_write_auto(drvdata, cfg.link, &cfg.sram_offset);
+
+ /* Check if sram offset exceeds the ram size */
+ if (cfg.sram_offset > drvdata->ram_size)
+ goto overstep;
+
+ /* Update ram_cfg and check if the data will overstep */
+ drvdata->ram_cfg = (cfg.sram_offset + total_len) / 4;
+
+ if (cfg.sram_offset + total_len > drvdata->ram_size) {
+ cfg.sram_offset += total_len;
+ goto overstep;
+ }
+
+ drvdata->ram_start = cfg.sram_offset / 4;
+ return 0;
+overstep:
+ ret = -EINVAL;
+ memset_io(drvdata->ram_base, 0, drvdata->ram_size);
+
+err:
+ return ret;
+}
+
+static bool dcc_valid_list(struct dcc_drvdata *drvdata, unsigned int curr_list)
+{
+ u32 lock_reg;
+
+ if (list_empty(&drvdata->cfg_head[curr_list]))
+ return false;
+
+ if (test_bit(curr_list, drvdata->enable_bitmap)) {
+ dev_err(drvdata->dev, "List %d is already enabled\n", curr_list);
+ return false;
+ }
+
+ lock_reg = dcc_list_readl(drvdata, curr_list, DCC_LL_LOCK);
+ if (lock_reg & DCC_LOCK_MASK) {
+ dev_err(drvdata->dev, "List %d is already locked\n", curr_list);
+ return false;
+ }
+
+ return true;
+}
+
+static bool is_dcc_enabled(struct dcc_drvdata *drvdata)
+{
+ int list;
+
+ for (list = 0; list < drvdata->nr_link_list; list++)
+ if (test_bit(list, drvdata->enable_bitmap))
+ return true;
+
+ return false;
+}
+
+static int dcc_enable(struct dcc_drvdata *drvdata, unsigned int curr_list)
+{
+ int ret;
+ u32 ram_cfg_base;
+
+ mutex_lock(&drvdata->mutex);
+
+ if (!dcc_valid_list(drvdata, curr_list)) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ /* Fill dcc sram with the poison value.
+ * This helps in understanding bus
+ * hang from registers returning a zero
+ */
+ if (!is_dcc_enabled(drvdata))
+ memset_io(drvdata->ram_base, 0xde, drvdata->ram_size);
+
+ /* 1. Take ownership of the list */
+ dcc_list_writel(drvdata, DCC_LOCK_MASK, curr_list, DCC_LL_LOCK);
+
+ /* 2. Program linked-list in the SRAM */
+ ram_cfg_base = drvdata->ram_cfg;
+ ret = dcc_emit_config(drvdata, curr_list);
+ if (ret) {
+ dcc_list_writel(drvdata, 0, curr_list, DCC_LL_LOCK);
+ goto out_unlock;
+ }
+
+ /* 3. Program DCC_RAM_CFG reg */
+ dcc_list_writel(drvdata, ram_cfg_base +
+ drvdata->ram_offset / 4, curr_list, DCC_LL_BASE);
+ dcc_list_writel(drvdata, drvdata->ram_start +
+ drvdata->ram_offset / 4, curr_list, DCC_FD_BASE);
+ dcc_list_writel(drvdata, 0xFFF, curr_list, DCC_LL_TIMEOUT);
+
+ /* 4. Clears interrupt status register */
+ dcc_list_writel(drvdata, 0, curr_list, DCC_LL_INT_ENABLE);
+ dcc_list_writel(drvdata, (BIT(0) | BIT(1) | BIT(2)),
+ curr_list, DCC_LL_INT_STATUS);
+
+ set_bit(curr_list, drvdata->enable_bitmap);
+
+ /* 5. Configure trigger */
+ dcc_list_writel(drvdata, DCC_TRIGGER_MASK,
+ curr_list, DCC_LL_CFG);
+
+out_unlock:
+ mutex_unlock(&drvdata->mutex);
+ return ret;
+}
+
+static void dcc_disable(struct dcc_drvdata *drvdata, int curr_list)
+{
+ mutex_lock(&drvdata->mutex);
+
+ if (!test_bit(curr_list, drvdata->enable_bitmap))
+ goto out_unlock;
+ dcc_list_writel(drvdata, 0, curr_list, DCC_LL_CFG);
+ dcc_list_writel(drvdata, 0, curr_list, DCC_LL_BASE);
+ dcc_list_writel(drvdata, 0, curr_list, DCC_FD_BASE);
+ dcc_list_writel(drvdata, 0, curr_list, DCC_LL_LOCK);
+ clear_bit(curr_list, drvdata->enable_bitmap);
+out_unlock:
+ mutex_unlock(&drvdata->mutex);
+}
+
+static u32 dcc_filp_curr_list(const struct file *filp)
+{
+ struct dentry *dentry = file_dentry(filp);
+ int curr_list, ret;
+
+ ret = kstrtoint(dentry->d_parent->d_name.name, 0, &curr_list);
+ if (ret)
+ return ret;
+
+ return curr_list;
+}
+
+static ssize_t enable_read(struct file *filp, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ char *buf;
+ struct dcc_drvdata *drvdata = filp->private_data;
+
+ mutex_lock(&drvdata->mutex);
+
+ if (is_dcc_enabled(drvdata))
+ buf = "Y\n";
+ else
+ buf = "N\n";
+
+ mutex_unlock(&drvdata->mutex);
+
+ return simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf));
+}
+
+static ssize_t enable_write(struct file *filp, const char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ int ret = 0, curr_list;
+ bool val;
+ struct dcc_drvdata *drvdata = filp->private_data;
+
+ curr_list = dcc_filp_curr_list(filp);
+ if (curr_list < 0)
+ return curr_list;
+
+ ret = kstrtobool_from_user(userbuf, count, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val) {
+ ret = dcc_enable(drvdata, curr_list);
+ if (ret)
+ return ret;
+ } else {
+ dcc_disable(drvdata, curr_list);
+ }
+
+ return count;
+}
+
+static const struct file_operations enable_fops = {
+ .read = enable_read,
+ .write = enable_write,
+ .open = simple_open,
+ .llseek = generic_file_llseek,
+};
+
+static ssize_t trigger_write(struct file *filp,
+ const char __user *user_buf, size_t count,
+ loff_t *ppos)
+{
+ int ret;
+ unsigned int val;
+ struct dcc_drvdata *drvdata = filp->private_data;
+
+ ret = kstrtouint_from_user(user_buf, count, 0, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val != 1)
+ return -EINVAL;
+
+ ret = dcc_sw_trigger(drvdata);
+ if (ret < 0)
+ return ret;
+
+ return count;
+}
+
+static const struct file_operations trigger_fops = {
+ .write = trigger_write,
+ .open = simple_open,
+ .llseek = generic_file_llseek,
+};
+
+static int dcc_config_add(struct dcc_drvdata *drvdata, unsigned int addr,
+ unsigned int len, bool apb_bus, int curr_list)
+{
+ int ret = 0;
+ struct dcc_config_entry *entry, *pentry;
+ unsigned int base, offset;
+
+ mutex_lock(&drvdata->mutex);
+
+ if (!len || len > drvdata->ram_size / DCC_WORD_SIZE) {
+ dev_err(drvdata->dev, "DCC: Invalid length\n");
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ base = addr & DCC_ADDR_RANGE_MASK;
+
+ if (!list_empty(&drvdata->cfg_head[curr_list])) {
+ pentry = list_last_entry(&drvdata->cfg_head[curr_list],
+ struct dcc_config_entry, list);
+
+ if (pentry->desc_type == DCC_READ_TYPE &&
+ addr >= (pentry->base + pentry->offset) &&
+ addr <= (pentry->base + pentry->offset + MAX_DCC_OFFSET)) {
+ /* Re-use base address from last entry */
+ base = pentry->base;
+
+ if ((pentry->len * 4 + pentry->base + pentry->offset)
+ == addr) {
+ len += pentry->len;
+
+ if (len > MAX_DCC_LEN)
+ pentry->len = MAX_DCC_LEN;
+ else
+ pentry->len = len;
+
+ addr = pentry->base + pentry->offset +
+ pentry->len * 4;
+ len -= pentry->len;
+ }
+ }
+ }
+
+ offset = addr - base;
+
+ while (len) {
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
+
+ entry->base = base;
+ entry->offset = offset;
+ entry->len = min_t(u32, len, MAX_DCC_LEN);
+ entry->desc_type = DCC_READ_TYPE;
+ entry->apb_bus = apb_bus;
+ INIT_LIST_HEAD(&entry->list);
+ list_add_tail(&entry->list, &drvdata->cfg_head[curr_list]);
+
+ len -= entry->len;
+ offset += MAX_DCC_LEN * 4;
+ }
+
+out_unlock:
+ mutex_unlock(&drvdata->mutex);
+ return ret;
+}
+
+static ssize_t dcc_config_add_read(struct dcc_drvdata *drvdata, char *buf, int curr_list)
+{
+ bool bus;
+ int len, nval;
+ unsigned int base;
+ char apb_bus[4];
+
+ nval = sscanf(buf, "%x %i %3s", &base, &len, apb_bus);
+ if (nval <= 0 || nval > 3)
+ return -EINVAL;
+
+ if (nval == 1) {
+ len = 1;
+ bus = false;
+ } else if (nval == 2) {
+ bus = false;
+ } else if (!strcmp("apb", apb_bus)) {
+ bus = true;
+ } else if (!strcmp("ahb", apb_bus)) {
+ bus = false;
+ } else {
+ return -EINVAL;
+ }
+
+ return dcc_config_add(drvdata, base, len, bus, curr_list);
+}
+
+static void dcc_config_reset(struct dcc_drvdata *drvdata)
+{
+ struct dcc_config_entry *entry, *temp;
+ int curr_list;
+
+ mutex_lock(&drvdata->mutex);
+
+ for (curr_list = 0; curr_list < drvdata->nr_link_list; curr_list++) {
+ list_for_each_entry_safe(entry, temp,
+ &drvdata->cfg_head[curr_list], list) {
+ list_del(&entry->list);
+ kfree(entry);
+ }
+ }
+ drvdata->ram_start = 0;
+ drvdata->ram_cfg = 0;
+ mutex_unlock(&drvdata->mutex);
+}
+
+static ssize_t config_reset_write(struct file *filp,
+ const char __user *user_buf, size_t count,
+ loff_t *ppos)
+{
+ unsigned int val, ret;
+ struct dcc_drvdata *drvdata = filp->private_data;
+
+ ret = kstrtouint_from_user(user_buf, count, 0, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val)
+ dcc_config_reset(drvdata);
+
+ return count;
+}
+
+static const struct file_operations config_reset_fops = {
+ .write = config_reset_write,
+ .open = simple_open,
+ .llseek = generic_file_llseek,
+};
+
+static ssize_t ready_read(struct file *filp, char __user *userbuf,
+ size_t count, loff_t *ppos)
+{
+ int ret = 0;
+ char *buf;
+ struct dcc_drvdata *drvdata = filp->private_data;
+
+ mutex_lock(&drvdata->mutex);
+
+ if (!is_dcc_enabled(drvdata)) {
+ ret = -EINVAL;
+ goto out_unlock;
+ }
+
+ if (!FIELD_GET(BIT(1), readl(drvdata->base + DCC_STATUS(drvdata->mem_map_ver))))
+ buf = "Y\n";
+ else
+ buf = "N\n";
+out_unlock:
+ mutex_unlock(&drvdata->mutex);
+
+ if (ret < 0)
+ return -EINVAL;
+ else
+ return simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf) + 1);
+}
+
+static const struct file_operations ready_fops = {
+ .read = ready_read,
+ .open = simple_open,
+ .llseek = generic_file_llseek,
+};
+
+static int dcc_add_loop(struct dcc_drvdata *drvdata, unsigned long loop_cnt, int curr_list)
+{
+ struct dcc_config_entry *entry;
+
+ entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->loop_cnt = min_t(u32, loop_cnt, MAX_LOOP_CNT);
+ entry->desc_type = DCC_LOOP_TYPE;
+ INIT_LIST_HEAD(&entry->list);
+ list_add_tail(&entry->list, &drvdata->cfg_head[curr_list]);
+
+ return 0;
+}
+
+static ssize_t dcc_config_add_loop(struct dcc_drvdata *drvdata, char *buf, int curr_list)
+{
+ int ret, i = 0;
+ char *token, *input;
+ char delim[2] = " ";
+ unsigned int val[MAX_LOOP_ADDR];
+
+ input = buf;
+
+ while ((token = strsep(&input, delim)) && i < MAX_LOOP_ADDR) {
+ ret = kstrtoint(token, 0, &val[i++]);
+ if (ret)
+ return ret;
+ }
+
+ if (token) {
+ dev_err(drvdata->dev, "Max limit %u of loop address exceeded",
+ MAX_LOOP_ADDR);
+ return -EINVAL;
+ }
+
+ if (val[1] < 1 || val[1] > 8)
+ return -EINVAL;
+
+ ret = dcc_add_loop(drvdata, val[0], curr_list);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < val[1]; i++)
+ dcc_config_add(drvdata, val[i + 2], 1, false, curr_list);
+
+ return dcc_add_loop(drvdata, 1, curr_list);
+}
+
+static int dcc_rd_mod_wr_add(struct dcc_drvdata *drvdata, unsigned int mask,
+ unsigned int val, int curr_list)
+{
+ int ret = 0;
+ struct dcc_config_entry *entry;
+
+ mutex_lock(&drvdata->mutex);
+
+ if (list_empty(&drvdata->cfg_head[curr_list])) {
+ dev_err(drvdata->dev, "DCC: No read address programmed\n");
+ ret = -EPERM;
+ goto out_unlock;
+ }
+
+ entry = devm_kzalloc(drvdata->dev, sizeof(*entry), GFP_KERNEL);
+ if (!entry) {
+ ret = -ENOMEM;
+ goto out_unlock;
+ }
+
+ entry->desc_type = DCC_READ_WRITE_TYPE;
+ entry->mask = mask;
+ entry->write_val = val;
+ list_add_tail(&entry->list, &drvdata->cfg_head[curr_list]);
+out_unlock:
+ mutex_unlock(&drvdata->mutex);
+ return ret;
+}
+
+static ssize_t dcc_config_add_read_write(struct dcc_drvdata *drvdata, char *buf, int curr_list)
+{
+ int ret;
+ int nval;
+ unsigned int addr, mask, val;
+
+ nval = sscanf(buf, "%x %x %x", &addr, &mask, &val);
+
+ if (nval <= 1 || nval > 3)
+ return -EINVAL;
+
+ ret = dcc_config_add(drvdata, addr, 1, false, curr_list);
+ if (ret)
+ return ret;
+
+ return dcc_rd_mod_wr_add(drvdata, mask, val, curr_list);
+}
+
+static int dcc_add_write(struct dcc_drvdata *drvdata, unsigned int addr,
+ unsigned int write_val, int apb_bus, int curr_list)
+{
+ struct dcc_config_entry *entry;
+
+ entry = devm_kzalloc(drvdata->dev, sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ return -ENOMEM;
+
+ entry->desc_type = DCC_WRITE_TYPE;
+ entry->base = addr & GENMASK(31, 4);
+ entry->offset = addr - entry->base;
+ entry->write_val = write_val;
+ entry->len = 1;
+ entry->apb_bus = apb_bus;
+ list_add_tail(&entry->list, &drvdata->cfg_head[curr_list]);
+
+ return 0;
+}
+
+static ssize_t dcc_config_add_write(struct dcc_drvdata *drvdata, char *buf, int curr_list)
+{
+ bool bus;
+ int nval;
+ unsigned int addr, write_val;
+ char apb_bus[4];
+
+ nval = sscanf(buf, "%x %x %3s", &addr, &write_val, apb_bus);
+
+ if (nval <= 1 || nval > 3)
+ return -EINVAL;
+
+ if (nval == 2)
+ bus = true;
+
+ if (nval == 3) {
+ if (!strcmp("apb", apb_bus))
+ bus = true;
+ else if (!strcmp("ahb", apb_bus))
+ bus = false;
+ else
+ return -EINVAL;
+ }
+
+ return dcc_add_write(drvdata, addr, write_val, bus, curr_list);
+}
+
+static int config_show(struct seq_file *m, void *data)
+{
+ struct dcc_drvdata *drvdata = m->private;
+ struct dcc_config_entry *entry;
+ int index = 0, curr_list;
+
+ curr_list = dcc_filp_curr_list(m->file);
+ if (curr_list < 0)
+ return curr_list;
+
+ mutex_lock(&drvdata->mutex);
+
+ list_for_each_entry(entry, &drvdata->cfg_head[curr_list], list) {
+ index++;
+ switch (entry->desc_type) {
+ case DCC_READ_WRITE_TYPE:
+ seq_printf(m, "RW mask: 0x%x, val: 0x%x\n index: 0x%x\n",
+ entry->mask, entry->write_val, index);
+ break;
+ case DCC_LOOP_TYPE:
+ seq_printf(m, "L index: 0x%x Loop: %d\n", index, entry->loop_cnt);
+ break;
+ case DCC_WRITE_TYPE:
+ seq_printf(m, "W Base:0x%x, Offset: 0x%x, val: 0x%x, APB: %d\n, Index: 0x%x\n",
+ entry->base, entry->offset, entry->write_val, entry->apb_bus,
+ index);
+ break;
+ case DCC_READ_TYPE:
+ seq_printf(m, "R Base:0x%x, Offset: 0x%x, len: 0x%x, APB: %d\n, Index: 0x%x\n",
+ entry->base, entry->offset, entry->len, entry->apb_bus, index);
+ }
+ }
+ mutex_unlock(&drvdata->mutex);
+ return 0;
+}
+
+static int config_open(struct inode *inode, struct file *file)
+{
+ struct dcc_drvdata *drvdata = inode->i_private;
+
+ return single_open(file, config_show, drvdata);
+}
+
+static ssize_t config_write(struct file *filp,
+ const char __user *user_buf, size_t count,
+ loff_t *ppos)
+{
+ int ret, curr_list;
+ char *token, buf[50];
+ char *bufp = buf;
+ char *delim = " ";
+ struct dcc_drvdata *drvdata = filp->private_data;
+
+ if (count > sizeof(buf) || count == 0)
+ return -EINVAL;
+
+ ret = copy_from_user(buf, user_buf, count);
+ if (ret)
+ return -EFAULT;
+
+ curr_list = dcc_filp_curr_list(filp);
+ if (curr_list < 0)
+ return curr_list;
+
+ if (buf[count - 1] == '\n')
+ buf[count - 1] = '\0';
+ else
+ return -EINVAL;
+
+ token = strsep(&bufp, delim);
+
+ if (!strcmp("R", token)) {
+ ret = dcc_config_add_read(drvdata, bufp, curr_list);
+ } else if (!strcmp("W", token)) {
+ ret = dcc_config_add_write(drvdata, bufp, curr_list);
+ } else if (!strcmp("RW", token)) {
+ ret = dcc_config_add_read_write(drvdata, bufp, curr_list);
+ } else if (!strcmp("L", token)) {
+ ret = dcc_config_add_loop(drvdata, bufp, curr_list);
+ } else {
+ dev_err(drvdata->dev, "%s is not a correct input\n", token);
+ return -EINVAL;
+ }
+
+ if (ret)
+ return ret;
+
+ return count;
+}
+
+static const struct file_operations config_fops = {
+ .open = config_open,
+ .read = seq_read,
+ .write = config_write,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static void dcc_delete_debug_dir(struct dcc_drvdata *drvdata)
+{
+ debugfs_remove_recursive(drvdata->dbg_dir);
+};
+
+static void dcc_create_debug_dir(struct dcc_drvdata *drvdata)
+{
+ int i;
+ char list_num[10];
+ struct dentry *list;
+ struct device *dev = drvdata->dev;
+
+ drvdata->dbg_dir = debugfs_create_dir(dev_name(dev), NULL);
+ if (IS_ERR(drvdata->dbg_dir)) {
+ pr_err("can't create debugfs dir\n");
+ return;
+ }
+
+ for (i = 0; i <= drvdata->nr_link_list; i++) {
+ sprintf(list_num, "%d", i);
+ list = debugfs_create_dir(list_num, drvdata->dbg_dir);
+ debugfs_create_file("enable", 0600, list, drvdata, &enable_fops);
+ debugfs_create_file("config", 0600, list, drvdata, &config_fops);
+ }
+
+ debugfs_create_file("trigger", 0200, drvdata->dbg_dir, drvdata, &trigger_fops);
+ debugfs_create_file("ready", 0400, drvdata->dbg_dir, drvdata, &ready_fops);
+ debugfs_create_file("config_reset", 0200, drvdata->dbg_dir,
+ drvdata, &config_reset_fops);
+}
+
+static ssize_t dcc_sram_read(struct file *file, char __user *data,
+ size_t len, loff_t *ppos)
+{
+ struct dcc_drvdata *drvdata = container_of(file->private_data, struct dcc_drvdata, sram_dev);
+ unsigned char *buf;
+
+ /* EOF check */
+ if (*ppos >= drvdata->ram_size)
+ return 0;
+
+ if ((*ppos + len) > drvdata->ram_size)
+ len = (drvdata->ram_size - *ppos);
+
+ buf = kzalloc(len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ memcpy_fromio(buf, drvdata->ram_base + *ppos, len);
+
+ if (copy_to_user(data, buf, len)) {
+ kfree(buf);
+ return -EFAULT;
+ }
+
+ *ppos += len;
+
+ kfree(buf);
+
+ return len;
+}
+
+static const struct file_operations dcc_sram_fops = {
+ .owner = THIS_MODULE,
+ .read = dcc_sram_read,
+ .llseek = no_llseek,
+};
+
+static int dcc_sram_dev_init(struct dcc_drvdata *drvdata)
+{
+ drvdata->sram_dev.minor = MISC_DYNAMIC_MINOR;
+ drvdata->sram_dev.name = DCC_SRAM_NODE;
+ drvdata->sram_dev.fops = &dcc_sram_fops;
+
+ return misc_register(&drvdata->sram_dev);
+}
+
+static void dcc_sram_dev_exit(struct dcc_drvdata *drvdata)
+{
+ misc_deregister(&drvdata->sram_dev);
+}
+
+static int dcc_probe(struct platform_device *pdev)
+{
+ u32 val;
+ int ret = 0, i;
+ struct device *dev = &pdev->dev;
+ struct dcc_drvdata *drvdata;
+ struct resource *res;
+
+ drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+ if (!drvdata)
+ return -ENOMEM;
+
+ drvdata->dev = &pdev->dev;
+ platform_set_drvdata(pdev, drvdata);
+
+ drvdata->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(drvdata->base))
+ return PTR_ERR(drvdata->base);
+
+ drvdata->ram_base = devm_platform_get_and_ioremap_resource(pdev, 1, &res);
+ if (IS_ERR(drvdata->ram_base))
+ return PTR_ERR(drvdata->ram_base);
+
+ drvdata->ram_size = resource_size(res);
+
+ drvdata->ram_offset = (size_t)of_device_get_match_data(&pdev->dev);
+
+ val = readl(drvdata->base + DCC_HW_INFO);
+
+ if (FIELD_GET(DCC_VER_INFO_MASK, val)) {
+ drvdata->mem_map_ver = 3;
+ drvdata->nr_link_list = readl(drvdata->base + DCC_LL_NUM_INFO);
+ if (!drvdata->nr_link_list)
+ return -EINVAL;
+ } else if ((val & DCC_VER_MASK2) == DCC_VER_MASK2) {
+ drvdata->mem_map_ver = 2;
+ drvdata->nr_link_list = readl(drvdata->base + DCC_LL_NUM_INFO);
+ if (!drvdata->nr_link_list)
+ return -EINVAL;
+ } else {
+ drvdata->mem_map_ver = 1;
+ drvdata->nr_link_list = DCC_MAX_LINK_LIST;
+ }
+
+ /* Either set the fixed loop offset or calculate
+ * it from the total number of words in dcc_sram.
+ * Max consecutive addresses dcc can loop is
+ * equivalent to the words in dcc_sram.
+ */
+ if (val & DCC_LOOP_OFFSET_MASK)
+ drvdata->loop_shift = DCC_FIX_LOOP_OFFSET;
+ else
+ drvdata->loop_shift = get_bitmask_order((drvdata->ram_offset +
+ drvdata->ram_size) / DCC_SRAM_WORD_LENGTH - 1);
+
+ mutex_init(&drvdata->mutex);
+
+ drvdata->enable_bitmap = devm_kcalloc(dev, BITS_TO_LONGS(drvdata->nr_link_list),
+ sizeof(*drvdata->enable_bitmap), GFP_KERNEL);
+ if (!drvdata->enable_bitmap)
+ return -ENOMEM;
+
+ drvdata->cfg_head = devm_kcalloc(dev, drvdata->nr_link_list,
+ sizeof(*drvdata->cfg_head), GFP_KERNEL);
+ if (!drvdata->cfg_head)
+ return -ENOMEM;
+
+ for (i = 0; i < drvdata->nr_link_list; i++)
+ INIT_LIST_HEAD(&drvdata->cfg_head[i]);
+
+ ret = dcc_sram_dev_init(drvdata);
+ if (ret) {
+ dev_err(drvdata->dev, "DCC: sram node not registered.\n");
+ return ret;
+ }
+
+ dcc_create_debug_dir(drvdata);
+
+ return 0;
+}
+
+static int dcc_remove(struct platform_device *pdev)
+{
+ struct dcc_drvdata *drvdata = platform_get_drvdata(pdev);
+
+ dcc_delete_debug_dir(drvdata);
+ dcc_sram_dev_exit(drvdata);
+ dcc_config_reset(drvdata);
+
+ return 0;
+}
+
+static const struct of_device_id dcc_match_table[] = {
+ { .compatible = "qcom,sc7180-dcc", .data = (void *)0x6000 },
+ { .compatible = "qcom,sc7280-dcc", .data = (void *)0x12000 },
+ { .compatible = "qcom,sdm845-dcc", .data = (void *)0x6000 },
+ { .compatible = "qcom,sm8150-dcc", .data = (void *)0x5000 },
+ { }
+};
+MODULE_DEVICE_TABLE(of, dcc_match_table);
+
+static struct platform_driver dcc_driver = {
+ .probe = dcc_probe,
+ .remove = dcc_remove,
+ .driver = {
+ .name = "qcom-dcc",
+ .of_match_table = dcc_match_table,
+ },
+};
+module_platform_driver(dcc_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Qualcomm Technologies Inc. DCC driver");