+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright (C) 2020 BAIKAL ELECTRONICS, JSC
- *
- * Authors:
- * Serge Semin <Sergey.Semin@baikalelectronics.ru>
- *
- * Baikal-T1 CM2 L2-cache Control Block driver.
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/bitfield.h>
-#include <linux/types.h>
-#include <linux/device.h>
-#include <linux/platform_device.h>
-#include <linux/regmap.h>
-#include <linux/mfd/syscon.h>
-#include <linux/sysfs.h>
-#include <linux/of.h>
-
-#define L2_CTL_REG 0x028
-#define L2_CTL_DATA_STALL_FLD 0
-#define L2_CTL_DATA_STALL_MASK GENMASK(1, L2_CTL_DATA_STALL_FLD)
-#define L2_CTL_TAG_STALL_FLD 2
-#define L2_CTL_TAG_STALL_MASK GENMASK(3, L2_CTL_TAG_STALL_FLD)
-#define L2_CTL_WS_STALL_FLD 4
-#define L2_CTL_WS_STALL_MASK GENMASK(5, L2_CTL_WS_STALL_FLD)
-#define L2_CTL_SET_CLKRATIO BIT(13)
-#define L2_CTL_CLKRATIO_LOCK BIT(31)
-
-#define L2_CTL_STALL_MIN 0
-#define L2_CTL_STALL_MAX 3
-#define L2_CTL_STALL_SET_DELAY_US 1
-#define L2_CTL_STALL_SET_TOUT_US 1000
-
-/*
- * struct l2_ctl - Baikal-T1 L2 Control block private data.
- * @dev: Pointer to the device structure.
- * @sys_regs: Baikal-T1 System Controller registers map.
- */
-struct l2_ctl {
- struct device *dev;
-
- struct regmap *sys_regs;
-};
-
-/*
- * enum l2_ctl_stall - Baikal-T1 L2-cache-RAM stall identifier.
- * @L2_WSSTALL: Way-select latency.
- * @L2_TAGSTALL: Tag latency.
- * @L2_DATASTALL: Data latency.
- */
-enum l2_ctl_stall {
- L2_WS_STALL,
- L2_TAG_STALL,
- L2_DATA_STALL
-};
-
-/*
- * struct l2_ctl_device_attribute - Baikal-T1 L2-cache device attribute.
- * @dev_attr: Actual sysfs device attribute.
- * @id: L2-cache stall field identifier.
- */
-struct l2_ctl_device_attribute {
- struct device_attribute dev_attr;
- enum l2_ctl_stall id;
-};
-
-#define to_l2_ctl_dev_attr(_dev_attr) \
- container_of(_dev_attr, struct l2_ctl_device_attribute, dev_attr)
-
-#define L2_CTL_ATTR_RW(_name, _prefix, _id) \
- struct l2_ctl_device_attribute l2_ctl_attr_##_name = \
- { __ATTR(_name, 0644, _prefix##_show, _prefix##_store), _id }
-
-static int l2_ctl_get_latency(struct l2_ctl *l2, enum l2_ctl_stall id, u32 *val)
-{
- u32 data = 0;
- int ret;
-
- ret = regmap_read(l2->sys_regs, L2_CTL_REG, &data);
- if (ret)
- return ret;
-
- switch (id) {
- case L2_WS_STALL:
- *val = FIELD_GET(L2_CTL_WS_STALL_MASK, data);
- break;
- case L2_TAG_STALL:
- *val = FIELD_GET(L2_CTL_TAG_STALL_MASK, data);
- break;
- case L2_DATA_STALL:
- *val = FIELD_GET(L2_CTL_DATA_STALL_MASK, data);
- break;
- default:
- return -EINVAL;
- }
-
- return 0;
-}
-
-static int l2_ctl_set_latency(struct l2_ctl *l2, enum l2_ctl_stall id, u32 val)
-{
- u32 mask = 0, data = 0;
- int ret;
-
- val = clamp_val(val, L2_CTL_STALL_MIN, L2_CTL_STALL_MAX);
-
- switch (id) {
- case L2_WS_STALL:
- data = FIELD_PREP(L2_CTL_WS_STALL_MASK, val);
- mask = L2_CTL_WS_STALL_MASK;
- break;
- case L2_TAG_STALL:
- data = FIELD_PREP(L2_CTL_TAG_STALL_MASK, val);
- mask = L2_CTL_TAG_STALL_MASK;
- break;
- case L2_DATA_STALL:
- data = FIELD_PREP(L2_CTL_DATA_STALL_MASK, val);
- mask = L2_CTL_DATA_STALL_MASK;
- break;
- default:
- return -EINVAL;
- }
-
- data |= L2_CTL_SET_CLKRATIO;
- mask |= L2_CTL_SET_CLKRATIO;
-
- ret = regmap_update_bits(l2->sys_regs, L2_CTL_REG, mask, data);
- if (ret)
- return ret;
-
- return regmap_read_poll_timeout(l2->sys_regs, L2_CTL_REG, data,
- data & L2_CTL_CLKRATIO_LOCK,
- L2_CTL_STALL_SET_DELAY_US,
- L2_CTL_STALL_SET_TOUT_US);
-}
-
-static void l2_ctl_clear_data(void *data)
-{
- struct l2_ctl *l2 = data;
- struct platform_device *pdev = to_platform_device(l2->dev);
-
- platform_set_drvdata(pdev, NULL);
-}
-
-static struct l2_ctl *l2_ctl_create_data(struct platform_device *pdev)
-{
- struct device *dev = &pdev->dev;
- struct l2_ctl *l2;
- int ret;
-
- l2 = devm_kzalloc(dev, sizeof(*l2), GFP_KERNEL);
- if (!l2)
- return ERR_PTR(-ENOMEM);
-
- ret = devm_add_action(dev, l2_ctl_clear_data, l2);
- if (ret) {
- dev_err(dev, "Can't add L2 CTL data clear action\n");
- return ERR_PTR(ret);
- }
-
- l2->dev = dev;
- platform_set_drvdata(pdev, l2);
-
- return l2;
-}
-
-static int l2_ctl_find_sys_regs(struct l2_ctl *l2)
-{
- l2->sys_regs = syscon_node_to_regmap(l2->dev->of_node->parent);
- if (IS_ERR(l2->sys_regs)) {
- dev_err(l2->dev, "Couldn't get L2 CTL register map\n");
- return PTR_ERR(l2->sys_regs);
- }
-
- return 0;
-}
-
-static int l2_ctl_of_parse_property(struct l2_ctl *l2, enum l2_ctl_stall id,
- const char *propname)
-{
- int ret = 0;
- u32 data;
-
- if (!of_property_read_u32(l2->dev->of_node, propname, &data)) {
- ret = l2_ctl_set_latency(l2, id, data);
- if (ret)
- dev_err(l2->dev, "Invalid value of '%s'\n", propname);
- }
-
- return ret;
-}
-
-static int l2_ctl_of_parse(struct l2_ctl *l2)
-{
- int ret;
-
- ret = l2_ctl_of_parse_property(l2, L2_WS_STALL, "baikal,l2-ws-latency");
- if (ret)
- return ret;
-
- ret = l2_ctl_of_parse_property(l2, L2_TAG_STALL, "baikal,l2-tag-latency");
- if (ret)
- return ret;
-
- return l2_ctl_of_parse_property(l2, L2_DATA_STALL,
- "baikal,l2-data-latency");
-}
-
-static ssize_t l2_ctl_latency_show(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct l2_ctl_device_attribute *devattr = to_l2_ctl_dev_attr(attr);
- struct l2_ctl *l2 = dev_get_drvdata(dev);
- u32 data;
- int ret;
-
- ret = l2_ctl_get_latency(l2, devattr->id, &data);
- if (ret)
- return ret;
-
- return sysfs_emit(buf, "%u\n", data);
-}
-
-static ssize_t l2_ctl_latency_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
-{
- struct l2_ctl_device_attribute *devattr = to_l2_ctl_dev_attr(attr);
- struct l2_ctl *l2 = dev_get_drvdata(dev);
- u32 data;
- int ret;
-
- if (kstrtouint(buf, 0, &data) < 0)
- return -EINVAL;
-
- ret = l2_ctl_set_latency(l2, devattr->id, data);
- if (ret)
- return ret;
-
- return count;
-}
-
-static L2_CTL_ATTR_RW(l2_ws_latency, l2_ctl_latency, L2_WS_STALL);
-static L2_CTL_ATTR_RW(l2_tag_latency, l2_ctl_latency, L2_TAG_STALL);
-static L2_CTL_ATTR_RW(l2_data_latency, l2_ctl_latency, L2_DATA_STALL);
-
-static struct attribute *l2_ctl_sysfs_attrs[] = {
- &l2_ctl_attr_l2_ws_latency.dev_attr.attr,
- &l2_ctl_attr_l2_tag_latency.dev_attr.attr,
- &l2_ctl_attr_l2_data_latency.dev_attr.attr,
- NULL
-};
-ATTRIBUTE_GROUPS(l2_ctl_sysfs);
-
-static void l2_ctl_remove_sysfs(void *data)
-{
- struct l2_ctl *l2 = data;
-
- device_remove_groups(l2->dev, l2_ctl_sysfs_groups);
-}
-
-static int l2_ctl_init_sysfs(struct l2_ctl *l2)
-{
- int ret;
-
- ret = device_add_groups(l2->dev, l2_ctl_sysfs_groups);
- if (ret) {
- dev_err(l2->dev, "Failed to create L2 CTL sysfs nodes\n");
- return ret;
- }
-
- ret = devm_add_action_or_reset(l2->dev, l2_ctl_remove_sysfs, l2);
- if (ret)
- dev_err(l2->dev, "Can't add L2 CTL sysfs remove action\n");
-
- return ret;
-}
-
-static int l2_ctl_probe(struct platform_device *pdev)
-{
- struct l2_ctl *l2;
- int ret;
-
- l2 = l2_ctl_create_data(pdev);
- if (IS_ERR(l2))
- return PTR_ERR(l2);
-
- ret = l2_ctl_find_sys_regs(l2);
- if (ret)
- return ret;
-
- ret = l2_ctl_of_parse(l2);
- if (ret)
- return ret;
-
- ret = l2_ctl_init_sysfs(l2);
- if (ret)
- return ret;
-
- return 0;
-}
-
-static const struct of_device_id l2_ctl_of_match[] = {
- { .compatible = "baikal,bt1-l2-ctl" },
- { }
-};
-MODULE_DEVICE_TABLE(of, l2_ctl_of_match);
-
-static struct platform_driver l2_ctl_driver = {
- .probe = l2_ctl_probe,
- .driver = {
- .name = "bt1-l2-ctl",
- .of_match_table = l2_ctl_of_match
- }
-};
-module_platform_driver(l2_ctl_driver);
-
-MODULE_AUTHOR("Serge Semin <Sergey.Semin@baikalelectronics.ru>");
-MODULE_DESCRIPTION("Baikal-T1 L2-cache driver");
projects / thirdparty / kernel / linux.git / commitdiff
