diff options
Diffstat (limited to 'drivers/memory')
| -rw-r--r-- | drivers/memory/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/memory/Makefile | 1 | ||||
| -rw-r--r-- | drivers/memory/brcmstb_memc.c | 301 |
3 files changed, 311 insertions, 0 deletions
diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig index ac1a411648d8..fac290e48e0b 100644 --- a/drivers/memory/Kconfig +++ b/drivers/memory/Kconfig @@ -66,6 +66,15 @@ config BRCMSTB_DPFE for the DRAM's temperature. Slower refresh rate means cooler RAM, higher refresh rate means hotter RAM. +config BRCMSTB_MEMC + tristate "Broadcom STB MEMC driver" + default ARCH_BRCMSTB + depends on ARCH_BRCMSTB || COMPILE_TEST + help + This driver provides a way to configure the Broadcom STB memory + controller and specifically control the Self Refresh Power Down + (SRPD) inactivity timeout. + config BT1_L2_CTL bool "Baikal-T1 CM2 L2-RAM Cache Control Block" depends on MIPS_BAIKAL_T1 || COMPILE_TEST diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile index bc7663ed1c25..e148f636c082 100644 --- a/drivers/memory/Makefile +++ b/drivers/memory/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_ARM_PL172_MPMC) += pl172.o obj-$(CONFIG_ATMEL_SDRAMC) += atmel-sdramc.o obj-$(CONFIG_ATMEL_EBI) += atmel-ebi.o obj-$(CONFIG_BRCMSTB_DPFE) += brcmstb_dpfe.o +obj-$(CONFIG_BRCMSTB_MEMC) += brcmstb_memc.o obj-$(CONFIG_BT1_L2_CTL) += bt1-l2-ctl.o obj-$(CONFIG_TI_AEMIF) += ti-aemif.o obj-$(CONFIG_TI_EMIF) += emif.o diff --git a/drivers/memory/brcmstb_memc.c b/drivers/memory/brcmstb_memc.c new file mode 100644 index 000000000000..233a53f5bce1 --- /dev/null +++ b/drivers/memory/brcmstb_memc.c @@ -0,0 +1,301 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * DDR Self-Refresh Power Down (SRPD) support for Broadcom STB SoCs + * + */ + +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> + +#define REG_MEMC_CNTRLR_CONFIG 0x00 +#define CNTRLR_CONFIG_LPDDR4_SHIFT 5 +#define CNTRLR_CONFIG_MASK 0xf +#define REG_MEMC_SRPD_CFG_21 0x20 +#define REG_MEMC_SRPD_CFG_20 0x34 +#define REG_MEMC_SRPD_CFG_1x 0x3c +#define INACT_COUNT_SHIFT 0 +#define INACT_COUNT_MASK 0xffff +#define SRPD_EN_SHIFT 16 + +struct brcmstb_memc_data { + u32 srpd_offset; +}; + +struct brcmstb_memc { + struct device *dev; + void __iomem *ddr_ctrl; + unsigned int timeout_cycles; + u32 frequency; + u32 srpd_offset; +}; + +static int brcmstb_memc_uses_lpddr4(struct brcmstb_memc *memc) +{ + void __iomem *config = memc->ddr_ctrl + REG_MEMC_CNTRLR_CONFIG; + u32 reg; + + reg = readl_relaxed(config) & CNTRLR_CONFIG_MASK; + + return reg == CNTRLR_CONFIG_LPDDR4_SHIFT; +} + +static int brcmstb_memc_srpd_config(struct brcmstb_memc *memc, + unsigned int cycles) +{ + void __iomem *cfg = memc->ddr_ctrl + memc->srpd_offset; + u32 val; + + /* Max timeout supported in HW */ + if (cycles > INACT_COUNT_MASK) + return -EINVAL; + + memc->timeout_cycles = cycles; + + val = (cycles << INACT_COUNT_SHIFT) & INACT_COUNT_MASK; + if (cycles) + val |= BIT(SRPD_EN_SHIFT); + + writel_relaxed(val, cfg); + /* Ensure the write is committed to the controller */ + (void)readl_relaxed(cfg); + + return 0; +} + +static ssize_t frequency_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct brcmstb_memc *memc = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", memc->frequency); +} + +static ssize_t srpd_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct brcmstb_memc *memc = dev_get_drvdata(dev); + + return sprintf(buf, "%d\n", memc->timeout_cycles); +} + +static ssize_t srpd_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct brcmstb_memc *memc = dev_get_drvdata(dev); + unsigned int val; + int ret; + + /* + * Cannot change the inactivity timeout on LPDDR4 chips because the + * dynamic tuning process will also get affected by the inactivity + * timeout, thus making it non functional. + */ + if (brcmstb_memc_uses_lpddr4(memc)) + return -EOPNOTSUPP; + + ret = kstrtouint(buf, 10, &val); + if (ret < 0) + return ret; + + ret = brcmstb_memc_srpd_config(memc, val); + if (ret) + return ret; + + return count; +} + +static DEVICE_ATTR_RO(frequency); +static DEVICE_ATTR_RW(srpd); + +static struct attribute *dev_attrs[] = { + &dev_attr_frequency.attr, + &dev_attr_srpd.attr, + NULL, +}; + +static struct attribute_group dev_attr_group = { + .attrs = dev_attrs, +}; + +static const struct of_device_id brcmstb_memc_of_match[]; + +static int brcmstb_memc_probe(struct platform_device *pdev) +{ + const struct brcmstb_memc_data *memc_data; + const struct of_device_id *of_id; + struct device *dev = &pdev->dev; + struct brcmstb_memc *memc; + int ret; + + memc = devm_kzalloc(dev, sizeof(*memc), GFP_KERNEL); + if (!memc) + return -ENOMEM; + + dev_set_drvdata(dev, memc); + + of_id = of_match_device(brcmstb_memc_of_match, dev); + memc_data = of_id->data; + memc->srpd_offset = memc_data->srpd_offset; + + memc->ddr_ctrl = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(memc->ddr_ctrl)) + return PTR_ERR(memc->ddr_ctrl); + + of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &memc->frequency); + + ret = sysfs_create_group(&dev->kobj, &dev_attr_group); + if (ret) + return ret; + + return 0; +} + +static int brcmstb_memc_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + + sysfs_remove_group(&dev->kobj, &dev_attr_group); + + return 0; +} + +enum brcmstb_memc_hwtype { + BRCMSTB_MEMC_V21, + BRCMSTB_MEMC_V20, + BRCMSTB_MEMC_V1X, +}; + +static const struct brcmstb_memc_data brcmstb_memc_versions[] = { + { .srpd_offset = REG_MEMC_SRPD_CFG_21 }, + { .srpd_offset = REG_MEMC_SRPD_CFG_20 }, + { .srpd_offset = REG_MEMC_SRPD_CFG_1x }, +}; + +static const struct of_device_id brcmstb_memc_of_match[] = { + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.1.x", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V1X] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.2.0", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V20] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.2.1", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.2.2", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.2.3", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.2.5", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.2.6", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.2.7", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.2.8", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.3.0", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-b.3.1", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-c.1.0", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-c.1.1", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-c.1.2", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-c.1.3", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + { + .compatible = "brcm,brcmstb-memc-ddr-rev-c.1.4", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V21] + }, + /* default to the original offset */ + { + .compatible = "brcm,brcmstb-memc-ddr", + .data = &brcmstb_memc_versions[BRCMSTB_MEMC_V1X] + }, + {} +}; + +static int brcmstb_memc_suspend(struct device *dev) +{ + struct brcmstb_memc *memc = dev_get_drvdata(dev); + void __iomem *cfg = memc->ddr_ctrl + memc->srpd_offset; + u32 val; + + if (memc->timeout_cycles == 0) + return 0; + + /* + * Disable SRPD prior to suspending the system since that can + * cause issues with other memory clients managed by the ARM + * trusted firmware to access memory. + */ + val = readl_relaxed(cfg); + val &= ~BIT(SRPD_EN_SHIFT); + writel_relaxed(val, cfg); + /* Ensure the write is committed to the controller */ + (void)readl_relaxed(cfg); + + return 0; +} + +static int brcmstb_memc_resume(struct device *dev) +{ + struct brcmstb_memc *memc = dev_get_drvdata(dev); + + if (memc->timeout_cycles == 0) + return 0; + + return brcmstb_memc_srpd_config(memc, memc->timeout_cycles); +} + +static DEFINE_SIMPLE_DEV_PM_OPS(brcmstb_memc_pm_ops, brcmstb_memc_suspend, + brcmstb_memc_resume); + +static struct platform_driver brcmstb_memc_driver = { + .probe = brcmstb_memc_probe, + .remove = brcmstb_memc_remove, + .driver = { + .name = "brcmstb_memc", + .of_match_table = brcmstb_memc_of_match, + .pm = pm_ptr(&brcmstb_memc_pm_ops), + }, +}; +module_platform_driver(brcmstb_memc_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Broadcom"); +MODULE_DESCRIPTION("DDR SRPD driver for Broadcom STB chips"); |