From fa0321ba51ddff78ebe3c7c945830a85c987e3ed Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Fri, 12 Aug 2022 15:25:31 -0700 Subject: [PATCH 1/3] dt-bindings: memory-controller: Document Broadcom STB MEMC Document the Broadcom STB memory controller which is a trivial binding for now with a set of compatible strings and single register. Since we introduce this binding, the section in Documentation/devicetree/bindings/arm/bcm/brcm,brcmstb.txt is removed and this binding is referenced instead. Reviewed-by: Rob Herring Signed-off-by: Florian Fainelli [krzk: correct path in brcm,brcmstb.txt] Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20220812222533.2428033-2-f.fainelli@gmail.com --- .../bindings/arm/bcm/brcm,brcmstb.txt | 11 +--- .../brcm,brcmstb-memc-ddr.yaml | 52 +++++++++++++++++++ 2 files changed, 54 insertions(+), 9 deletions(-) create mode 100644 Documentation/devicetree/bindings/memory-controllers/brcm,brcmstb-memc-ddr.yaml diff --git a/Documentation/devicetree/bindings/arm/bcm/brcm,brcmstb.txt b/Documentation/devicetree/bindings/arm/bcm/brcm,brcmstb.txt index 104cc9b41df4..071421dbc4d0 100644 --- a/Documentation/devicetree/bindings/arm/bcm/brcm,brcmstb.txt +++ b/Documentation/devicetree/bindings/arm/bcm/brcm,brcmstb.txt @@ -187,15 +187,8 @@ Required properties: Sequencer DRAM parameters and control registers. Used for Self-Refresh Power-Down (SRPD), among other things. -Required properties: -- compatible : should contain one of these - "brcm,brcmstb-memc-ddr-rev-b.2.1" - "brcm,brcmstb-memc-ddr-rev-b.2.2" - "brcm,brcmstb-memc-ddr-rev-b.2.3" - "brcm,brcmstb-memc-ddr-rev-b.3.0" - "brcm,brcmstb-memc-ddr-rev-b.3.1" - "brcm,brcmstb-memc-ddr" -- reg : the MEMC DDR register range +See Documentation/devicetree/bindings/memory-controllers/brcm,brcmstb-memc-ddr.yaml for a +full list of supported compatible strings and properties. Example: diff --git a/Documentation/devicetree/bindings/memory-controllers/brcm,brcmstb-memc-ddr.yaml b/Documentation/devicetree/bindings/memory-controllers/brcm,brcmstb-memc-ddr.yaml new file mode 100644 index 000000000000..4b072c879b02 --- /dev/null +++ b/Documentation/devicetree/bindings/memory-controllers/brcm,brcmstb-memc-ddr.yaml @@ -0,0 +1,52 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/memory-controllers/brcm,brcmstb-memc-ddr.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Memory controller (MEMC) for Broadcom STB + +maintainers: + - Florian Fainelli + +properties: + compatible: + items: + - enum: + - brcm,brcmstb-memc-ddr-rev-b.1.x + - brcm,brcmstb-memc-ddr-rev-b.2.0 + - brcm,brcmstb-memc-ddr-rev-b.2.1 + - brcm,brcmstb-memc-ddr-rev-b.2.2 + - brcm,brcmstb-memc-ddr-rev-b.2.3 + - brcm,brcmstb-memc-ddr-rev-b.2.5 + - brcm,brcmstb-memc-ddr-rev-b.2.6 + - brcm,brcmstb-memc-ddr-rev-b.2.7 + - brcm,brcmstb-memc-ddr-rev-b.2.8 + - brcm,brcmstb-memc-ddr-rev-b.3.0 + - brcm,brcmstb-memc-ddr-rev-b.3.1 + - brcm,brcmstb-memc-ddr-rev-c.1.0 + - brcm,brcmstb-memc-ddr-rev-c.1.1 + - brcm,brcmstb-memc-ddr-rev-c.1.2 + - brcm,brcmstb-memc-ddr-rev-c.1.3 + - brcm,brcmstb-memc-ddr-rev-c.1.4 + - const: brcm,brcmstb-memc-ddr + + reg: + maxItems: 1 + + clock-frequency: + description: DDR PHY frequency in Hz + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + memory-controller@9902000 { + compatible = "brcm,brcmstb-memc-ddr-rev-c.1.1", "brcm,brcmstb-memc-ddr"; + reg = <0x9902000 0x600>; + clock-frequency = <2133000000>; + }; From e3a1b9245ef72f3b9362816dffd6a08b27db10af Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Fri, 12 Aug 2022 15:25:32 -0700 Subject: [PATCH 2/3] Documentation: sysfs: Document Broadcom STB memc sysfs knobs Document the "srpd" and "frequency" sysfs attributes exposed by the brcmstb_memc driver. Signed-off-by: Florian Fainelli Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20220812222533.2428033-3-f.fainelli@gmail.com --- .../ABI/testing/sysfs-platform-brcmstb-memc | 15 +++++++++++++++ 1 file changed, 15 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-platform-brcmstb-memc diff --git a/Documentation/ABI/testing/sysfs-platform-brcmstb-memc b/Documentation/ABI/testing/sysfs-platform-brcmstb-memc new file mode 100644 index 000000000000..2f2b750ac2fd --- /dev/null +++ b/Documentation/ABI/testing/sysfs-platform-brcmstb-memc @@ -0,0 +1,15 @@ +What: /sys/bus/platform/devices/*/srpd +Date: July 2022 +KernelVersion: 5.21 +Contact: Florian Fainelli +Description: + Self Refresh Power Down (SRPD) inactivity timeout counted in + internal DDR controller clock cycles. Possible values range + from 0 (disable inactivity timeout) to 65535 (0xffff). + +What: /sys/bus/platform/devices/*/frequency +Date: July 2022 +KernelVersion: 5.21 +Contact: Florian Fainelli +Description: + DDR PHY frequency in Hz. From a4be90ff7a7d22a5a781ed2bb3c2d4b2f535a515 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Fri, 12 Aug 2022 15:25:33 -0700 Subject: [PATCH 3/3] memory: brcmstb_memc: Add Broadcom STB memory controller driver Add support for configuring the Self Refresh Power Down (SRPD) inactivity timeout on Broadcom STB chips. This is used to conserve power when the DRAM activity is reduced. Signed-off-by: Florian Fainelli Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20220812222533.2428033-4-f.fainelli@gmail.com --- drivers/memory/Kconfig | 9 + drivers/memory/Makefile | 1 + drivers/memory/brcmstb_memc.c | 301 ++++++++++++++++++++++++++++++++++ 3 files changed, 311 insertions(+) create mode 100644 drivers/memory/brcmstb_memc.c 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 +#include +#include +#include +#include +#include + +#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");