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-rw-r--r--Documentation/devicetree/bindings/bus/baikal,bt1-apb.yaml90
-rw-r--r--Documentation/devicetree/bindings/bus/baikal,bt1-axi.yaml107
-rw-r--r--drivers/bus/Kconfig30
-rw-r--r--drivers/bus/Makefile2
-rw-r--r--drivers/bus/bt1-apb.c422
-rw-r--r--drivers/bus/bt1-axi.c320
-rw-r--r--drivers/memory/Kconfig11
-rw-r--r--drivers/memory/Makefile1
-rw-r--r--drivers/memory/bt1-l2-ctl.c322
9 files changed, 1305 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/bus/baikal,bt1-apb.yaml b/Documentation/devicetree/bindings/bus/baikal,bt1-apb.yaml
new file mode 100644
index 000000000000..d6a3b71ea835
--- /dev/null
+++ b/Documentation/devicetree/bindings/bus/baikal,bt1-apb.yaml
@@ -0,0 +1,90 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) 2020 BAIKAL ELECTRONICS, JSC
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/bus/baikal,bt1-apb.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Baikal-T1 APB-bus
+
+maintainers:
+ - Serge Semin <fancer.lancer@gmail.com>
+
+description: |
+ Baikal-T1 CPU or DMAC MMIO requests are handled by the AMBA 3 AXI Interconnect
+ which routes them to the AXI-APB bridge. This interface is a single master
+ multiple slaves bus in turn serializing IO accesses and routing them to the
+ addressed APB slave devices. In case of any APB protocol collisions, slave
+ device not responding on timeout an IRQ is raised with an erroneous address
+ reported to the APB terminator (APB Errors Handler Block).
+
+allOf:
+ - $ref: /schemas/simple-bus.yaml#
+
+properties:
+ compatible:
+ contains:
+ const: baikal,bt1-apb
+
+ reg:
+ items:
+ - description: APB EHB MMIO registers
+ - description: APB MMIO region with no any device mapped
+
+ reg-names:
+ items:
+ - const: ehb
+ - const: nodev
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ items:
+ - description: APB reference clock
+
+ clock-names:
+ items:
+ - const: pclk
+
+ resets:
+ items:
+ - description: APB domain reset line
+
+ reset-names:
+ items:
+ - const: prst
+
+unevaluatedProperties: false
+
+required:
+ - compatible
+ - reg
+ - reg-names
+ - interrupts
+ - clocks
+ - clock-names
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/mips-gic.h>
+
+ bus@1f059000 {
+ compatible = "baikal,bt1-apb", "simple-bus";
+ reg = <0 0x1f059000 0 0x1000>,
+ <0 0x1d000000 0 0x2040000>;
+ reg-names = "ehb", "nodev";
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ ranges;
+
+ interrupts = <GIC_SHARED 16 IRQ_TYPE_LEVEL_HIGH>;
+
+ clocks = <&ccu_sys 1>;
+ clock-names = "pclk";
+
+ resets = <&ccu_sys 1>;
+ reset-names = "prst";
+ };
+...
diff --git a/Documentation/devicetree/bindings/bus/baikal,bt1-axi.yaml b/Documentation/devicetree/bindings/bus/baikal,bt1-axi.yaml
new file mode 100644
index 000000000000..203bc0e5346b
--- /dev/null
+++ b/Documentation/devicetree/bindings/bus/baikal,bt1-axi.yaml
@@ -0,0 +1,107 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# Copyright (C) 2020 BAIKAL ELECTRONICS, JSC
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/bus/baikal,bt1-axi.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Baikal-T1 AXI-bus
+
+maintainers:
+ - Serge Semin <fancer.lancer@gmail.com>
+
+description: |
+ AXI3-bus is the main communication bus of Baikal-T1 SoC connecting all
+ high-speed peripheral IP-cores with RAM controller and with MIPS P5600
+ cores. Traffic arbitration is done by means of DW AXI Interconnect (so
+ called AXI Main Interconnect) routing IO requests from one block to
+ another: from CPU to SoC peripherals and between some SoC peripherals
+ (mostly between peripheral devices and RAM, but also between DMA and
+ some peripherals). In case of any protocol error, device not responding
+ an IRQ is raised and a faulty situation is reported to the AXI EHB
+ (Errors Handler Block) embedded on top of the DW AXI Interconnect and
+ accessible by means of the Baikal-T1 System Controller.
+
+allOf:
+ - $ref: /schemas/simple-bus.yaml#
+
+properties:
+ compatible:
+ contains:
+ const: baikal,bt1-axi
+
+ reg:
+ minItems: 1
+ items:
+ - description: Synopsys DesignWare AXI Interconnect QoS registers
+ - description: AXI EHB MMIO system controller registers
+
+ reg-names:
+ minItems: 1
+ items:
+ - const: qos
+ - const: ehb
+
+ '#interconnect-cells':
+ const: 1
+
+ syscon:
+ $ref: /schemas/types.yaml#definitions/phandle
+ description: Phandle to the Baikal-T1 System Controller DT node
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ items:
+ - description: Main Interconnect uplink reference clock
+
+ clock-names:
+ items:
+ - const: aclk
+
+ resets:
+ items:
+ - description: Main Interconnect reset line
+
+ reset-names:
+ items:
+ - const: arst
+
+unevaluatedProperties: false
+
+required:
+ - compatible
+ - reg
+ - reg-names
+ - syscon
+ - interrupts
+ - clocks
+ - clock-names
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/mips-gic.h>
+
+ bus@1f05a000 {
+ compatible = "baikal,bt1-axi", "simple-bus";
+ reg = <0 0x1f05a000 0 0x1000>,
+ <0 0x1f04d110 0 0x8>;
+ reg-names = "qos", "ehb";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ #interconnect-cells = <1>;
+
+ syscon = <&syscon>;
+
+ ranges;
+
+ interrupts = <GIC_SHARED 127 IRQ_TYPE_LEVEL_HIGH>;
+
+ clocks = <&ccu_axi 0>;
+ clock-names = "aclk";
+
+ resets = <&ccu_axi 0>;
+ reset-names = "arst";
+ };
+...
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 6d4e4497b59b..030f0e59f193 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -29,6 +29,36 @@ config BRCMSTB_GISB_ARB
arbiter. This driver provides timeout and target abort error handling
and internal bus master decoding.
+config BT1_APB
+ tristate "Baikal-T1 APB-bus driver"
+ depends on MIPS_BAIKAL_T1 || COMPILE_TEST
+ select REGMAP_MMIO
+ help
+ Baikal-T1 AXI-APB bridge is used to access the SoC subsystem CSRs.
+ IO requests are routed to this bus by means of the DW AMBA 3 AXI
+ Interconnect. In case of any APB protocol collisions, slave device
+ not responding on timeout an IRQ is raised with an erroneous address
+ reported to the APB terminator (APB Errors Handler Block). This
+ driver provides the interrupt handler to detect the erroneous
+ address, prints an error message about the address fault, updates an
+ errors counter. The counter and the APB-bus operations timeout can be
+ accessed via corresponding sysfs nodes.
+
+config BT1_AXI
+ tristate "Baikal-T1 AXI-bus driver"
+ depends on MIPS_BAIKAL_T1 || COMPILE_TEST
+ select MFD_SYSCON
+ help
+ AXI3-bus is the main communication bus connecting all high-speed
+ peripheral IP-cores with RAM controller and with MIPS P5600 cores on
+ Baikal-T1 SoC. Traffic arbitration is done by means of DW AMBA 3 AXI
+ Interconnect (so called AXI Main Interconnect) routing IO requests
+ from one SoC block to another. This driver provides a way to detect
+ any bus protocol errors and device not responding situations by
+ means of an embedded on top of the interconnect errors handler
+ block (EHB). AXI Interconnect QoS arbitration tuning is currently
+ unsupported.
+
config MOXTET
tristate "CZ.NIC Turris Mox module configuration bus"
depends on SPI_MASTER && OF
diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile
index 05f32cd694a4..08ccbfaf7705 100644
--- a/drivers/bus/Makefile
+++ b/drivers/bus/Makefile
@@ -13,6 +13,8 @@ obj-$(CONFIG_MOXTET) += moxtet.o
# DPAA2 fsl-mc bus
obj-$(CONFIG_FSL_MC_BUS) += fsl-mc/
+obj-$(CONFIG_BT1_APB) += bt1-apb.o
+obj-$(CONFIG_BT1_AXI) += bt1-axi.o
obj-$(CONFIG_IMX_WEIM) += imx-weim.o
obj-$(CONFIG_MIPS_CDMM) += mips_cdmm.o
obj-$(CONFIG_MVEBU_MBUS) += mvebu-mbus.o
diff --git a/drivers/bus/bt1-apb.c b/drivers/bus/bt1-apb.c
new file mode 100644
index 000000000000..abccd1dfc544
--- /dev/null
+++ b/drivers/bus/bt1-apb.c
@@ -0,0 +1,422 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 BAIKAL ELECTRONICS, JSC
+ *
+ * Authors:
+ * Serge Semin <Sergey.Semin@baikalelectronics.ru>
+ *
+ * Baikal-T1 APB-bus driver
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/atomic.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/nmi.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/clk.h>
+#include <linux/reset.h>
+#include <linux/time64.h>
+#include <linux/clk.h>
+#include <linux/sysfs.h>
+
+#define APB_EHB_ISR 0x00
+#define APB_EHB_ISR_PENDING BIT(0)
+#define APB_EHB_ISR_MASK BIT(1)
+#define APB_EHB_ADDR 0x04
+#define APB_EHB_TIMEOUT 0x08
+
+#define APB_EHB_TIMEOUT_MIN 0x000003FFU
+#define APB_EHB_TIMEOUT_MAX 0xFFFFFFFFU
+
+/*
+ * struct bt1_apb - Baikal-T1 APB EHB private data
+ * @dev: Pointer to the device structure.
+ * @regs: APB EHB registers map.
+ * @res: No-device error injection memory region.
+ * @irq: Errors IRQ number.
+ * @rate: APB-bus reference clock rate.
+ * @pclk: APB-reference clock.
+ * @prst: APB domain reset line.
+ * @count: Number of errors detected.
+ */
+struct bt1_apb {
+ struct device *dev;
+
+ struct regmap *regs;
+ void __iomem *res;
+ int irq;
+
+ unsigned long rate;
+ struct clk *pclk;
+
+ struct reset_control *prst;
+
+ atomic_t count;
+};
+
+static const struct regmap_config bt1_apb_regmap_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = APB_EHB_TIMEOUT,
+ .fast_io = true
+};
+
+static inline unsigned long bt1_apb_n_to_timeout_us(struct bt1_apb *apb, u32 n)
+{
+ u64 timeout = (u64)n * USEC_PER_SEC;
+
+ do_div(timeout, apb->rate);
+
+ return timeout;
+
+}
+
+static inline unsigned long bt1_apb_timeout_to_n_us(struct bt1_apb *apb,
+ unsigned long timeout)
+{
+ u64 n = (u64)timeout * apb->rate;
+
+ do_div(n, USEC_PER_SEC);
+
+ return n;
+
+}
+
+static irqreturn_t bt1_apb_isr(int irq, void *data)
+{
+ struct bt1_apb *apb = data;
+ u32 addr = 0;
+
+ regmap_read(apb->regs, APB_EHB_ADDR, &addr);
+
+ dev_crit_ratelimited(apb->dev,
+ "APB-bus fault %d: Slave access timeout at 0x%08x\n",
+ atomic_inc_return(&apb->count),
+ addr);
+
+ /*
+ * Print backtrace on each CPU. This might be pointless if the fault
+ * has happened on the same CPU as the IRQ handler is executed or
+ * the other core proceeded further execution despite the error.
+ * But if it's not, by looking at the trace we would get straight to
+ * the cause of the problem.
+ */
+ trigger_all_cpu_backtrace();
+
+ regmap_update_bits(apb->regs, APB_EHB_ISR, APB_EHB_ISR_PENDING, 0);
+
+ return IRQ_HANDLED;
+}
+
+static void bt1_apb_clear_data(void *data)
+{
+ struct bt1_apb *apb = data;
+ struct platform_device *pdev = to_platform_device(apb->dev);
+
+ platform_set_drvdata(pdev, NULL);
+}
+
+static struct bt1_apb *bt1_apb_create_data(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct bt1_apb *apb;
+ int ret;
+
+ apb = devm_kzalloc(dev, sizeof(*apb), GFP_KERNEL);
+ if (!apb)
+ return ERR_PTR(-ENOMEM);
+
+ ret = devm_add_action(dev, bt1_apb_clear_data, apb);
+ if (ret) {
+ dev_err(dev, "Can't add APB EHB data clear action\n");
+ return ERR_PTR(ret);
+ }
+
+ apb->dev = dev;
+ atomic_set(&apb->count, 0);
+ platform_set_drvdata(pdev, apb);
+
+ return apb;
+}
+
+static int bt1_apb_request_regs(struct bt1_apb *apb)
+{
+ struct platform_device *pdev = to_platform_device(apb->dev);
+ void __iomem *regs;
+
+ regs = devm_platform_ioremap_resource_byname(pdev, "ehb");
+ if (IS_ERR(regs)) {
+ dev_err(apb->dev, "Couldn't map APB EHB registers\n");
+ return PTR_ERR(regs);
+ }
+
+ apb->regs = devm_regmap_init_mmio(apb->dev, regs, &bt1_apb_regmap_cfg);
+ if (IS_ERR(apb->regs)) {
+ dev_err(apb->dev, "Couldn't create APB EHB regmap\n");
+ return PTR_ERR(apb->regs);
+ }
+
+ apb->res = devm_platform_ioremap_resource_byname(pdev, "nodev");
+ if (IS_ERR(apb->res)) {
+ dev_err(apb->dev, "Couldn't map reserved region\n");
+ return PTR_ERR(apb->res);
+ }
+
+ return 0;
+}
+
+static int bt1_apb_request_rst(struct bt1_apb *apb)
+{
+ int ret;
+
+ apb->prst = devm_reset_control_get_optional_exclusive(apb->dev, "prst");
+ if (IS_ERR(apb->prst)) {
+ dev_warn(apb->dev, "Couldn't get reset control line\n");
+ return PTR_ERR(apb->prst);
+ }
+
+ ret = reset_control_deassert(apb->prst);
+ if (ret)
+ dev_err(apb->dev, "Failed to deassert the reset line\n");
+
+ return ret;
+}
+
+static void bt1_apb_disable_clk(void *data)
+{
+ struct bt1_apb *apb = data;
+
+ clk_disable_unprepare(apb->pclk);
+}
+
+static int bt1_apb_request_clk(struct bt1_apb *apb)
+{
+ int ret;
+
+ apb->pclk = devm_clk_get(apb->dev, "pclk");
+ if (IS_ERR(apb->pclk)) {
+ dev_err(apb->dev, "Couldn't get APB clock descriptor\n");
+ return PTR_ERR(apb->pclk);
+ }
+
+ ret = clk_prepare_enable(apb->pclk);
+ if (ret) {
+ dev_err(apb->dev, "Couldn't enable the APB clock\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(apb->dev, bt1_apb_disable_clk, apb);
+ if (ret) {
+ dev_err(apb->dev, "Can't add APB EHB clocks disable action\n");
+ return ret;
+ }
+
+ apb->rate = clk_get_rate(apb->pclk);
+ if (!apb->rate) {
+ dev_err(apb->dev, "Invalid clock rate\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void bt1_apb_clear_irq(void *data)
+{
+ struct bt1_apb *apb = data;
+
+ regmap_update_bits(apb->regs, APB_EHB_ISR, APB_EHB_ISR_MASK, 0);
+}
+
+static int bt1_apb_request_irq(struct bt1_apb *apb)
+{
+ struct platform_device *pdev = to_platform_device(apb->dev);
+ int ret;
+
+ apb->irq = platform_get_irq(pdev, 0);
+ if (apb->irq < 0)
+ return apb->irq;
+
+ ret = devm_request_irq(apb->dev, apb->irq, bt1_apb_isr, IRQF_SHARED,
+ "bt1-apb", apb);
+ if (ret) {
+ dev_err(apb->dev, "Couldn't request APB EHB IRQ\n");
+ return ret;
+ }
+
+ ret = devm_add_action(apb->dev, bt1_apb_clear_irq, apb);
+ if (ret) {
+ dev_err(apb->dev, "Can't add APB EHB IRQs clear action\n");
+ return ret;
+ }
+
+ /* Unmask IRQ and clear it' pending flag. */
+ regmap_update_bits(apb->regs, APB_EHB_ISR,
+ APB_EHB_ISR_PENDING | APB_EHB_ISR_MASK,
+ APB_EHB_ISR_MASK);
+
+ return 0;
+}
+
+static ssize_t count_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct bt1_apb *apb = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&apb->count));
+}
+static DEVICE_ATTR_RO(count);
+
+static ssize_t timeout_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct bt1_apb *apb = dev_get_drvdata(dev);
+ unsigned long timeout;
+ int ret;
+ u32 n;
+
+ ret = regmap_read(apb->regs, APB_EHB_TIMEOUT, &n);
+ if (ret)
+ return ret;
+
+ timeout = bt1_apb_n_to_timeout_us(apb, n);
+
+ return scnprintf(buf, PAGE_SIZE, "%lu\n", timeout);
+}
+
+static ssize_t timeout_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct bt1_apb *apb = dev_get_drvdata(dev);
+ unsigned long timeout;
+ int ret;
+ u32 n;
+
+ if (kstrtoul(buf, 0, &timeout) < 0)
+ return -EINVAL;
+
+ n = bt1_apb_timeout_to_n_us(apb, timeout);
+ n = clamp(n, APB_EHB_TIMEOUT_MIN, APB_EHB_TIMEOUT_MAX);
+
+ ret = regmap_write(apb->regs, APB_EHB_TIMEOUT, n);
+
+ return ret ?: count;
+}
+static DEVICE_ATTR_RW(timeout);
+
+static ssize_t inject_error_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ return scnprintf(buf, PAGE_SIZE, "Error injection: nodev irq\n");
+}
+
+static ssize_t inject_error_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *data, size_t count)
+{
+ struct bt1_apb *apb = dev_get_drvdata(dev);
+
+ /*
+ * Either dummy read from the unmapped address in the APB IO area
+ * or manually set the IRQ status.
+ */
+ if (!strncmp(data, "nodev", 5))
+ readl(apb->res);
+ else if (!strncmp(data, "irq", 3))
+ regmap_update_bits(apb->regs, APB_EHB_ISR, APB_EHB_ISR_PENDING,
+ APB_EHB_ISR_PENDING);
+ else
+ return -EINVAL;
+
+ return count;
+}
+static DEVICE_ATTR_RW(inject_error);
+
+static struct attribute *bt1_apb_sysfs_attrs[] = {
+ &dev_attr_count.attr,
+ &dev_attr_timeout.attr,
+ &dev_attr_inject_error.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(bt1_apb_sysfs);
+
+static void bt1_apb_remove_sysfs(void *data)
+{
+ struct bt1_apb *apb = data;
+
+ device_remove_groups(apb->dev, bt1_apb_sysfs_groups);
+}
+
+static int bt1_apb_init_sysfs(struct bt1_apb *apb)
+{
+ int ret;
+
+ ret = device_add_groups(apb->dev, bt1_apb_sysfs_groups);
+ if (ret) {
+ dev_err(apb->dev, "Failed to create EHB APB sysfs nodes\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(apb->dev, bt1_apb_remove_sysfs, apb);
+ if (ret)
+ dev_err(apb->dev, "Can't add APB EHB sysfs remove action\n");
+
+ return ret;
+}
+
+static int bt1_apb_probe(struct platform_device *pdev)
+{
+ struct bt1_apb *apb;
+ int ret;
+
+ apb = bt1_apb_create_data(pdev);
+ if (IS_ERR(apb))
+ return PTR_ERR(apb);
+
+ ret = bt1_apb_request_regs(apb);
+ if (ret)
+ return ret;
+
+ ret = bt1_apb_request_rst(apb);
+ if (ret)
+ return ret;
+
+ ret = bt1_apb_request_clk(apb);
+ if (ret)
+ return ret;
+
+ ret = bt1_apb_request_irq(apb);
+ if (ret)
+ return ret;
+
+ ret = bt1_apb_init_sysfs(apb);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static const struct of_device_id bt1_apb_of_match[] = {
+ { .compatible = "baikal,bt1-apb" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, bt1_apb_of_match);
+
+static struct platform_driver bt1_apb_driver = {
+ .probe = bt1_apb_probe,
+ .driver = {
+ .name = "bt1-apb",
+ .of_match_table = bt1_apb_of_match
+ }
+};
+module_platform_driver(bt1_apb_driver);
+
+MODULE_AUTHOR("Serge Semin <Sergey.Semin@baikalelectronics.ru>");
+MODULE_DESCRIPTION("Baikal-T1 APB-bus driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/bus/bt1-axi.c b/drivers/bus/bt1-axi.c
new file mode 100644
index 000000000000..2005f9174118
--- /dev/null
+++ b/drivers/bus/bt1-axi.c
@@ -0,0 +1,320 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 BAIKAL ELECTRONICS, JSC
+ *
+ * Authors:
+ * Serge Semin <Sergey.Semin@baikalelectronics.ru>
+ *
+ * Baikal-T1 AXI-bus driver
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/bitfield.h>
+#include <linux/device.h>
+#include <linux/atomic.h>
+#include <linux/regmap.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/syscon.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/nmi.h>
+#include <linux/of.h>
+#include <linux/clk.h>
+#include <linux/reset.h>
+#include <linux/sysfs.h>
+
+#define BT1_AXI_WERRL 0x110
+#define BT1_AXI_WERRH 0x114
+#define BT1_AXI_WERRH_TYPE BIT(23)
+#define BT1_AXI_WERRH_ADDR_FLD 24
+#define BT1_AXI_WERRH_ADDR_MASK GENMASK(31, BT1_AXI_WERRH_ADDR_FLD)
+
+/*
+ * struct bt1_axi - Baikal-T1 AXI-bus private data
+ * @dev: Pointer to the device structure.
+ * @qos_regs: AXI Interconnect QoS tuning registers.
+ * @sys_regs: Baikal-T1 System Controller registers map.
+ * @irq: Errors IRQ number.
+ * @aclk: AXI reference clock.
+ * @arst: AXI Interconnect reset line.
+ * @count: Number of errors detected.
+ */
+struct bt1_axi {
+ struct device *dev;
+
+ void __iomem *qos_regs;
+ struct regmap *sys_regs;
+ int irq;
+
+ struct clk *aclk;
+
+ struct reset_control *arst;
+
+ atomic_t count;
+};
+
+static irqreturn_t bt1_axi_isr(int irq, void *data)
+{
+ struct bt1_axi *axi = data;
+ u32 low = 0, high = 0;
+
+ regmap_read(axi->sys_regs, BT1_AXI_WERRL, &low);
+ regmap_read(axi->sys_regs, BT1_AXI_WERRH, &high);
+
+ dev_crit_ratelimited(axi->dev,
+ "AXI-bus fault %d: %s at 0x%x%08x\n",
+ atomic_inc_return(&axi->count),
+ high & BT1_AXI_WERRH_TYPE ? "no slave" : "slave protocol error",
+ high, low);
+
+ /*
+ * Print backtrace on each CPU. This might be pointless if the fault
+ * has happened on the same CPU as the IRQ handler is executed or
+ * the other core proceeded further execution despite the error.
+ * But if it's not, by looking at the trace we would get straight to
+ * the cause of the problem.
+ */
+ trigger_all_cpu_backtrace();
+
+ return IRQ_HANDLED;
+}
+
+static void bt1_axi_clear_data(void *data)
+{
+ struct bt1_axi *axi = data;
+ struct platform_device *pdev = to_platform_device(axi->dev);
+
+ platform_set_drvdata(pdev, NULL);
+}
+
+static struct bt1_axi *bt1_axi_create_data(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct bt1_axi *axi;
+ int ret;
+
+ axi = devm_kzalloc(dev, sizeof(*axi), GFP_KERNEL);
+ if (!axi)
+ return ERR_PTR(-ENOMEM);
+
+ ret = devm_add_action(dev, bt1_axi_clear_data, axi);
+ if (ret) {
+ dev_err(dev, "Can't add AXI EHB data clear action\n");
+ return ERR_PTR(ret);
+ }
+
+ axi->dev = dev;
+ atomic_set(&axi->count, 0);
+ platform_set_drvdata(pdev, axi);
+
+ return axi;
+}
+
+static int bt1_axi_request_regs(struct bt1_axi *axi)
+{
+ struct platform_device *pdev = to_platform_device(axi->dev);
+ struct device *dev = axi->dev;
+
+ axi->sys_regs = syscon_regmap_lookup_by_phandle(dev->of_node, "syscon");
+ if (IS_ERR(axi->sys_regs)) {
+ dev_err(dev, "Couldn't find syscon registers\n");
+ return PTR_ERR(axi->sys_regs);
+ }
+
+ axi->qos_regs = devm_platform_ioremap_resource_byname(pdev, "qos");
+ if (IS_ERR(axi->qos_regs)) {
+ dev_err(dev, "Couldn't map AXI-bus QoS registers\n");
+ return PTR_ERR(axi->qos_regs);
+ }
+
+ return 0;
+}
+
+static int bt1_axi_request_rst(struct bt1_axi *axi)
+{
+ int ret;
+
+ axi->arst = devm_reset_control_get_optional_exclusive(axi->dev, "arst");
+ if (IS_ERR(axi->arst)) {
+ dev_warn(axi->dev, "Couldn't get reset control line\n");
+ return PTR_ERR(axi->arst);
+ }
+
+ ret = reset_control_deassert(axi->arst);
+ if (ret)
+ dev_err(axi->dev, "Failed to deassert the reset line\n");
+
+ return ret;
+}
+
+static void bt1_axi_disable_clk(void *data)
+{
+ struct bt1_axi *axi = data;
+
+ clk_disable_unprepare(axi->aclk);
+}
+
+static int bt1_axi_request_clk(struct bt1_axi *axi)
+{
+ int ret;
+
+ axi->aclk = devm_clk_get(axi->dev, "aclk");
+ if (IS_ERR(axi->aclk)) {
+ dev_err(axi->dev, "Couldn't get AXI Interconnect clock\n");
+ return PTR_ERR(axi->aclk);
+ }
+
+ ret = clk_prepare_enable(axi->aclk);
+ if (ret) {
+ dev_err(axi->dev, "Couldn't enable the AXI clock\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(axi->dev, bt1_axi_disable_clk, axi);
+ if (ret) {
+ dev_err(axi->dev, "Can't add AXI clock disable action\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int bt1_axi_request_irq(struct bt1_axi *axi)
+{
+ struct platform_device *pdev = to_platform_device(axi->dev);
+ int ret;
+
+ axi->irq = platform_get_irq(pdev, 0);
+ if (axi->irq < 0)
+ return axi->irq;
+
+ ret = devm_request_irq(axi->dev, axi->irq, bt1_axi_isr, IRQF_SHARED,
+ "bt1-axi", axi);
+ if (ret) {
+ dev_err(axi->dev, "Couldn't request AXI EHB IRQ\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static ssize_t count_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct bt1_axi *axi = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&axi->count));
+}
+static DEVICE_ATTR_RO(count);
+
+static ssize_t inject_error_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return scnprintf(buf, PAGE_SIZE, "Error injection: bus unaligned\n");
+}
+
+static ssize_t inject_error_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *data, size_t count)
+{
+ struct bt1_axi *axi = dev_get_drvdata(dev);
+
+ /*
+ * Performing unaligned read from the memory will cause the CM2 bus
+ * error while unaligned writing - the AXI bus write error handled
+ * by this driver.
+ */
+ if (!strncmp(data, "bus", 3))
+ readb(axi->qos_regs);
+ else if (!strncmp(data, "unaligned", 9))
+ writeb(0, axi->qos_regs);
+ else
+ return -EINVAL;
+
+ return count;
+}
+static DEVICE_ATTR_RW(inject_error);
+
+static struct attribute *bt1_axi_sysfs_attrs[] = {
+ &dev_attr_count.attr,
+ &dev_attr_inject_error.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(bt1_axi_sysfs);
+
+static void bt1_axi_remove_sysfs(void *data)
+{
+ struct bt1_axi *axi = data;
+
+ device_remove_groups(axi->dev, bt1_axi_sysfs_groups);
+}
+
+static int bt1_axi_init_sysfs(struct bt1_axi *axi)
+{
+ int ret;
+
+ ret = device_add_groups(axi->dev, bt1_axi_sysfs_groups);
+ if (ret) {
+ dev_err(axi->dev, "Failed to add sysfs files group\n");
+ return ret;
+ }
+
+ ret = devm_add_action_or_reset(axi->dev, bt1_axi_remove_sysfs, axi);
+ if (ret)
+ dev_err(axi->dev, "Can't add AXI EHB sysfs remove action\n");
+
+ return ret;
+}
+
+static int bt1_axi_probe(struct platform_device *pdev)
+{
+ struct bt1_axi *axi;
+ int ret;
+
+ axi = bt1_axi_create_data(pdev);
+ if (IS_ERR(axi))
+ return PTR_ERR(axi);
+
+ ret = bt1_axi_request_regs(axi);
+ if (ret)
+ return ret;
+
+ ret = bt1_axi_request_rst(axi);
+ if (ret)
+ return ret;
+
+ ret = bt1_axi_request_clk(axi);
+ if (ret)
+ return ret;
+
+ ret = bt1_axi_request_irq(axi);
+ if (ret)
+ return ret;
+
+ ret = bt1_axi_init_sysfs(axi);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static const struct of_device_id bt1_axi_of_match[] = {
+ { .compatible = "baikal,bt1-axi" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, bt1_axi_of_match);
+
+static struct platform_driver bt1_axi_driver = {
+ .probe = bt1_axi_probe,
+ .driver = {
+ .name = "bt1-axi",
+ .of_match_table = bt1_axi_of_match
+ }
+};
+module_platform_driver(bt1_axi_driver);
+
+MODULE_AUTHOR("Serge Semin <Sergey.Semin@baikalelectronics.ru>");
+MODULE_DESCRIPTION("Baikal-T1 AXI-bus driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index 9bddca292330..04368ee2a809 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -46,6 +46,17 @@ config ATMEL_EBI
tree is used. This bus supports NANDs, external ethernet controller,
SRAMs, ATA devices, etc.
+config BT1_L2_CTL
+ bool "Baikal-T1 CM2 L2-RAM Cache Control Block"
+ depends on MIPS_BAIKAL_T1 || COMPILE_TEST
+ select MFD_SYSCON
+ help
+ Baikal-T1 CPU is based on the MIPS P5600 Warrior IP-core. The CPU
+ resides Coherency Manager v2 with embedded 1MB L2-cache. It's
+ possible to tune the L2 cache performance up by setting the data,
+ tags and way-select latencies of RAM access. This driver provides a
+ dt properties-based and sysfs interface for it.
+
config TI_AEMIF
tristate "Texas Instruments AEMIF driver"
depends on (ARCH_DAVINCI || ARCH_KEYSTONE) && OF
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index 27b493435e61..6d7e3e64ba62 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_ARCH_BRCMSTB) += brcmstb_dpfe.o
+obj-$(CONFIG_BT1_L2_CTL) += bt1-l2-ctl.o
obj-$(CONFIG_TI_AEMIF) += ti-aemif.o
obj-$(CONFIG_TI_EMIF) += emif.o
obj-$(CONFIG_OMAP_GPMC) += omap-gpmc.o
diff --git a/drivers/memory/bt1-l2-ctl.c b/drivers/memory/bt1-l2-ctl.c
new file mode 100644
index 000000000000..633fea6a4edf
--- /dev/null
+++ b/drivers/memory/bt1-l2-ctl.c
@@ -0,0 +1,322 @@
+// 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 scnprintf(buf, PAGE_SIZE, "%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");
+MODULE_LICENSE("GPL v2");