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authorArnd Bergmann <arnd@arndb.de>2020-05-28 14:18:11 +0200
committerArnd Bergmann <arnd@arndb.de>2020-05-28 14:18:11 +0200
commit0d583273b49a2305d6f5fff668575bdbf9e85c70 (patch)
tree98dc04b0c6bfeb818f8f196e4b05172d77380777 /drivers/memory
parent9536a3155bf098db6252198a278221c81029cfc9 (diff)
parent83ca8b3e8f213f49cc68b5c1fbcf88ebb24671eb (diff)
downloadlinux-0d583273b49a2305d6f5fff668575bdbf9e85c70.tar.bz2
Merge branch 'baikal/drivers' into arm/drivers
[arnd: This is a patch series from Serge Semin to add a few drivers that don't have any other subsystem maintainer tree to go through, so I'm picking them up through the soc tree, full series description from the mailing list below] Baikal-T1 SoC CPU is based on two MIPS Warrior P5600 cores. Their main memory Non-Coherent IO interface is connected to the OCP2AXI bridge, which in turn is then connected to the DW AMBA 3 AXI Interconnect (so called Main Interconnect) with nine masters and four slaves ports. Main Interconnect is responsible for the AXI-bus traffic arbitration (QoS) and its routing from one component to another. In addition there is a Errors Handler Block (EHB) accesible by means of the Baikal-T1 SoC System Controller responsible to detect AXI protocol errors and device not responding situations built on top the interconnect. Baikal-T1 AXI-bus driver included in this patchset will be responsible for working with that functionality, though currently it doesn't support QoS tuning. Instead it's capable of detecting the error events, reporting an info about them to the system log, injecting artificial errors to test the driver functionality. Since AXI Interconnect doesn't provide a way to find out which devices are connected to it, so its DT node is supposed to be compatible with "simple-bus" driver, while sub-nodes shall represent the masters attached to the bus. One of the AXI Interconnect slaves is an AXI-APB bridge used to access the Baikal-T1 SoC subsystems CSRs. MMIO request from CPU and DMAC masters are routed there if they are detected to be within [0x08000000 0x1FFFFFFF] range of the physical memory. In case if an attempted APB transaction stays with no response for a pre-defined time it will be detected by the APB-bus Errors Handler Block (EHB), which will raise an interrupt, then the bus gets freed for a next operation. The APB-bus driver provides the interrupt handler to detect the erroneous address, update an errors counter and prints an error message about the faulty address. The counter and the APB-bus operations timeout can be accessed via corresponding sysfs nodes. A dedicated sysfs-node can be also used to artificially cause the bus errors described above. Since APB-bus is a platform bus, it doesn't provide a way to detect slave devices connected to it, so similarly to the AXI-bus it's also supposed to be compatible with "simple-bus" driver. Aside from PCIe/SATA/DDR/I2C/EHB/CPU/reboot specific settings the Baikal-T1 System Controller provides a MIPS P5600 CM2 L2-cache tuning block. It is responsible for the setting up the Tag/Data/WS L2-to-RAM latencies. The last small patch in this patchset provides a driver and DT-schema-based binding for the described device. So that the latencies can be tuned up by means of dedicated DT properties and sysfs nodes. This patchset is rebased and tested on the mainline Linux kernel 5.7-rc4. Changelog v2 (AXI/APB bus): - Assign dual GPL/BSD licenses to the bindings. - Use single lined copyright headers in the bindings. - Replace "additionalProperties: false" property with "unevaluatedProperties: false" in the bindings. - Don't use a multi-arg clock phandle reference in DT binding examples. Thus remove includes from there. - Fix some commit message and Kconfig help text spelling. - Move drivers from soc to the bus subsystem. - Convert a simple EHB drivers to the Baikal-T1 AXI and APB bus ones. - Convert APB bus driver to using regmap MMIO API. - Use syscon regmap to access the AXI-bus erroneous address. - Add reset line support. - Add Main Interconnect clock support to the AXI-bus driver. - Remove probe-status info string printout. - Discard of_match_ptr() macro utilization. - Don't print error-message if no platform IRQ found. Just return an error. - Use generic FIELD_{GET,PREP} macros instead of handwritten ones in the AXI-bus driver. Changelog v2 (l2 driver): - Fix some commit message and Kconfig help text spelling. - Move the driver to the memory subsystem. - Assign dual GPL/BSD license to the DT binding. - Use single lined copyright header in the binding. - Discard reg property and syscon compatible string. - Move "allOf" restrictions to the root level of the properties. - The DT node is supposed to be a child of the Baikal-T1 system controller node. So regmap will be fetched from there. - Use generic FIELD_{GET,PREP} macro. - Remove probe-status info string printout. - Since the driver depends on the OF config we can remove of_match_ptr() macro utilization. Changelog v3: - Combine l2 and AXI/APB bus patches in a single patchset. - Retrieve AXI-bus QoS registers by resource name "qos". - Discard CONFIG_OF dependency since there is none at compile-time. - Add syscon EHB registers range to the AXI-bus reg property as optional entry. - Fix invalid of_property_read_u32() return value test in the l2-ctl driver. - Get the reg property back into the l2-ctl DT bindings even though the driver is using the parental syscon regmap. - The l2-ctl DT schema will live separately from the system controller, but the corresponding sub-node of the later DT schema will $ref this one. - Set non-default latencies in the l2-ctl DT example. * baikal/drivers: memory: Add Baikal-T1 L2-cache Control Block driver bus: Add Baikal-T1 APB-bus driver bus: Add Baikal-T1 AXI-bus driver dt-bindings: bus: Add Baikal-T1 APB-bus binding dt-bindings: bus: Add Baikal-T1 AXI-bus binding Link: https://lore.kernel.org/lkml/20200526130841.ap6qlxv7hqmabnh5@mobilestation/ Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/memory')
-rw-r--r--drivers/memory/Kconfig11
-rw-r--r--drivers/memory/Makefile1
-rw-r--r--drivers/memory/bt1-l2-ctl.c322
3 files changed, 334 insertions, 0 deletions
diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index 9bddca292330..04368ee2a809 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -46,6 +46,17 @@ config ATMEL_EBI
tree is used. This bus supports NANDs, external ethernet controller,
SRAMs, ATA devices, etc.
+config BT1_L2_CTL
+ bool "Baikal-T1 CM2 L2-RAM Cache Control Block"
+ depends on MIPS_BAIKAL_T1 || COMPILE_TEST
+ select MFD_SYSCON
+ help
+ Baikal-T1 CPU is based on the MIPS P5600 Warrior IP-core. The CPU
+ resides Coherency Manager v2 with embedded 1MB L2-cache. It's
+ possible to tune the L2 cache performance up by setting the data,
+ tags and way-select latencies of RAM access. This driver provides a
+ dt properties-based and sysfs interface for it.
+
config TI_AEMIF
tristate "Texas Instruments AEMIF driver"
depends on (ARCH_DAVINCI || ARCH_KEYSTONE) && OF
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index 27b493435e61..6d7e3e64ba62 100644
--- a/drivers/memory/Makefile
+++ b/drivers/memory/Makefile
@@ -11,6 +11,7 @@ obj-$(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");