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path: root/drivers/mfd/altera-sysmgr.c
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Diffstat (limited to 'drivers/mfd/altera-sysmgr.c')
-rw-r--r--drivers/mfd/altera-sysmgr.c199
1 files changed, 199 insertions, 0 deletions
diff --git a/drivers/mfd/altera-sysmgr.c b/drivers/mfd/altera-sysmgr.c
new file mode 100644
index 0000000000..0e52bd2ebd
--- /dev/null
+++ b/drivers/mfd/altera-sysmgr.c
@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018-2019, Intel Corporation.
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ * Copyright (C) 2012 Linaro Ltd.
+ *
+ * Based on syscon driver.
+ */
+
+#include <linux/arm-smccc.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/mfd/altera-sysmgr.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+/**
+ * struct altr_sysmgr - Altera SOCFPGA System Manager
+ * @regmap: the regmap used for System Manager accesses.
+ */
+struct altr_sysmgr {
+ struct regmap *regmap;
+};
+
+static struct platform_driver altr_sysmgr_driver;
+
+/**
+ * s10_protected_reg_write
+ * Write to a protected SMC register.
+ * @base: Base address of System Manager
+ * @reg: Address offset of register
+ * @val: Value to write
+ * Return: INTEL_SIP_SMC_STATUS_OK (0) on success
+ * INTEL_SIP_SMC_REG_ERROR on error
+ * INTEL_SIP_SMC_RETURN_UNKNOWN_FUNCTION if not supported
+ */
+static int s10_protected_reg_write(void *base,
+ unsigned int reg, unsigned int val)
+{
+ struct arm_smccc_res result;
+ unsigned long sysmgr_base = (unsigned long)base;
+
+ arm_smccc_smc(INTEL_SIP_SMC_REG_WRITE, sysmgr_base + reg,
+ val, 0, 0, 0, 0, 0, &result);
+
+ return (int)result.a0;
+}
+
+/**
+ * s10_protected_reg_read
+ * Read the status of a protected SMC register
+ * @base: Base address of System Manager.
+ * @reg: Address of register
+ * @val: Value read.
+ * Return: INTEL_SIP_SMC_STATUS_OK (0) on success
+ * INTEL_SIP_SMC_REG_ERROR on error
+ * INTEL_SIP_SMC_RETURN_UNKNOWN_FUNCTION if not supported
+ */
+static int s10_protected_reg_read(void *base,
+ unsigned int reg, unsigned int *val)
+{
+ struct arm_smccc_res result;
+ unsigned long sysmgr_base = (unsigned long)base;
+
+ arm_smccc_smc(INTEL_SIP_SMC_REG_READ, sysmgr_base + reg,
+ 0, 0, 0, 0, 0, 0, &result);
+
+ *val = (unsigned int)result.a1;
+
+ return (int)result.a0;
+}
+
+static struct regmap_config altr_sysmgr_regmap_cfg = {
+ .name = "altr_sysmgr",
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .fast_io = true,
+ .use_single_read = true,
+ .use_single_write = true,
+};
+
+/**
+ * altr_sysmgr_regmap_lookup_by_phandle
+ * Find the sysmgr previous configured in probe() and return regmap property.
+ * Return: regmap if found or error if not found.
+ *
+ * @np: Pointer to device's Device Tree node
+ * @property: Device Tree property name which references the sysmgr
+ */
+struct regmap *altr_sysmgr_regmap_lookup_by_phandle(struct device_node *np,
+ const char *property)
+{
+ struct device *dev;
+ struct altr_sysmgr *sysmgr;
+ struct device_node *sysmgr_np;
+
+ if (property)
+ sysmgr_np = of_parse_phandle(np, property, 0);
+ else
+ sysmgr_np = np;
+
+ if (!sysmgr_np)
+ return ERR_PTR(-ENODEV);
+
+ dev = driver_find_device_by_of_node(&altr_sysmgr_driver.driver,
+ (void *)sysmgr_np);
+ of_node_put(sysmgr_np);
+ if (!dev)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ sysmgr = dev_get_drvdata(dev);
+
+ return sysmgr->regmap;
+}
+EXPORT_SYMBOL_GPL(altr_sysmgr_regmap_lookup_by_phandle);
+
+static int sysmgr_probe(struct platform_device *pdev)
+{
+ struct altr_sysmgr *sysmgr;
+ struct regmap *regmap;
+ struct resource *res;
+ struct regmap_config sysmgr_config = altr_sysmgr_regmap_cfg;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ void __iomem *base;
+
+ sysmgr = devm_kzalloc(dev, sizeof(*sysmgr), GFP_KERNEL);
+ if (!sysmgr)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENOENT;
+
+ sysmgr_config.max_register = resource_size(res) -
+ sysmgr_config.reg_stride;
+ if (of_device_is_compatible(np, "altr,sys-mgr-s10")) {
+ sysmgr_config.reg_read = s10_protected_reg_read;
+ sysmgr_config.reg_write = s10_protected_reg_write;
+
+ /* Need physical address for SMCC call */
+ regmap = devm_regmap_init(dev, NULL,
+ (void *)(uintptr_t)res->start,
+ &sysmgr_config);
+ } else {
+ base = devm_ioremap(dev, res->start, resource_size(res));
+ if (!base)
+ return -ENOMEM;
+
+ sysmgr_config.max_register = resource_size(res) - 4;
+ regmap = devm_regmap_init_mmio(dev, base, &sysmgr_config);
+ }
+
+ if (IS_ERR(regmap)) {
+ pr_err("regmap init failed\n");
+ return PTR_ERR(regmap);
+ }
+
+ sysmgr->regmap = regmap;
+
+ platform_set_drvdata(pdev, sysmgr);
+
+ return 0;
+}
+
+static const struct of_device_id altr_sysmgr_of_match[] = {
+ { .compatible = "altr,sys-mgr" },
+ { .compatible = "altr,sys-mgr-s10" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, altr_sysmgr_of_match);
+
+static struct platform_driver altr_sysmgr_driver = {
+ .probe = sysmgr_probe,
+ .driver = {
+ .name = "altr,system_manager",
+ .of_match_table = altr_sysmgr_of_match,
+ },
+};
+
+static int __init altr_sysmgr_init(void)
+{
+ return platform_driver_register(&altr_sysmgr_driver);
+}
+core_initcall(altr_sysmgr_init);
+
+static void __exit altr_sysmgr_exit(void)
+{
+ platform_driver_unregister(&altr_sysmgr_driver);
+}
+module_exit(altr_sysmgr_exit);
+
+MODULE_AUTHOR("Thor Thayer <>");
+MODULE_DESCRIPTION("SOCFPGA System Manager driver");