diff options
Diffstat (limited to 'drivers/soc/loongson/loongson2_guts.c')
| -rw-r--r-- | drivers/soc/loongson/loongson2_guts.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/soc/loongson/loongson2_guts.c b/drivers/soc/loongson/loongson2_guts.c new file mode 100644 index 000000000000..bace4bc8e03b --- /dev/null +++ b/drivers/soc/loongson/loongson2_guts.c @@ -0,0 +1,192 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Author: Yinbo Zhu <[email protected]> + * Copyright (C) 2022-2023 Loongson Technology Corporation Limited + */ + +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/of_fdt.h> +#include <linux/sys_soc.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> + +static struct soc_device_attribute soc_dev_attr; +static struct soc_device *soc_dev; + +/* + * Global Utility Registers. + * + * Not all registers defined in this structure are available on all chips, so + * you are expected to know whether a given register actually exists on your + * chip before you access it. + * + * Also, some registers are similar on different chips but have slightly + * different names. In these cases, one name is chosen to avoid extraneous + * #ifdefs. + */ +struct scfg_guts { + u32 svr; /* Version Register */ + u8 res0[4]; + u16 feature; /* Feature Register */ + u32 vendor; /* Vendor Register */ + u8 res1[6]; + u32 id; + u8 res2[0x3ff8 - 0x18]; + u32 chip; +}; + +static struct guts { + struct scfg_guts __iomem *regs; + bool little_endian; +} *guts; + +struct loongson2_soc_die_attr { + char *die; + u32 svr; + u32 mask; +}; + +/* SoC die attribute definition for Loongson-2 platform */ +static const struct loongson2_soc_die_attr loongson2_soc_die[] = { + + /* + * LoongArch-based SoCs Loongson-2 Series + */ + + /* Die: 2k1000, SoC: 2k1000 */ + { .die = "2K1000", + .svr = 0x00000013, + .mask = 0x000000ff, + }, + { }, +}; + +static const struct loongson2_soc_die_attr *loongson2_soc_die_match( + u32 svr, const struct loongson2_soc_die_attr *matches) +{ + while (matches->svr) { + if (matches->svr == (svr & matches->mask)) + return matches; + matches++; + }; + + return NULL; +} + +static u32 loongson2_guts_get_svr(void) +{ + u32 svr = 0; + + if (!guts || !guts->regs) + return svr; + + if (guts->little_endian) + svr = ioread32(&guts->regs->svr); + else + svr = ioread32be(&guts->regs->svr); + + return svr; +} + +static int loongson2_guts_probe(struct platform_device *pdev) +{ + struct device_node *root, *np = pdev->dev.of_node; + struct device *dev = &pdev->dev; + struct resource *res; + const struct loongson2_soc_die_attr *soc_die; + const char *machine; + u32 svr; + + /* Initialize guts */ + guts = devm_kzalloc(dev, sizeof(*guts), GFP_KERNEL); + if (!guts) + return -ENOMEM; + + guts->little_endian = of_property_read_bool(np, "little-endian"); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + guts->regs = ioremap(res->start, res->end - res->start + 1); + if (IS_ERR(guts->regs)) + return PTR_ERR(guts->regs); + + /* Register soc device */ + root = of_find_node_by_path("/"); + if (of_property_read_string(root, "model", &machine)) + of_property_read_string_index(root, "compatible", 0, &machine); + of_node_put(root); + if (machine) + soc_dev_attr.machine = devm_kstrdup(dev, machine, GFP_KERNEL); + + svr = loongson2_guts_get_svr(); + soc_die = loongson2_soc_die_match(svr, loongson2_soc_die); + if (soc_die) { + soc_dev_attr.family = devm_kasprintf(dev, GFP_KERNEL, + "Loongson %s", soc_die->die); + } else { + soc_dev_attr.family = devm_kasprintf(dev, GFP_KERNEL, "Loongson"); + } + if (!soc_dev_attr.family) + return -ENOMEM; + soc_dev_attr.soc_id = devm_kasprintf(dev, GFP_KERNEL, + "svr:0x%08x", svr); + if (!soc_dev_attr.soc_id) + return -ENOMEM; + soc_dev_attr.revision = devm_kasprintf(dev, GFP_KERNEL, "%d.%d", + (svr >> 4) & 0xf, svr & 0xf); + if (!soc_dev_attr.revision) + return -ENOMEM; + + soc_dev = soc_device_register(&soc_dev_attr); + if (IS_ERR(soc_dev)) + return PTR_ERR(soc_dev); + + pr_info("Machine: %s\n", soc_dev_attr.machine); + pr_info("SoC family: %s\n", soc_dev_attr.family); + pr_info("SoC ID: %s, Revision: %s\n", + soc_dev_attr.soc_id, soc_dev_attr.revision); + + return 0; +} + +static int loongson2_guts_remove(struct platform_device *dev) +{ + soc_device_unregister(soc_dev); + + return 0; +} + +/* + * Table for matching compatible strings, for device tree + * guts node, for Loongson-2 SoCs. + */ +static const struct of_device_id loongson2_guts_of_match[] = { + { .compatible = "loongson,ls2k-chipid", }, + {} +}; +MODULE_DEVICE_TABLE(of, loongson2_guts_of_match); + +static struct platform_driver loongson2_guts_driver = { + .driver = { + .name = "loongson2-guts", + .of_match_table = loongson2_guts_of_match, + }, + .probe = loongson2_guts_probe, + .remove = loongson2_guts_remove, +}; + +static int __init loongson2_guts_init(void) +{ + return platform_driver_register(&loongson2_guts_driver); +} +core_initcall(loongson2_guts_init); + +static void __exit loongson2_guts_exit(void) +{ + platform_driver_unregister(&loongson2_guts_driver); +} +module_exit(loongson2_guts_exit); + +MODULE_DESCRIPTION("Loongson2 GUTS driver"); +MODULE_LICENSE("GPL"); |