From: Alexey Charkov Date: Sat, 3 May 2025 11:52:32 +0000 (+0400) Subject: soc: Add VIA/WonderMedia SoC identification driver X-Git-Tag: v6.16-rc1~100^2~10^2~2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=96f94587d7413401630569f288477e6d97028efd;p=thirdparty%2Flinux.git soc: Add VIA/WonderMedia SoC identification driver Add a small SOC bus driver to parse the chip ID and revision made available on VIA/WonderMedia SoCs via their system configuration controller's SCC_ID register. This is intended to select appropriate sets of on-chip device quirks at runtime, as it has been found that even within the same SoC version there can be register-incompatible differences, such as with the SDMMC controller on WM8505 rev. A0-A1 vs. rev. A2. The list of SoC versions is compiled from various vendor source dumps and not all of them have corresponding mainline driver support. Some of them also have been seen with varying on-chip markings while sharing the same hardware chip ID's (as is the case with e.g. WM8850 vs. WM8950). In such cases the selection of names to use here among those seen in various source dumps and chip markings was arbitrary. Suggested by Krzysztof at [1] - thanks a lot! [1] https://lore.kernel.org/all/14de236b-e2a7-4bde-986d-1e5ffddd01b4@kernel.org/ Signed-off-by: Alexey Charkov Link: https://lore.kernel.org/r/20250503-wmt-soc-driver-v3-2-2daa9056fa10@gmail.com Signed-off-by: Krzysztof Kozlowski --- diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig index 6a8daeb8c4b96..37ca3f094f899 100644 --- a/drivers/soc/Kconfig +++ b/drivers/soc/Kconfig @@ -28,6 +28,7 @@ source "drivers/soc/tegra/Kconfig" source "drivers/soc/ti/Kconfig" source "drivers/soc/ux500/Kconfig" source "drivers/soc/versatile/Kconfig" +source "drivers/soc/vt8500/Kconfig" source "drivers/soc/xilinx/Kconfig" endmenu diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile index 2037a8695cb28..777255401252e 100644 --- a/drivers/soc/Makefile +++ b/drivers/soc/Makefile @@ -34,4 +34,5 @@ obj-$(CONFIG_ARCH_TEGRA) += tegra/ obj-y += ti/ obj-$(CONFIG_ARCH_U8500) += ux500/ obj-y += versatile/ +obj-y += vt8500/ obj-y += xilinx/ diff --git a/drivers/soc/vt8500/Kconfig b/drivers/soc/vt8500/Kconfig new file mode 100644 index 0000000000000..b4cc0ba1128b4 --- /dev/null +++ b/drivers/soc/vt8500/Kconfig @@ -0,0 +1,19 @@ +# SPDX-License-Identifier: GPL-2.0-only + +if ARCH_VT8500 || COMPILE_TEST + +menu "VIA/WonderMedia SoC drivers" + +config WMT_SOCINFO + bool "VIA/WonderMedia SoC Information driver" + default ARCH_VT8500 + select SOC_BUS + help + Say yes to support decoding of VIA/WonderMedia system configuration + register information. This currently includes just the chip ID register + which helps identify the exact hardware revision of the SoC the kernel + is running on (to know if any revision-specific quirks are required) + +endmenu + +endif diff --git a/drivers/soc/vt8500/Makefile b/drivers/soc/vt8500/Makefile new file mode 100644 index 0000000000000..05964c5f28909 --- /dev/null +++ b/drivers/soc/vt8500/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +obj-$(CONFIG_WMT_SOCINFO) += wmt-socinfo.o diff --git a/drivers/soc/vt8500/wmt-socinfo.c b/drivers/soc/vt8500/wmt-socinfo.c new file mode 100644 index 0000000000000..461f8c1ae56ee --- /dev/null +++ b/drivers/soc/vt8500/wmt-socinfo.c @@ -0,0 +1,125 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2025 Alexey Charkov + * Based on aspeed-socinfo.c + */ + +#include +#include +#include +#include +#include +#include + +static const struct { + const char *name; + const u32 id; +} chip_id_table[] = { + /* VIA */ + { "VT8420", 0x3300 }, + { "VT8430", 0x3357 }, + { "VT8500", 0x3400 }, + + /* WonderMedia */ + { "WM8425", 0x3429 }, + { "WM8435", 0x3437 }, + { "WM8440", 0x3451 }, + { "WM8505", 0x3426 }, + { "WM8650", 0x3465 }, + { "WM8750", 0x3445 }, + { "WM8850", 0x3481 }, + { "WM8880", 0x3498 }, +}; + +static const char *sccid_to_name(u32 sccid) +{ + u32 id = sccid >> 16; + unsigned int i; + + for (i = 0 ; i < ARRAY_SIZE(chip_id_table) ; ++i) { + if (chip_id_table[i].id == id) + return chip_id_table[i].name; + } + + return "Unknown"; +} + +static int wmt_socinfo_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct soc_device_attribute *attrs; + struct soc_device *soc_dev; + char letter, digit; + void __iomem *reg; + u32 sccid; + + reg = devm_of_iomap(&pdev->dev, np, 0, NULL); + if (IS_ERR(reg)) + return PTR_ERR(reg); + + sccid = readl(reg); + + attrs = devm_kzalloc(&pdev->dev, sizeof(*attrs), GFP_KERNEL); + if (!attrs) + return -ENOMEM; + + /* + * Machine: VIA APC Rock + * Family: WM8850 + * Revision: A2 + * SoC ID: raw silicon revision id (34810103 in hexadecimal) + */ + + attrs->family = sccid_to_name(sccid); + + letter = (sccid >> 8) & 0xf; + letter = (letter - 1) + 'A'; + digit = sccid & 0xff; + digit = (digit - 1) + '0'; + attrs->revision = devm_kasprintf(&pdev->dev, GFP_KERNEL, + "%c%c", letter, digit); + + attrs->soc_id = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%08x", sccid); + + if (!attrs->revision || !attrs->soc_id) + return -ENOMEM; + + soc_dev = soc_device_register(attrs); + if (IS_ERR(soc_dev)) + return PTR_ERR(soc_dev); + + dev_info(&pdev->dev, + "VIA/WonderMedia %s rev %s (%s)\n", + attrs->family, + attrs->revision, + attrs->soc_id); + + platform_set_drvdata(pdev, soc_dev); + return 0; +} + +static void wmt_socinfo_remove(struct platform_device *pdev) +{ + struct soc_device *soc_dev = platform_get_drvdata(pdev); + + soc_device_unregister(soc_dev); +} + +static const struct of_device_id wmt_socinfo_ids[] = { + { .compatible = "via,vt8500-scc-id" }, + { /* Sentinel */ }, +}; + +static struct platform_driver wmt_socinfo = { + .probe = wmt_socinfo_probe, + .remove = wmt_socinfo_remove, + .driver = { + .name = "wmt-socinfo", + .of_match_table = wmt_socinfo_ids, + }, +}; +module_platform_driver(wmt_socinfo); + +MODULE_AUTHOR("Alexey Charkov "); +MODULE_DESCRIPTION("VIA/WonderMedia socinfo driver"); +MODULE_LICENSE("GPL");