// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2017 Linaro Ltd. * * Author: Linus Walleij <linus.walleij@linaro.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2, as * published by the Free Software Foundation. * */ #include <linux/init.h> #include <linux/kernel.h> #include <linux/mfd/syscon.h> #include <linux/regmap.h> #include <linux/of.h> #define GLOBAL_WORD_ID 0x00 #define GEMINI_GLOBAL_ARB1_CTRL 0x2c #define GEMINI_ARB1_BURST_MASK GENMASK(21, 16) #define GEMINI_ARB1_BURST_SHIFT 16 /* These all define the priority on the BUS2 backplane */ #define GEMINI_ARB1_PRIO_MASK GENMASK(9, 0) #define GEMINI_ARB1_DMAC_HIGH_PRIO BIT(0) #define GEMINI_ARB1_IDE_HIGH_PRIO BIT(1) #define GEMINI_ARB1_RAID_HIGH_PRIO BIT(2) #define GEMINI_ARB1_SECURITY_HIGH_PRIO BIT(3) #define GEMINI_ARB1_GMAC0_HIGH_PRIO BIT(4) #define GEMINI_ARB1_GMAC1_HIGH_PRIO BIT(5) #define GEMINI_ARB1_USB0_HIGH_PRIO BIT(6) #define GEMINI_ARB1_USB1_HIGH_PRIO BIT(7) #define GEMINI_ARB1_PCI_HIGH_PRIO BIT(8) #define GEMINI_ARB1_TVE_HIGH_PRIO BIT(9) #define GEMINI_DEFAULT_BURST_SIZE 0x20 #define GEMINI_DEFAULT_PRIO (GEMINI_ARB1_GMAC0_HIGH_PRIO | \ GEMINI_ARB1_GMAC1_HIGH_PRIO) static int __init gemini_soc_init(void) { struct regmap *map; u32 rev; u32 val; int ret; /* Multiplatform guard, only proceed on Gemini */ if (!of_machine_is_compatible("cortina,gemini")) return 0; map = syscon_regmap_lookup_by_compatible("cortina,gemini-syscon"); if (IS_ERR(map)) return PTR_ERR(map); ret = regmap_read(map, GLOBAL_WORD_ID, &rev); if (ret) return ret; val = (GEMINI_DEFAULT_BURST_SIZE << GEMINI_ARB1_BURST_SHIFT) | GEMINI_DEFAULT_PRIO; /* Set up system arbitration */ regmap_update_bits(map, GEMINI_GLOBAL_ARB1_CTRL, GEMINI_ARB1_BURST_MASK | GEMINI_ARB1_PRIO_MASK, val); pr_info("Gemini SoC %04x revision %02x, set arbitration %08x\n", rev >> 8, rev & 0xff, val); return 0; } subsys_initcall(gemini_soc_init); |