/* * This file is part of the coreboot project. * * Copyright (C) 2012 Alexandru Gagniuc * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include "vx900.h" #include "chip.h" #include #include #include #include #include #include #include #include #define RAM_4GB (((u64)1) << 32) static uint64_t uma_memory_base = 0; static uint64_t uma_memory_size = 0; /** * @file vx900/northbridge.c * * STATUS: Pretty good * One thing that needs to be thoroughly tested is the remap above 4G logic. * Unfortunately, while we cannot initialize odd ranks, our testing * possibilities are somewhat limited. A point of failure that is not covered is * when the amount of RAM and PCI config space added up exceeds 8GB. The * remapping mechanism will overflow, the effects of which are unknown. */ void do_board_reset(void) { system_reset(); } uint64_t get_uma_memory_base(void) { printk(BIOS_DEBUG, "UMA base 0x%.8llx (%lluMB)\n", uma_memory_base, uma_memory_base >> 20); printk(BIOS_DEBUG, "UMA size 0x%.8llx (%lluMB)\n", uma_memory_size, uma_memory_size >> 20); return uma_memory_base; } static u64 vx900_get_top_of_ram(struct device *mcu) { u16 reg16; /* The last valid DRAM address is computed by the MCU * One issue might be if we have a hole in the rank mappings, so that * virtual ranks are not mapped successively in the linear address space * (Ex: rank 0 mapped 0-1G, rank 1 mapped 2G-3G) * We don't do this awkward mapping in RAM init, so we don't worry about * it here, but it is something to keep in mind if having RAM issues */ reg16 = pci_read_config16(mcu, 0x88) & 0x07ff; return (u64) reg16 << 24; } /* * This guy is meant to go away, but for now, leave it in so that we can see * if the logic to remap RAM above 4G has errors. */ static void killme_debug_4g_remap_reg(u32 reg32) { if (reg32 & (1 << 0)) printk(BIOS_DEBUG, "Mem remapping enabled\n"); u64 remapstart = (reg32 >> 2) & 0x3ff; u64 remapend = (reg32 >> 14) & 0x3ff; remapstart <<= 26; remapend <<= 26; printk(BIOS_DEBUG, "Remapstart %lld(MB)\n", remapstart >> 20); printk(BIOS_DEBUG, "Remapend %lld(MB)\n", remapend >> 20); } /** * \brief Remap low memory colliding with PCI MMIO space, above 4G * * @param mcu The memory controller * @param tolm Top of low memory. * * @return The new top of memory. */ static u64 vx900_remap_above_4g(struct device *mcu, u32 tolm) { size_t i; u8 reg8, start8, end8, start, end; u16 reg16; u32 reg32; u64 tor, newtor, chunk; /* * The remapping mechanism works like this: * * - Choose the top of low memory. * This becomes the "remap from" * - Choose a chunk above 4G where to remap. * This becomes "remap to" * - Choose a chunk above 4G where to end the remapping. * This becomes "remap until" * * This remaps a "chunk" of memory where we want to. * sizeof(chunk) = until - to; * * Therefore the memory region from "from" to " from + sizeof(chunk)" * becomes accessible at "to" to "until" */ if (tolm >= vx900_get_top_of_ram(mcu)) { printk(BIOS_DEBUG, "Nothing to remap\n"); return 0; } /* This is how the Vendor BIOS. Keep it for comparison for now */ killme_debug_4g_remap_reg(0x00180141); /* We can remap with a granularity of 64MB, so align tolm */ tolm &= ~((64 * MiB) - 1); /* The "start remapping from where ?" register */ reg16 = ((tolm >> 20) & 0xfff) << 4; pci_update_config16(mcu, 0x84, (u16)~0xfff0, reg16); /* Find the chunk size */ tor = vx900_get_top_of_ram(mcu); printk(BIOS_DEBUG, "Top of RAM %lldMB\n", tor >> 20); if (tor < RAM_4GB) { chunk = tor - tolm; newtor = RAM_4GB + chunk; } else { chunk = (RAM_4GB - tolm); newtor = tor + chunk; } printk(BIOS_DEBUG, "New top of RAM %lldMB\n", newtor >> 20); reg8 = tolm >> 26; /* Which rank does the PCI TOLM fall on? */ for (i = 0; i < VX900_MAX_MEM_RANKS; i++) { end8 = pci_read_config8(mcu, 0x40 + i); if (reg8 > end8) continue; start8 = pci_read_config8(mcu, 0x48 + i); if (reg8 <= start8) continue; printk(BIOS_DEBUG, "Address %x falls on rank %zu\n", tolm, i); break; } for (; i < VX900_MAX_MEM_RANKS; i++) { start = pci_read_config8(mcu, 0x48 + i); end = pci_read_config8(mcu, 0x40 + i); if (end == 0) { printk(BIOS_DEBUG, "Huh? rank %zu empty?\n", i); continue; } if (end < (tolm >> 26)) { printk(BIOS_DEBUG, "Huh? rank %zu don't need remap?\n", i); continue; } printk(BIOS_DEBUG, "Physical rank %u is mapped to\n" " Start address: 0x%.10llx (%dMB)\n" " End address: 0x%.10llx (%dMB)\n", (int)i, ((u64) start << 26), (start << (26 - 20)), ((u64) end << 26), (end << (26 - 20))); if (end < (RAM_4GB >> 26)) end = (RAM_4GB >> 26); if (end >= (tolm >> 26)) end += chunk >> 26; if (start > (tolm >> 26)) start += chunk >> 26; pci_write_config8(mcu, 0x48 + i, start); pci_write_config8(mcu, 0x40 + i, end); printk(BIOS_DEBUG, "ReMapped Physical rank %u, to\n" " Start address: 0x%.10llx (%dMB)\n" " End address: 0x%.10llx (%dMB)\n", (int)i, ((u64) start << 26), (start << (26 - 20)), ((u64) end << 26), (end << (26 - 20))); } /* The "remap to where?" register */ reg32 = ((MAX(tor, RAM_4GB) >> 26) & 0x3ff) << 2; /* The "remap until where?" register */ reg32 |= ((newtor >> 26) & 0x3ff) << 14; /* Now enable the goodies */ reg32 |= (1 << 0); pci_write_config32(mcu, 0xf8, reg32); printk(BIOS_DEBUG, "Wrote remap map %x\n", reg32); killme_debug_4g_remap_reg(reg32); printk(BIOS_DEBUG, "New top of memory is at %lldMB\n", newtor >> 20); return newtor; } static void vx900_set_resources(struct device *dev) { u32 pci_tolm, tomk, vx900_tolm, full_tolmk, fbufk, tolmk; printk(BIOS_DEBUG, "========================================" "========================================\n"); printk(BIOS_DEBUG, "============= VX900 memory sizing & Co. " "========================================\n"); printk(BIOS_DEBUG, "========================================" "========================================\n"); int idx = 10; struct device *const mcu = dev_find_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX900_MEMCTRL, 0); if (!mcu) { die("Something is terribly wrong.\n" " We tried locating the MCU on the PCI bus, " "but couldn't find it. Halting.\n"); } /* How much low adrress space do we have? */ pci_tolm = find_pci_tolm(dev->link_list); printk(BIOS_SPEW, "Found PCI tolm at %.8x\n", pci_tolm); printk(BIOS_SPEW, "Found PCI tolm at %dMB\n", pci_tolm >> 20); /* Figure out the total amount of RAM */ tomk = vx900_get_top_of_ram(mcu) >> 10; printk(BIOS_SPEW, "Found top of memory at %dMB\n", tomk >> 10); /* Do the same for top of low RAM */ vx900_tolm = vx900_get_tolm(); full_tolmk = vx900_tolm << (20 - 10); /* Remap above 4G if needed */ full_tolmk = MIN(full_tolmk, pci_tolm >> 10); printk(BIOS_SPEW, "Found top of low memory at %dMB\n", full_tolmk >> 10); /* What about the framebuffer for the integrated GPU? */ fbufk = vx900_get_chrome9hd_fb_size() << (20 - 10); printk(BIOS_SPEW, "Integrated graphics buffer: %dMB\n", fbufk >> 10); /* Can't use the framebuffer as system RAM, sorry */ tolmk = MIN(full_tolmk, tomk); tolmk -= fbufk; ram_resource(dev, idx++, 0, 640); printk(BIOS_SPEW, "System RAM left: %dMB\n", tolmk >> 10); /* FIXME: how can we avoid leaving this hole? * Leave a hole for VGA, 0xa0000 - 0xc0000 ?? */ /* TODO: VGA Memory hole can be disabled in SNMIC. Upper 64k of ROM seem * to be always mapped to the top of 1M, but this can be overcome with * some smart positive/subtractive resource decoding */ ram_resource(dev, idx++, 768, (tolmk - 768)); uma_memory_size = fbufk << 10; uma_memory_base = tolmk << 10; //uma_resource(dev, idx++, uma_memory_base>>10, uma_memory_size>>10); printk(BIOS_DEBUG, "UMA @ %lldMB + %lldMB\n", uma_memory_base >> 20, uma_memory_size >> 20); /* FIXME: How do we handle remapping above 4G? */ u64 tor = vx900_remap_above_4g(mcu, pci_tolm); if (tor) ram_resource(dev, idx++, RAM_4GB >> 10, (tor - RAM_4GB) >> 10); printk(BIOS_DEBUG, "======================================================\n"); assign_resources(dev->link_list); } static void vx900_read_resources(struct device *dev) { /* Our fixed resources start at 0 */ int idx = 0; /* Reserve our ROM mapped space */ struct resource *res; res = new_resource(dev, idx++); res->size = CONFIG_ROM_SIZE; res->base = 0xffffffff - (res->size - 1); res->flags = IORESOURCE_MEM | IORESOURCE_ASSIGNED | IORESOURCE_FIXED; /* Now do the same for our MMCONF * We always run with MMCONF enabled. We need to access the extended * config space when configuring PCI-Express links */ mmconf_resource(dev, idx++); pci_domain_read_resources(dev); } static struct device_operations pci_domain_ops = { .read_resources = vx900_read_resources, .set_resources = vx900_set_resources, .enable_resources = NULL, .init = NULL, .scan_bus = pci_domain_scan_bus, }; static void cpu_bus_init(struct device *dev) { initialize_cpus(dev->link_list); } static struct device_operations cpu_bus_ops = { .read_resources = DEVICE_NOOP, .set_resources = DEVICE_NOOP, .enable_resources = DEVICE_NOOP, .init = cpu_bus_init, .scan_bus = 0, }; static void enable_dev(struct device *dev) { /* Set the operations if it is a special bus type */ if (dev->path.type == DEVICE_PATH_DOMAIN) { dev->ops = &pci_domain_ops; } else if (dev->path.type == DEVICE_PATH_CPU_CLUSTER) { dev->ops = &cpu_bus_ops; } } struct chip_operations northbridge_via_vx900_ops = { CHIP_NAME("VIA VX900 Chipset") .enable_dev = enable_dev, };