mm.c

linux内核源码

/*
 *  PS3 address space management.
 *
 *  Copyright (C) 2006 Sony Computer Entertainment Inc.
 *  Copyright 2006 Sony Corp.
 *
 *  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; version 2 of the License.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/memory_hotplug.h>

#include <asm/firmware.h>
#include <asm/lmb.h>
#include <asm/udbg.h>
#include <asm/lv1call.h>

#include "platform.h"

#if defined(DEBUG)
#define DBG udbg_printf
#else
#define DBG pr_debug
#endif

enum {
#if defined(CONFIG_PS3_USE_LPAR_ADDR)
	USE_LPAR_ADDR = 1,
#else
	USE_LPAR_ADDR = 0,
#endif
#if defined(CONFIG_PS3_DYNAMIC_DMA)
	USE_DYNAMIC_DMA = 1,
#else
	USE_DYNAMIC_DMA = 0,
#endif
};

enum {
	PAGE_SHIFT_4K = 12U,
	PAGE_SHIFT_64K = 16U,
	PAGE_SHIFT_16M = 24U,
};

static unsigned long make_page_sizes(unsigned long a, unsigned long b)
{
	return (a << 56) | (b << 48);
}

enum {
	ALLOCATE_MEMORY_TRY_ALT_UNIT = 0X04,
	ALLOCATE_MEMORY_ADDR_ZERO = 0X08,
};

/* valid htab sizes are {18,19,20} = 256K, 512K, 1M */

enum {
	HTAB_SIZE_MAX = 20U, /* HV limit of 1MB */
	HTAB_SIZE_MIN = 18U, /* CPU limit of 256KB */
};

/*============================================================================*/
/* virtual address space routines                                             */
/*============================================================================*/

/**
 * struct mem_region - memory region structure
 * @base: base address
 * @size: size in bytes
 * @offset: difference between base and rm.size
 */

struct mem_region {
	unsigned long base;
	unsigned long size;
	unsigned long offset;
};

/**
 * struct map - address space state variables holder
 * @total: total memory available as reported by HV
 * @vas_id - HV virtual address space id
 * @htab_size: htab size in bytes
 *
 * The HV virtual address space (vas) allows for hotplug memory regions.
 * Memory regions can be created and destroyed in the vas at runtime.
 * @rm: real mode (bootmem) region
 * @r1: hotplug memory region(s)
 *
 * ps3 addresses
 * virt_addr: a cpu 'translated' effective address
 * phys_addr: an address in what Linux thinks is the physical address space
 * lpar_addr: an address in the HV virtual address space
 * bus_addr: an io controller 'translated' address on a device bus
 */

struct map {
	unsigned long total;
	unsigned long vas_id;
	unsigned long htab_size;
	struct mem_region rm;
	struct mem_region r1;
};

#define debug_dump_map(x) _debug_dump_map(x, __func__, __LINE__)
static void __maybe_unused _debug_dump_map(const struct map *m,
	const char *func, int line)
{
	DBG("%s:%d: map.total     = %lxh\n", func, line, m->total);
	DBG("%s:%d: map.rm.size   = %lxh\n", func, line, m->rm.size);
	DBG("%s:%d: map.vas_id    = %lu\n", func, line, m->vas_id);
	DBG("%s:%d: map.htab_size = %lxh\n", func, line, m->htab_size);
	DBG("%s:%d: map.r1.base   = %lxh\n", func, line, m->r1.base);
	DBG("%s:%d: map.r1.offset = %lxh\n", func, line, m->r1.offset);
	DBG("%s:%d: map.r1.size   = %lxh\n", func, line, m->r1.size);
}

static struct map map;

/**
 * ps3_mm_phys_to_lpar - translate a linux physical address to lpar address
 * @phys_addr: linux physical address
 */

unsigned long ps3_mm_phys_to_lpar(unsigned long phys_addr)
{
	BUG_ON(is_kernel_addr(phys_addr));
	if (USE_LPAR_ADDR)
		return phys_addr;
	else
		return (phys_addr < map.rm.size || phys_addr >= map.total)
			? phys_addr : phys_addr + map.r1.offset;
}

EXPORT_SYMBOL(ps3_mm_phys_to_lpar);

/**
 * ps3_mm_vas_create - create the virtual address space
 */

void __init ps3_mm_vas_create(unsigned long* htab_size)
{
	int result;
	unsigned long start_address;
	unsigned long size;
	unsigned long access_right;
	unsigned long max_page_size;
	unsigned long flags;

	result = lv1_query_logical_partition_address_region_info(0,
		&start_address, &size, &access_right, &max_page_size,
		&flags);

	if (result) {
		DBG("%s:%d: lv1_query_logical_partition_address_region_info "
			"failed: %s\n", __func__, __LINE__,
			ps3_result(result));
		goto fail;
	}

	if (max_page_size < PAGE_SHIFT_16M) {
		DBG("%s:%d: bad max_page_size %lxh\n", __func__, __LINE__,
			max_page_size);
		goto fail;
	}

	BUILD_BUG_ON(CONFIG_PS3_HTAB_SIZE > HTAB_SIZE_MAX);
	BUILD_BUG_ON(CONFIG_PS3_HTAB_SIZE < HTAB_SIZE_MIN);

	result = lv1_construct_virtual_address_space(CONFIG_PS3_HTAB_SIZE,
			2, make_page_sizes(PAGE_SHIFT_16M, PAGE_SHIFT_64K),
			&map.vas_id, &map.htab_size);

	if (result) {
		DBG("%s:%d: lv1_construct_virtual_address_space failed: %s\n",
			__func__, __LINE__, ps3_result(result));
		goto fail;
	}

	result = lv1_select_virtual_address_space(map.vas_id);

	if (result) {
		DBG("%s:%d: lv1_select_virtual_address_space failed: %s\n",
			__func__, __LINE__, ps3_result(result));
		goto fail;
	}

	*htab_size = map.htab_size;

	debug_dump_map(&map);

	return;

fail:
	panic("ps3_mm_vas_create failed");
}

/**
 * ps3_mm_vas_destroy -
 */

void ps3_mm_vas_destroy(void)
{
	int result;

	DBG("%s:%d: map.vas_id    = %lu\n", __func__, __LINE__, map.vas_id);

	if (map.vas_id) {
		result = lv1_select_virtual_address_space(0);
		BUG_ON(result);
		result = lv1_destruct_virtual_address_space(map.vas_id);
		BUG_ON(result);
		map.vas_id = 0;
	}
}

/*============================================================================*/
/* memory hotplug routines                                                    */
/*============================================================================*/

/**
 * ps3_mm_region_create - create a memory region in the vas
 * @r: pointer to a struct mem_region to accept initialized values
 * @size: requested region size
 *
 * This implementation creates the region with the vas large page size.
 * @size is rounded down to a multiple of the vas large page size.
 */

static int ps3_mm_region_create(struct mem_region *r, unsigned long size)
{
	int result;
	unsigned long muid;

	r->size = _ALIGN_DOWN(size, 1 << PAGE_SHIFT_16M);

	DBG("%s:%d requested  %lxh\n", __func__, __LINE__, size);
	DBG("%s:%d actual     %lxh\n", __func__, __LINE__, r->size);
	DBG("%s:%d difference %lxh (%luMB)\n", __func__, __LINE__,
		(unsigned long)(size - r->size),
		(size - r->size) / 1024 / 1024);

	if (r->size == 0) {
		DBG("%s:%d: size == 0\n", __func__, __LINE__);
		result = -1;
		goto zero_region;
	}

	result = lv1_allocate_memory(r->size, PAGE_SHIFT_16M, 0,
		ALLOCATE_MEMORY_TRY_ALT_UNIT, &r->base, &muid);

	if (result || r->base < map.rm.size) {
		DBG("%s:%d: lv1_allocate_memory failed: %s\n",
			__func__, __LINE__, ps3_result(result));
		goto zero_region;
	}

	r->offset = r->base - map.rm.size;
	return result;

zero_region:
	r->size = r->base = r->offset = 0;
	return result;
}

/**
 * ps3_mm_region_destroy - destroy a memory region
 * @r: pointer to struct mem_region
 */

static void ps3_mm_region_destroy(struct mem_region *r)
{
	int result;

	DBG("%s:%d: r->base = %lxh\n", __func__, __LINE__, r->base);
	if (r->base) {
		result = lv1_release_memory(r->base);
		BUG_ON(result);
		r->size = r->base = r->offset = 0;
		map.total = map.rm.size;
	}
}

/**
 * ps3_mm_add_memory - hot add memory
 */

static int __init ps3_mm_add_memory(void)
{
	int result;
	unsigned long start_addr;
	unsigned long start_pfn;
	unsigned long nr_pages;

	if (!firmware_has_feature(FW_FEATURE_PS3_LV1))
		return -ENODEV;

	BUG_ON(!mem_init_done);

	start_addr = USE_LPAR_ADDR ? map.r1.base : map.rm.size;
	start_pfn = start_addr >> PAGE_SHIFT;
	nr_pages = (map.r1.size + PAGE_SIZE - 1) >> PAGE_SHIFT;

	DBG("%s:%d: start_addr %lxh, start_pfn %lxh, nr_pages %lxh\n",
		__func__, __LINE__, start_addr, start_pfn, nr_pages);

	result = add_memory(0, start_addr, map.r1.size);

	if (result) {
		DBG("%s:%d: add_memory failed: (%d)\n",
			__func__, __LINE__, result);
		return result;
	}

	result = online_pages(start_pfn, nr_pages);

	if (result)
		DBG("%s:%d: online_pages failed: (%d)\n",
			__func__, __LINE__, result);

	return result;
}

core_initcall(ps3_mm_add_memory);

/*============================================================================*/
/* dma routines                                                               */
/*============================================================================*/

/**
 * dma_sb_lpar_to_bus - Translate an lpar address to ioc mapped bus address.
 * @r: pointer to dma region structure
 * @lpar_addr: HV lpar address
 */

static unsigned long dma_sb_lpar_to_bus(struct ps3_dma_region *r,
	unsigned long lpar_addr)
{
	if (lpar_addr >= map.rm.size)
		lpar_addr -= map.r1.offset;
	BUG_ON(lpar_addr < r->offset);
	BUG_ON(lpar_addr >= r->offset + r->len);
	return r->bus_addr + lpar_addr - r->offset;
}

#define dma_dump_region(_a) _dma_dump_region(_a, __func__, __LINE__)
static void  __maybe_unused _dma_dump_region(const struct ps3_dma_region *r,
	const char *func, int line)
{
	DBG("%s:%d: dev        %u:%u\n", func, line, r->dev->bus_id,
		r->dev->dev_id);
	DBG("%s:%d: page_size  %u\n", func, line, r->page_size);
	DBG("%s:%d: bus_addr   %lxh\n", func, line, r->bus_addr);
	DBG("%s:%d: len        %lxh\n", func, line, r->len);
	DBG("%s:%d: offset     %lxh\n", func, line, r->offset);
}

  /**
 * dma_chunk - A chunk of dma pages mapped by the io controller.
 * @region - The dma region that owns this chunk.
 * @lpar_addr: Starting lpar address of the area to map.
 * @bus_addr: Starting ioc bus address of the area to map.
 * @len: Length in bytes of the area to map.
 * @link: A struct list_head used with struct ps3_dma_region.chunk_list, the
 * list of all chuncks owned by the region.
 *
 * This implementation uses a very simple dma page manager
 * based on the dma_chunk structure.  This scheme assumes
 * that all drivers use very well behaved dma ops.
 */

struct dma_chunk {
	struct ps3_dma_region *region;
	unsigned long lpar_addr;
	unsigned long bus_addr;
	unsigned long len;
	struct list_head link;
	unsigned int usage_count;
};

#define dma_dump_chunk(_a) _dma_dump_chunk(_a, __func__, __LINE__)
static void _dma_dump_chunk (const struct dma_chunk* c, const char* func,
	int line)
{
	DBG("%s:%d: r.dev        %u:%u\n", func, line,
		c->region->dev->bus_id, c->region->dev->dev_id);
	DBG("%s:%d: r.bus_addr   %lxh\n", func, line, c->region->bus_addr);
	DBG("%s:%d: r.page_size  %u\n", func, line, c->region->page_size);
	DBG("%s:%d: r.len        %lxh\n", func, line, c->region->len);
	DBG("%s:%d: r.offset     %lxh\n", func, line, c->region->offset);
	DBG("%s:%d: c.lpar_addr  %lxh\n", func, line, c->lpar_addr);
	DBG("%s:%d: c.bus_addr   %lxh\n", func, line, c->bus_addr);
	DBG("%s:%d: c.len        %lxh\n", func, line, c->len);
}

static struct dma_chunk * dma_find_chunk(struct ps3_dma_region *r,
	unsigned long bus_addr, unsigned long len)
{
	struct dma_chunk *c;
	unsigned long aligned_bus = _ALIGN_DOWN(bus_addr, 1 << r->page_size);