sworks-agp.c

linux-2.6.15.6

/*
 * Serverworks AGPGART routines.
 */

#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/agp_backend.h>
#include "agp.h"

#define SVWRKS_COMMAND		0x04
#define SVWRKS_APSIZE		0x10
#define SVWRKS_MMBASE		0x14
#define SVWRKS_CACHING		0x4b
#define SVWRKS_AGP_ENABLE	0x60
#define SVWRKS_FEATURE		0x68

#define SVWRKS_SIZE_MASK	0xfe000000

/* Memory mapped registers */
#define SVWRKS_GART_CACHE	0x02
#define SVWRKS_GATTBASE		0x04
#define SVWRKS_TLBFLUSH		0x10
#define SVWRKS_POSTFLUSH	0x14
#define SVWRKS_DIRFLUSH		0x0c


struct serverworks_page_map {
	unsigned long *real;
	unsigned long __iomem *remapped;
};

static struct _serverworks_private {
	struct pci_dev *svrwrks_dev;	/* device one */
	volatile u8 __iomem *registers;
	struct serverworks_page_map **gatt_pages;
	int num_tables;
	struct serverworks_page_map scratch_dir;

	int gart_addr_ofs;
	int mm_addr_ofs;
} serverworks_private;

static int serverworks_create_page_map(struct serverworks_page_map *page_map)
{
	int i;

	page_map->real = (unsigned long *) __get_free_page(GFP_KERNEL);
	if (page_map->real == NULL) {
		return -ENOMEM;
	}
	SetPageReserved(virt_to_page(page_map->real));
	global_cache_flush();
	page_map->remapped = ioremap_nocache(virt_to_gart(page_map->real),
					    PAGE_SIZE);
	if (page_map->remapped == NULL) {
		ClearPageReserved(virt_to_page(page_map->real));
		free_page((unsigned long) page_map->real);
		page_map->real = NULL;
		return -ENOMEM;
	}
	global_cache_flush();

	for(i = 0; i < PAGE_SIZE / sizeof(unsigned long); i++)
		writel(agp_bridge->scratch_page, page_map->remapped+i);

	return 0;
}

static void serverworks_free_page_map(struct serverworks_page_map *page_map)
{
	iounmap(page_map->remapped);
	ClearPageReserved(virt_to_page(page_map->real));
	free_page((unsigned long) page_map->real);
}

static void serverworks_free_gatt_pages(void)
{
	int i;
	struct serverworks_page_map **tables;
	struct serverworks_page_map *entry;

	tables = serverworks_private.gatt_pages;
	for(i = 0; i < serverworks_private.num_tables; i++) {
		entry = tables[i];
		if (entry != NULL) {
			if (entry->real != NULL) {
				serverworks_free_page_map(entry);
			}
			kfree(entry);
		}
	}
	kfree(tables);
}

static int serverworks_create_gatt_pages(int nr_tables)
{
	struct serverworks_page_map **tables;
	struct serverworks_page_map *entry;
	int retval = 0;
	int i;

	tables = kzalloc((nr_tables + 1) * sizeof(struct serverworks_page_map *), 
			 GFP_KERNEL);
	if (tables == NULL)
		return -ENOMEM;

	for (i = 0; i < nr_tables; i++) {
		entry = kzalloc(sizeof(struct serverworks_page_map), GFP_KERNEL);
		if (entry == NULL) {
			retval = -ENOMEM;
			break;
		}
		tables[i] = entry;
		retval = serverworks_create_page_map(entry);
		if (retval != 0) break;
	}
	serverworks_private.num_tables = nr_tables;
	serverworks_private.gatt_pages = tables;

	if (retval != 0) serverworks_free_gatt_pages();

	return retval;
}

#define SVRWRKS_GET_GATT(addr) (serverworks_private.gatt_pages[\
	GET_PAGE_DIR_IDX(addr)]->remapped)

#ifndef GET_PAGE_DIR_OFF
#define GET_PAGE_DIR_OFF(addr) (addr >> 22)
#endif

#ifndef GET_PAGE_DIR_IDX
#define GET_PAGE_DIR_IDX(addr) (GET_PAGE_DIR_OFF(addr) - \
	GET_PAGE_DIR_OFF(agp_bridge->gart_bus_addr))
#endif

#ifndef GET_GATT_OFF
#define GET_GATT_OFF(addr) ((addr & 0x003ff000) >> 12)
#endif

static int serverworks_create_gatt_table(struct agp_bridge_data *bridge)
{
	struct aper_size_info_lvl2 *value;
	struct serverworks_page_map page_dir;
	int retval;
	u32 temp;
	int i;

	value = A_SIZE_LVL2(agp_bridge->current_size);
	retval = serverworks_create_page_map(&page_dir);
	if (retval != 0) {
		return retval;
	}
	retval = serverworks_create_page_map(&serverworks_private.scratch_dir);
	if (retval != 0) {
		serverworks_free_page_map(&page_dir);
		return retval;
	}
	/* Create a fake scratch directory */
	for(i = 0; i < 1024; i++) {
		writel(agp_bridge->scratch_page, serverworks_private.scratch_dir.remapped+i);
		writel(virt_to_gart(serverworks_private.scratch_dir.real) | 1, page_dir.remapped+i);
	}

	retval = serverworks_create_gatt_pages(value->num_entries / 1024);
	if (retval != 0) {
		serverworks_free_page_map(&page_dir);
		serverworks_free_page_map(&serverworks_private.scratch_dir);
		return retval;
	}

	agp_bridge->gatt_table_real = (u32 *)page_dir.real;
	agp_bridge->gatt_table = (u32 __iomem *)page_dir.remapped;
	agp_bridge->gatt_bus_addr = virt_to_gart(page_dir.real);

	/* Get the address for the gart region.
	 * This is a bus address even on the alpha, b/c its
	 * used to program the agp master not the cpu
	 */

	pci_read_config_dword(agp_bridge->dev,serverworks_private.gart_addr_ofs,&temp);
	agp_bridge->gart_bus_addr = (temp & PCI_BASE_ADDRESS_MEM_MASK);

	/* Calculate the agp offset */	

	for(i = 0; i < value->num_entries / 1024; i++)
		writel(virt_to_gart(serverworks_private.gatt_pages[i]->real)|1, page_dir.remapped+i);

	return 0;
}

static int serverworks_free_gatt_table(struct agp_bridge_data *bridge)
{
	struct serverworks_page_map page_dir;
   
	page_dir.real = (unsigned long *)agp_bridge->gatt_table_real;
	page_dir.remapped = (unsigned long __iomem *)agp_bridge->gatt_table;

	serverworks_free_gatt_pages();
	serverworks_free_page_map(&page_dir);
	serverworks_free_page_map(&serverworks_private.scratch_dir);
	return 0;
}

static int serverworks_fetch_size(void)
{
	int i;
	u32 temp;
	u32 temp2;
	struct aper_size_info_lvl2 *values;

	values = A_SIZE_LVL2(agp_bridge->driver->aperture_sizes);
	pci_read_config_dword(agp_bridge->dev,serverworks_private.gart_addr_ofs,&temp);
	pci_write_config_dword(agp_bridge->dev,serverworks_private.gart_addr_ofs,
					SVWRKS_SIZE_MASK);
	pci_read_config_dword(agp_bridge->dev,serverworks_private.gart_addr_ofs,&temp2);
	pci_write_config_dword(agp_bridge->dev,serverworks_private.gart_addr_ofs,temp);
	temp2 &= SVWRKS_SIZE_MASK;

	for (i = 0; i < agp_bridge->driver->num_aperture_sizes; i++) {
		if (temp2 == values[i].size_value) {
			agp_bridge->previous_size =
			    agp_bridge->current_size = (void *) (values + i);

			agp_bridge->aperture_size_idx = i;
			return values[i].size;
		}
	}

	return 0;
}

/*
 * This routine could be implemented by taking the addresses
 * written to the GATT, and flushing them individually.  However
 * currently it just flushes the whole table.  Which is probably
 * more efficent, since agp_memory blocks can be a large number of
 * entries.
 */
static void serverworks_tlbflush(struct agp_memory *temp)
{
	unsigned long timeout;

	writeb(1, serverworks_private.registers+SVWRKS_POSTFLUSH);
	timeout = jiffies + 3*HZ;
	while (readb(serverworks_private.registers+SVWRKS_POSTFLUSH) == 1) {
		cpu_relax();
		if (time_after(jiffies, timeout)) {
			printk(KERN_ERR PFX "TLB post flush took more than 3 seconds\n");
			break;
		}
	}

	writel(1, serverworks_private.registers+SVWRKS_DIRFLUSH);
	timeout = jiffies + 3*HZ;
	while (readl(serverworks_private.registers+SVWRKS_DIRFLUSH) == 1) {
		cpu_relax();
		if (time_after(jiffies, timeout)) {
			printk(KERN_ERR PFX "TLB Dir flush took more than 3 seconds\n");
			break;
		}
	}
}

static int serverworks_configure(void)
{
	struct aper_size_info_lvl2 *current_size;
	u32 temp;
	u8 enable_reg;
	u16 cap_reg;

	current_size = A_SIZE_LVL2(agp_bridge->current_size);

	/* Get the memory mapped registers */
	pci_read_config_dword(agp_bridge->dev, serverworks_private.mm_addr_ofs, &temp);
	temp = (temp & PCI_BASE_ADDRESS_MEM_MASK);
	serverworks_private.registers = (volatile u8 __iomem *) ioremap(temp, 4096);
	if (!serverworks_private.registers) {
		printk (KERN_ERR PFX "Unable to ioremap() memory.\n");
		return -ENOMEM;
	}

	writeb(0xA, serverworks_private.registers+SVWRKS_GART_CACHE);