[deliverable/linux.git] / arch / x86 / pci / mmconfig_64.c

/*
 * mmconfig.c - Low-level direct PCI config space access via MMCONFIG
 *
 * This is an 64bit optimized version that always keeps the full mmconfig
 * space mapped. This allows lockless config space operation.
 */

#include <linux/pci.h>
#include <linux/init.h>
#include <linux/acpi.h>
#include <linux/bitmap.h>
#include <asm/e820.h>
#include <asm/pci_x86.h>

/* Static virtual mapping of the MMCONFIG aperture */
struct mmcfg_virt {
	struct pci_mmcfg_region *cfg;
	char __iomem *virt;
};
static struct mmcfg_virt *pci_mmcfg_virt;

static char __iomem *get_virt(unsigned int seg, unsigned bus)
{
	struct pci_mmcfg_region *cfg;
	int cfg_num;

	for (cfg_num = 0; cfg_num < pci_mmcfg_config_num; cfg_num++) {
		cfg = pci_mmcfg_virt[cfg_num].cfg;
		if (cfg->segment == seg &&
		    (cfg->start_bus <= bus) &&
		    (cfg->end_bus >= bus))
			return pci_mmcfg_virt[cfg_num].virt;
	}

	/* Fall back to type 0 */
	return NULL;
}

static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn)
{
	char __iomem *addr;

	addr = get_virt(seg, bus);
	if (!addr)
		return NULL;
	return addr + (PCI_MMCFG_BUS_OFFSET(bus) | (devfn << 12));
}

static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
			  unsigned int devfn, int reg, int len, u32 *value)
{
	char __iomem *addr;

	/* Why do we have this when nobody checks it. How about a BUG()!? -AK */
	if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) {
err:		*value = -1;
		return -EINVAL;
	}

	addr = pci_dev_base(seg, bus, devfn);
	if (!addr)
		goto err;

	switch (len) {
	case 1:
		*value = mmio_config_readb(addr + reg);
		break;
	case 2:
		*value = mmio_config_readw(addr + reg);
		break;
	case 4:
		*value = mmio_config_readl(addr + reg);
		break;
	}

	return 0;
}

static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
			   unsigned int devfn, int reg, int len, u32 value)
{
	char __iomem *addr;

	/* Why do we have this when nobody checks it. How about a BUG()!? -AK */
	if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
		return -EINVAL;

	addr = pci_dev_base(seg, bus, devfn);
	if (!addr)
		return -EINVAL;

	switch (len) {
	case 1:
		mmio_config_writeb(addr + reg, value);
		break;
	case 2:
		mmio_config_writew(addr + reg, value);
		break;
	case 4:
		mmio_config_writel(addr + reg, value);
		break;
	}

	return 0;
}

static struct pci_raw_ops pci_mmcfg = {
	.read =		pci_mmcfg_read,
	.write =	pci_mmcfg_write,
};

static void __iomem * __init mcfg_ioremap(struct pci_mmcfg_region *cfg)
{
	void __iomem *addr;
	u64 start, size;
	int num_buses;

	start = cfg->address + PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
	num_buses = cfg->end_bus - cfg->start_bus + 1;
	size = PCI_MMCFG_BUS_OFFSET(num_buses);
	addr = ioremap_nocache(start, size);
	if (addr) {
		printk(KERN_INFO "PCI: Using MMCONFIG at %Lx - %Lx\n",
		       start, start + size - 1);
		addr -= PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
	}
	return addr;
}

int __init pci_mmcfg_arch_init(void)
{
	int i;
	pci_mmcfg_virt = kzalloc(sizeof(*pci_mmcfg_virt) *
				 pci_mmcfg_config_num, GFP_KERNEL);
	if (pci_mmcfg_virt == NULL) {
		printk(KERN_ERR "PCI: Can not allocate memory for mmconfig structures\n");
		return 0;
	}

	for (i = 0; i < pci_mmcfg_config_num; ++i) {
		pci_mmcfg_virt[i].cfg = &pci_mmcfg_config[i];
		pci_mmcfg_virt[i].virt = mcfg_ioremap(&pci_mmcfg_config[i]);
		if (!pci_mmcfg_virt[i].virt) {
			printk(KERN_ERR "PCI: Cannot map mmconfig aperture for "
					"segment %d\n",
				pci_mmcfg_config[i].segment);
			pci_mmcfg_arch_free();
			return 0;
		}
	}
	raw_pci_ext_ops = &pci_mmcfg;
	return 1;
}

void __init pci_mmcfg_arch_free(void)
{
	int i;

	if (pci_mmcfg_virt == NULL)
		return;

	for (i = 0; i < pci_mmcfg_config_num; ++i) {
		if (pci_mmcfg_virt[i].virt) {
			iounmap(pci_mmcfg_virt[i].virt + PCI_MMCFG_BUS_OFFSET(pci_mmcfg_virt[i].cfg->start_bus));
			pci_mmcfg_virt[i].virt = NULL;
			pci_mmcfg_virt[i].cfg = NULL;
		}
	}

	kfree(pci_mmcfg_virt);
	pci_mmcfg_virt = NULL;
}
Commit	Line	Data
	1	/*
	2	* mmconfig.c - Low-level direct PCI config space access via MMCONFIG
	3	*
	4	* This is an 64bit optimized version that always keeps the full mmconfig
	5	* space mapped. This allows lockless config space operation.
	6	*/
	7
	8	#include <linux/pci.h>
	9	#include <linux/init.h>
	10	#include <linux/acpi.h>
	11	#include <linux/bitmap.h>
	12	#include <asm/e820.h>
	13	#include <asm/pci_x86.h>
	14
	15	/* Static virtual mapping of the MMCONFIG aperture */
	16	struct mmcfg_virt {
	17	struct pci_mmcfg_region *cfg;
	18	char __iomem *virt;
	19	};
	20	static struct mmcfg_virt *pci_mmcfg_virt;
	21
	22	static char __iomem *get_virt(unsigned int seg, unsigned bus)
	23	{
	24	struct pci_mmcfg_region *cfg;
	25	int cfg_num;
	26
	27	for (cfg_num = 0; cfg_num < pci_mmcfg_config_num; cfg_num++) {
	28	cfg = pci_mmcfg_virt[cfg_num].cfg;
	29	if (cfg->segment == seg &&
	30	(cfg->start_bus <= bus) &&
	31	(cfg->end_bus >= bus))
	32	return pci_mmcfg_virt[cfg_num].virt;
	33	}
	34
	35	/* Fall back to type 0 */
	36	return NULL;
	37	}
	38
	39	static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn)
	40	{
	41	char __iomem *addr;
	42
	43	addr = get_virt(seg, bus);
	44	if (!addr)
	45	return NULL;
	46	return addr + (PCI_MMCFG_BUS_OFFSET(bus) \| (devfn << 12));
	47	}
	48
	49	static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
	50	unsigned int devfn, int reg, int len, u32 *value)
	51	{
	52	char __iomem *addr;
	53
	54	/* Why do we have this when nobody checks it. How about a BUG()!? -AK */
	55	if (unlikely((bus > 255) \|\| (devfn > 255) \|\| (reg > 4095))) {
	56	err: *value = -1;
	57	return -EINVAL;
	58	}
	59
	60	addr = pci_dev_base(seg, bus, devfn);
	61	if (!addr)
	62	goto err;
	63
	64	switch (len) {
	65	case 1:
	66	*value = mmio_config_readb(addr + reg);
	67	break;
	68	case 2:
	69	*value = mmio_config_readw(addr + reg);
	70	break;
	71	case 4:
	72	*value = mmio_config_readl(addr + reg);
	73	break;
	74	}
	75
	76	return 0;
	77	}
	78
	79	static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
	80	unsigned int devfn, int reg, int len, u32 value)
	81	{
	82	char __iomem *addr;
	83
	84	/* Why do we have this when nobody checks it. How about a BUG()!? -AK */
	85	if (unlikely((bus > 255) \|\| (devfn > 255) \|\| (reg > 4095)))
	86	return -EINVAL;
	87
	88	addr = pci_dev_base(seg, bus, devfn);
	89	if (!addr)
	90	return -EINVAL;
	91
	92	switch (len) {
	93	case 1:
	94	mmio_config_writeb(addr + reg, value);
	95	break;
	96	case 2:
	97	mmio_config_writew(addr + reg, value);
	98	break;
	99	case 4:
	100	mmio_config_writel(addr + reg, value);
	101	break;
	102	}
	103
	104	return 0;
	105	}
	106
	107	static struct pci_raw_ops pci_mmcfg = {
	108	.read = pci_mmcfg_read,
	109	.write = pci_mmcfg_write,
	110	};
	111
	112	static void __iomem * __init mcfg_ioremap(struct pci_mmcfg_region *cfg)
	113	{
	114	void __iomem *addr;
	115	u64 start, size;
	116	int num_buses;
	117
	118	start = cfg->address + PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
	119	num_buses = cfg->end_bus - cfg->start_bus + 1;
	120	size = PCI_MMCFG_BUS_OFFSET(num_buses);
	121	addr = ioremap_nocache(start, size);
	122	if (addr) {
	123	printk(KERN_INFO "PCI: Using MMCONFIG at %Lx - %Lx\n",
	124	start, start + size - 1);
	125	addr -= PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
	126	}
	127	return addr;
	128	}
	129
	130	int __init pci_mmcfg_arch_init(void)
	131	{
	132	int i;
	133	pci_mmcfg_virt = kzalloc(sizeof(pci_mmcfg_virt)
	134	pci_mmcfg_config_num, GFP_KERNEL);
	135	if (pci_mmcfg_virt == NULL) {
	136	printk(KERN_ERR "PCI: Can not allocate memory for mmconfig structures\n");
	137	return 0;
	138	}
	139
	140	for (i = 0; i < pci_mmcfg_config_num; ++i) {
	141	pci_mmcfg_virt[i].cfg = &pci_mmcfg_config[i];
	142	pci_mmcfg_virt[i].virt = mcfg_ioremap(&pci_mmcfg_config[i]);
	143	if (!pci_mmcfg_virt[i].virt) {
	144	printk(KERN_ERR "PCI: Cannot map mmconfig aperture for "
	145	"segment %d\n",
	146	pci_mmcfg_config[i].segment);
	147	pci_mmcfg_arch_free();
	148	return 0;
	149	}
	150	}
	151	raw_pci_ext_ops = &pci_mmcfg;
	152	return 1;
	153	}
	154
	155	void __init pci_mmcfg_arch_free(void)
	156	{
	157	int i;
	158
	159	if (pci_mmcfg_virt == NULL)
	160	return;
	161
	162	for (i = 0; i < pci_mmcfg_config_num; ++i) {
	163	if (pci_mmcfg_virt[i].virt) {
	164	iounmap(pci_mmcfg_virt[i].virt + PCI_MMCFG_BUS_OFFSET(pci_mmcfg_virt[i].cfg->start_bus));
	165	pci_mmcfg_virt[i].virt = NULL;
	166	pci_mmcfg_virt[i].cfg = NULL;
	167	}
	168	}
	169
	170	kfree(pci_mmcfg_virt);
	171	pci_mmcfg_virt = NULL;
	172	}