kernel-ark/arch/sparc64/kernel/ebus.c
David S. Miller 9c908f97d0 [SPARC]: Fix EBUS use of uninitialized variable.
If of_get_property() fails, it returns NULL and the 'len'
parameter is undefined.  So we need to explicitly set len
to zero in such cases.

Noticed by Al Viro.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-27 13:09:28 -07:00

550 lines
13 KiB
C

/* $Id: ebus.c,v 1.64 2001/11/08 04:41:33 davem Exp $
* ebus.c: PCI to EBus bridge device.
*
* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
* Copyright (C) 1999 David S. Miller (davem@redhat.com)
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <asm/system.h>
#include <asm/page.h>
#include <asm/ebus.h>
#include <asm/oplib.h>
#include <asm/prom.h>
#include <asm/of_device.h>
#include <asm/bpp.h>
#include <asm/irq.h>
#include <asm/io.h>
/* EBUS dma library. */
#define EBDMA_CSR 0x00UL /* Control/Status */
#define EBDMA_ADDR 0x04UL /* DMA Address */
#define EBDMA_COUNT 0x08UL /* DMA Count */
#define EBDMA_CSR_INT_PEND 0x00000001
#define EBDMA_CSR_ERR_PEND 0x00000002
#define EBDMA_CSR_DRAIN 0x00000004
#define EBDMA_CSR_INT_EN 0x00000010
#define EBDMA_CSR_RESET 0x00000080
#define EBDMA_CSR_WRITE 0x00000100
#define EBDMA_CSR_EN_DMA 0x00000200
#define EBDMA_CSR_CYC_PEND 0x00000400
#define EBDMA_CSR_DIAG_RD_DONE 0x00000800
#define EBDMA_CSR_DIAG_WR_DONE 0x00001000
#define EBDMA_CSR_EN_CNT 0x00002000
#define EBDMA_CSR_TC 0x00004000
#define EBDMA_CSR_DIS_CSR_DRN 0x00010000
#define EBDMA_CSR_BURST_SZ_MASK 0x000c0000
#define EBDMA_CSR_BURST_SZ_1 0x00080000
#define EBDMA_CSR_BURST_SZ_4 0x00000000
#define EBDMA_CSR_BURST_SZ_8 0x00040000
#define EBDMA_CSR_BURST_SZ_16 0x000c0000
#define EBDMA_CSR_DIAG_EN 0x00100000
#define EBDMA_CSR_DIS_ERR_PEND 0x00400000
#define EBDMA_CSR_TCI_DIS 0x00800000
#define EBDMA_CSR_EN_NEXT 0x01000000
#define EBDMA_CSR_DMA_ON 0x02000000
#define EBDMA_CSR_A_LOADED 0x04000000
#define EBDMA_CSR_NA_LOADED 0x08000000
#define EBDMA_CSR_DEV_ID_MASK 0xf0000000
#define EBUS_DMA_RESET_TIMEOUT 10000
static void __ebus_dma_reset(struct ebus_dma_info *p, int no_drain)
{
int i;
u32 val = 0;
writel(EBDMA_CSR_RESET, p->regs + EBDMA_CSR);
udelay(1);
if (no_drain)
return;
for (i = EBUS_DMA_RESET_TIMEOUT; i > 0; i--) {
val = readl(p->regs + EBDMA_CSR);
if (!(val & (EBDMA_CSR_DRAIN | EBDMA_CSR_CYC_PEND)))
break;
udelay(10);
}
}
static irqreturn_t ebus_dma_irq(int irq, void *dev_id)
{
struct ebus_dma_info *p = dev_id;
unsigned long flags;
u32 csr = 0;
spin_lock_irqsave(&p->lock, flags);
csr = readl(p->regs + EBDMA_CSR);
writel(csr, p->regs + EBDMA_CSR);
spin_unlock_irqrestore(&p->lock, flags);
if (csr & EBDMA_CSR_ERR_PEND) {
printk(KERN_CRIT "ebus_dma(%s): DMA error!\n", p->name);
p->callback(p, EBUS_DMA_EVENT_ERROR, p->client_cookie);
return IRQ_HANDLED;
} else if (csr & EBDMA_CSR_INT_PEND) {
p->callback(p,
(csr & EBDMA_CSR_TC) ?
EBUS_DMA_EVENT_DMA : EBUS_DMA_EVENT_DEVICE,
p->client_cookie);
return IRQ_HANDLED;
}
return IRQ_NONE;
}
int ebus_dma_register(struct ebus_dma_info *p)
{
u32 csr;
if (!p->regs)
return -EINVAL;
if (p->flags & ~(EBUS_DMA_FLAG_USE_EBDMA_HANDLER |
EBUS_DMA_FLAG_TCI_DISABLE))
return -EINVAL;
if ((p->flags & EBUS_DMA_FLAG_USE_EBDMA_HANDLER) && !p->callback)
return -EINVAL;
if (!strlen(p->name))
return -EINVAL;
__ebus_dma_reset(p, 1);
csr = EBDMA_CSR_BURST_SZ_16 | EBDMA_CSR_EN_CNT;
if (p->flags & EBUS_DMA_FLAG_TCI_DISABLE)
csr |= EBDMA_CSR_TCI_DIS;
writel(csr, p->regs + EBDMA_CSR);
return 0;
}
EXPORT_SYMBOL(ebus_dma_register);
int ebus_dma_irq_enable(struct ebus_dma_info *p, int on)
{
unsigned long flags;
u32 csr;
if (on) {
if (p->flags & EBUS_DMA_FLAG_USE_EBDMA_HANDLER) {
if (request_irq(p->irq, ebus_dma_irq, IRQF_SHARED, p->name, p))
return -EBUSY;
}
spin_lock_irqsave(&p->lock, flags);
csr = readl(p->regs + EBDMA_CSR);
csr |= EBDMA_CSR_INT_EN;
writel(csr, p->regs + EBDMA_CSR);
spin_unlock_irqrestore(&p->lock, flags);
} else {
spin_lock_irqsave(&p->lock, flags);
csr = readl(p->regs + EBDMA_CSR);
csr &= ~EBDMA_CSR_INT_EN;
writel(csr, p->regs + EBDMA_CSR);
spin_unlock_irqrestore(&p->lock, flags);
if (p->flags & EBUS_DMA_FLAG_USE_EBDMA_HANDLER) {
free_irq(p->irq, p);
}
}
return 0;
}
EXPORT_SYMBOL(ebus_dma_irq_enable);
void ebus_dma_unregister(struct ebus_dma_info *p)
{
unsigned long flags;
u32 csr;
int irq_on = 0;
spin_lock_irqsave(&p->lock, flags);
csr = readl(p->regs + EBDMA_CSR);
if (csr & EBDMA_CSR_INT_EN) {
csr &= ~EBDMA_CSR_INT_EN;
writel(csr, p->regs + EBDMA_CSR);
irq_on = 1;
}
spin_unlock_irqrestore(&p->lock, flags);
if (irq_on)
free_irq(p->irq, p);
}
EXPORT_SYMBOL(ebus_dma_unregister);
int ebus_dma_request(struct ebus_dma_info *p, dma_addr_t bus_addr, size_t len)
{
unsigned long flags;
u32 csr;
int err;
if (len >= (1 << 24))
return -EINVAL;
spin_lock_irqsave(&p->lock, flags);
csr = readl(p->regs + EBDMA_CSR);
err = -EINVAL;
if (!(csr & EBDMA_CSR_EN_DMA))
goto out;
err = -EBUSY;
if (csr & EBDMA_CSR_NA_LOADED)
goto out;
writel(len, p->regs + EBDMA_COUNT);
writel(bus_addr, p->regs + EBDMA_ADDR);
err = 0;
out:
spin_unlock_irqrestore(&p->lock, flags);
return err;
}
EXPORT_SYMBOL(ebus_dma_request);
void ebus_dma_prepare(struct ebus_dma_info *p, int write)
{
unsigned long flags;
u32 csr;
spin_lock_irqsave(&p->lock, flags);
__ebus_dma_reset(p, 0);
csr = (EBDMA_CSR_INT_EN |
EBDMA_CSR_EN_CNT |
EBDMA_CSR_BURST_SZ_16 |
EBDMA_CSR_EN_NEXT);
if (write)
csr |= EBDMA_CSR_WRITE;
if (p->flags & EBUS_DMA_FLAG_TCI_DISABLE)
csr |= EBDMA_CSR_TCI_DIS;
writel(csr, p->regs + EBDMA_CSR);
spin_unlock_irqrestore(&p->lock, flags);
}
EXPORT_SYMBOL(ebus_dma_prepare);
unsigned int ebus_dma_residue(struct ebus_dma_info *p)
{
return readl(p->regs + EBDMA_COUNT);
}
EXPORT_SYMBOL(ebus_dma_residue);
unsigned int ebus_dma_addr(struct ebus_dma_info *p)
{
return readl(p->regs + EBDMA_ADDR);
}
EXPORT_SYMBOL(ebus_dma_addr);
void ebus_dma_enable(struct ebus_dma_info *p, int on)
{
unsigned long flags;
u32 orig_csr, csr;
spin_lock_irqsave(&p->lock, flags);
orig_csr = csr = readl(p->regs + EBDMA_CSR);
if (on)
csr |= EBDMA_CSR_EN_DMA;
else
csr &= ~EBDMA_CSR_EN_DMA;
if ((orig_csr & EBDMA_CSR_EN_DMA) !=
(csr & EBDMA_CSR_EN_DMA))
writel(csr, p->regs + EBDMA_CSR);
spin_unlock_irqrestore(&p->lock, flags);
}
EXPORT_SYMBOL(ebus_dma_enable);
struct linux_ebus *ebus_chain = NULL;
static inline void *ebus_alloc(size_t size)
{
void *mem;
mem = kzalloc(size, GFP_ATOMIC);
if (!mem)
panic("ebus_alloc: out of memory");
return mem;
}
static void __init fill_ebus_child(struct device_node *dp,
struct linux_ebus_child *dev,
int non_standard_regs)
{
struct of_device *op;
const int *regs;
int i, len;
dev->prom_node = dp;
printk(" (%s)", dp->name);
regs = of_get_property(dp, "reg", &len);
if (!regs)
dev->num_addrs = 0;
else
dev->num_addrs = len / sizeof(regs[0]);
if (non_standard_regs) {
/* This is to handle reg properties which are not
* in the parent relative format. One example are
* children of the i2c device on CompactPCI systems.
*
* So, for such devices we just record the property
* raw in the child resources.
*/
for (i = 0; i < dev->num_addrs; i++)
dev->resource[i].start = regs[i];
} else {
for (i = 0; i < dev->num_addrs; i++) {
int rnum = regs[i];
if (rnum >= dev->parent->num_addrs) {
prom_printf("UGH: property for %s was %d, need < %d\n",
dp->name, len, dev->parent->num_addrs);
prom_halt();
}
dev->resource[i].start = dev->parent->resource[i].start;
dev->resource[i].end = dev->parent->resource[i].end;
dev->resource[i].flags = IORESOURCE_MEM;
dev->resource[i].name = dp->name;
}
}
op = of_find_device_by_node(dp);
if (!op) {
dev->num_irqs = 0;
} else {
dev->num_irqs = op->num_irqs;
for (i = 0; i < dev->num_irqs; i++)
dev->irqs[i] = op->irqs[i];
}
if (!dev->num_irqs) {
/*
* Oh, well, some PROMs don't export interrupts
* property to children of EBus devices...
*
* Be smart about PS/2 keyboard and mouse.
*/
if (!strcmp(dev->parent->prom_node->name, "8042")) {
if (!strcmp(dev->prom_node->name, "kb_ps2")) {
dev->num_irqs = 1;
dev->irqs[0] = dev->parent->irqs[0];
} else {
dev->num_irqs = 1;
dev->irqs[0] = dev->parent->irqs[1];
}
}
}
}
static int __init child_regs_nonstandard(struct linux_ebus_device *dev)
{
if (!strcmp(dev->prom_node->name, "i2c") ||
!strcmp(dev->prom_node->name, "SUNW,lombus"))
return 1;
return 0;
}
static void __init fill_ebus_device(struct device_node *dp, struct linux_ebus_device *dev)
{
struct linux_ebus_child *child;
struct dev_archdata *sd;
struct of_device *op;
int i, len;
dev->prom_node = dp;
printk(" [%s", dp->name);
op = of_find_device_by_node(dp);
if (!op) {
dev->num_addrs = 0;
dev->num_irqs = 0;
} else {
const int *regs = of_get_property(dp, "reg", &len);
if (!regs)
len = 0;
dev->num_addrs = len / sizeof(struct linux_prom_registers);
for (i = 0; i < dev->num_addrs; i++)
memcpy(&dev->resource[i],
&op->resource[i],
sizeof(struct resource));
dev->num_irqs = op->num_irqs;
for (i = 0; i < dev->num_irqs; i++)
dev->irqs[i] = op->irqs[i];
}
sd = &dev->ofdev.dev.archdata;
sd->prom_node = dp;
sd->op = &dev->ofdev;
sd->iommu = dev->bus->ofdev.dev.parent->archdata.iommu;
sd->stc = dev->bus->ofdev.dev.parent->archdata.stc;
dev->ofdev.node = dp;
dev->ofdev.dev.parent = &dev->bus->ofdev.dev;
dev->ofdev.dev.bus = &ebus_bus_type;
sprintf(dev->ofdev.dev.bus_id, "ebus[%08x]", dp->node);
/* Register with core */
if (of_device_register(&dev->ofdev) != 0)
printk(KERN_DEBUG "ebus: device registration error for %s!\n",
dp->path_component_name);
dp = dp->child;
if (dp) {
printk(" ->");
dev->children = ebus_alloc(sizeof(struct linux_ebus_child));
child = dev->children;
child->next = NULL;
child->parent = dev;
child->bus = dev->bus;
fill_ebus_child(dp, child,
child_regs_nonstandard(dev));
while ((dp = dp->sibling) != NULL) {
child->next = ebus_alloc(sizeof(struct linux_ebus_child));
child = child->next;
child->next = NULL;
child->parent = dev;
child->bus = dev->bus;
fill_ebus_child(dp, child,
child_regs_nonstandard(dev));
}
}
printk("]");
}
static struct pci_dev *find_next_ebus(struct pci_dev *start, int *is_rio_p)
{
struct pci_dev *pdev = start;
while ((pdev = pci_get_device(PCI_VENDOR_ID_SUN, PCI_ANY_ID, pdev)))
if (pdev->device == PCI_DEVICE_ID_SUN_EBUS ||
pdev->device == PCI_DEVICE_ID_SUN_RIO_EBUS)
break;
*is_rio_p = !!(pdev && (pdev->device == PCI_DEVICE_ID_SUN_RIO_EBUS));
return pdev;
}
void __init ebus_init(void)
{
struct linux_ebus_device *dev;
struct linux_ebus *ebus;
struct pci_dev *pdev;
struct device_node *dp;
int is_rio;
int num_ebus = 0;
pdev = find_next_ebus(NULL, &is_rio);
if (!pdev) {
printk("ebus: No EBus's found.\n");
return;
}
dp = pci_device_to_OF_node(pdev);
ebus_chain = ebus = ebus_alloc(sizeof(struct linux_ebus));
ebus->next = NULL;
ebus->is_rio = is_rio;
while (dp) {
struct device_node *child;
/* SUNW,pci-qfe uses four empty ebuses on it.
I think we should not consider them here,
as they have half of the properties this
code expects and once we do PCI hot-plug,
we'd have to tweak with the ebus_chain
in the runtime after initialization. -jj */
if (!dp->child) {
pdev = find_next_ebus(pdev, &is_rio);
if (!pdev) {
if (ebus == ebus_chain) {
ebus_chain = NULL;
printk("ebus: No EBus's found.\n");
return;
}
break;
}
ebus->is_rio = is_rio;
dp = pci_device_to_OF_node(pdev);
continue;
}
printk("ebus%d:", num_ebus);
ebus->index = num_ebus;
ebus->prom_node = dp;
ebus->self = pdev;
ebus->ofdev.node = dp;
ebus->ofdev.dev.parent = &pdev->dev;
ebus->ofdev.dev.bus = &ebus_bus_type;
sprintf(ebus->ofdev.dev.bus_id, "ebus%d", num_ebus);
/* Register with core */
if (of_device_register(&ebus->ofdev) != 0)
printk(KERN_DEBUG "ebus: device registration error for %s!\n",
dp->path_component_name);
child = dp->child;
if (!child)
goto next_ebus;
ebus->devices = ebus_alloc(sizeof(struct linux_ebus_device));
dev = ebus->devices;
dev->next = NULL;
dev->children = NULL;
dev->bus = ebus;
fill_ebus_device(child, dev);
while ((child = child->sibling) != NULL) {
dev->next = ebus_alloc(sizeof(struct linux_ebus_device));
dev = dev->next;
dev->next = NULL;
dev->children = NULL;
dev->bus = ebus;
fill_ebus_device(child, dev);
}
next_ebus:
printk("\n");
pdev = find_next_ebus(pdev, &is_rio);
if (!pdev)
break;
dp = pci_device_to_OF_node(pdev);
ebus->next = ebus_alloc(sizeof(struct linux_ebus));
ebus = ebus->next;
ebus->next = NULL;
ebus->is_rio = is_rio;
++num_ebus;
}
pci_dev_put(pdev); /* XXX for the case, when ebusnd is 0, is it OK? */
}