https://github.com/torvalds/linux
Tip revision: b7b275e60bcd5f89771e865a8239325f86d9927d authored by Linus Torvalds on 27 November 2022, 21:31:48 UTC
Linux 6.1-rc7
Linux 6.1-rc7
Tip revision: b7b275e
dc21285.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/arch/arm/kernel/dec21285.c: PCI functions for DC21285
*
* Copyright (C) 1998-2001 Russell King
* Copyright (C) 1998-2000 Phil Blundell
*/
#include <linux/dma-map-ops.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/spinlock.h>
#include <asm/irq.h>
#include <asm/mach/pci.h>
#include <asm/hardware/dec21285.h>
#define MAX_SLOTS 21
#define PCICMD_ABORT ((PCI_STATUS_REC_MASTER_ABORT| \
PCI_STATUS_REC_TARGET_ABORT)<<16)
#define PCICMD_ERROR_BITS ((PCI_STATUS_DETECTED_PARITY | \
PCI_STATUS_REC_MASTER_ABORT | \
PCI_STATUS_REC_TARGET_ABORT | \
PCI_STATUS_PARITY) << 16)
extern int setup_arm_irq(int, struct irqaction *);
static unsigned long
dc21285_base_address(struct pci_bus *bus, unsigned int devfn)
{
unsigned long addr = 0;
if (bus->number == 0) {
if (PCI_SLOT(devfn) == 0)
/*
* For devfn 0, point at the 21285
*/
addr = ARMCSR_BASE;
else {
devfn -= 1 << 3;
if (devfn < PCI_DEVFN(MAX_SLOTS, 0))
addr = PCICFG0_BASE | 0xc00000 | (devfn << 8);
}
} else
addr = PCICFG1_BASE | (bus->number << 16) | (devfn << 8);
return addr;
}
static int
dc21285_read_config(struct pci_bus *bus, unsigned int devfn, int where,
int size, u32 *value)
{
unsigned long addr = dc21285_base_address(bus, devfn);
u32 v = 0xffffffff;
if (addr)
switch (size) {
case 1:
asm volatile("ldrb %0, [%1, %2]"
: "=r" (v) : "r" (addr), "r" (where) : "cc");
break;
case 2:
asm volatile("ldrh %0, [%1, %2]"
: "=r" (v) : "r" (addr), "r" (where) : "cc");
break;
case 4:
asm volatile("ldr %0, [%1, %2]"
: "=r" (v) : "r" (addr), "r" (where) : "cc");
break;
}
*value = v;
v = *CSR_PCICMD;
if (v & PCICMD_ABORT) {
*CSR_PCICMD = v & (0xffff|PCICMD_ABORT);
return -1;
}
return PCIBIOS_SUCCESSFUL;
}
static int
dc21285_write_config(struct pci_bus *bus, unsigned int devfn, int where,
int size, u32 value)
{
unsigned long addr = dc21285_base_address(bus, devfn);
u32 v;
if (addr)
switch (size) {
case 1:
asm volatile("strb %0, [%1, %2]"
: : "r" (value), "r" (addr), "r" (where)
: "cc");
break;
case 2:
asm volatile("strh %0, [%1, %2]"
: : "r" (value), "r" (addr), "r" (where)
: "cc");
break;
case 4:
asm volatile("str %0, [%1, %2]"
: : "r" (value), "r" (addr), "r" (where)
: "cc");
break;
}
v = *CSR_PCICMD;
if (v & PCICMD_ABORT) {
*CSR_PCICMD = v & (0xffff|PCICMD_ABORT);
return -1;
}
return PCIBIOS_SUCCESSFUL;
}
struct pci_ops dc21285_ops = {
.read = dc21285_read_config,
.write = dc21285_write_config,
};
static struct timer_list serr_timer;
static struct timer_list perr_timer;
static void dc21285_enable_error(struct timer_list *timer)
{
del_timer(timer);
if (timer == &serr_timer)
enable_irq(IRQ_PCI_SERR);
else if (timer == &perr_timer)
enable_irq(IRQ_PCI_PERR);
}
/*
* Warn on PCI errors.
*/
static irqreturn_t dc21285_abort_irq(int irq, void *dev_id)
{
unsigned int cmd;
unsigned int status;
cmd = *CSR_PCICMD;
status = cmd >> 16;
cmd = cmd & 0xffff;
if (status & PCI_STATUS_REC_MASTER_ABORT) {
printk(KERN_DEBUG "PCI: master abort, pc=0x%08lx\n",
instruction_pointer(get_irq_regs()));
cmd |= PCI_STATUS_REC_MASTER_ABORT << 16;
}
if (status & PCI_STATUS_REC_TARGET_ABORT) {
printk(KERN_DEBUG "PCI: target abort: ");
pcibios_report_status(PCI_STATUS_REC_MASTER_ABORT |
PCI_STATUS_SIG_TARGET_ABORT |
PCI_STATUS_REC_TARGET_ABORT, 1);
printk("\n");
cmd |= PCI_STATUS_REC_TARGET_ABORT << 16;
}
*CSR_PCICMD = cmd;
return IRQ_HANDLED;
}
static irqreturn_t dc21285_serr_irq(int irq, void *dev_id)
{
struct timer_list *timer = dev_id;
unsigned int cntl;
printk(KERN_DEBUG "PCI: system error received: ");
pcibios_report_status(PCI_STATUS_SIG_SYSTEM_ERROR, 1);
printk("\n");
cntl = *CSR_SA110_CNTL & 0xffffdf07;
*CSR_SA110_CNTL = cntl | SA110_CNTL_RXSERR;
/*
* back off this interrupt
*/
disable_irq(irq);
timer->expires = jiffies + HZ;
add_timer(timer);
return IRQ_HANDLED;
}
static irqreturn_t dc21285_discard_irq(int irq, void *dev_id)
{
printk(KERN_DEBUG "PCI: discard timer expired\n");
*CSR_SA110_CNTL &= 0xffffde07;
return IRQ_HANDLED;
}
static irqreturn_t dc21285_dparity_irq(int irq, void *dev_id)
{
unsigned int cmd;
printk(KERN_DEBUG "PCI: data parity error detected: ");
pcibios_report_status(PCI_STATUS_PARITY | PCI_STATUS_DETECTED_PARITY, 1);
printk("\n");
cmd = *CSR_PCICMD & 0xffff;
*CSR_PCICMD = cmd | 1 << 24;
return IRQ_HANDLED;
}
static irqreturn_t dc21285_parity_irq(int irq, void *dev_id)
{
struct timer_list *timer = dev_id;
unsigned int cmd;
printk(KERN_DEBUG "PCI: parity error detected: ");
pcibios_report_status(PCI_STATUS_PARITY | PCI_STATUS_DETECTED_PARITY, 1);
printk("\n");
cmd = *CSR_PCICMD & 0xffff;
*CSR_PCICMD = cmd | 1 << 31;
/*
* back off this interrupt
*/
disable_irq(irq);
timer->expires = jiffies + HZ;
add_timer(timer);
return IRQ_HANDLED;
}
static int dc21285_pci_bus_notifier(struct notifier_block *nb,
unsigned long action,
void *data)
{
if (action != BUS_NOTIFY_ADD_DEVICE)
return NOTIFY_DONE;
dma_direct_set_offset(data, PHYS_OFFSET, BUS_OFFSET, SZ_256M);
return NOTIFY_OK;
}
static struct notifier_block dc21285_pci_bus_nb = {
.notifier_call = dc21285_pci_bus_notifier,
};
int __init dc21285_setup(int nr, struct pci_sys_data *sys)
{
struct resource *res;
res = kcalloc(2, sizeof(struct resource), GFP_KERNEL);
if (!res) {
printk("out of memory for root bus resources");
return 0;
}
res[0].flags = IORESOURCE_MEM;
res[0].name = "Footbridge non-prefetch";
res[1].flags = IORESOURCE_MEM | IORESOURCE_PREFETCH;
res[1].name = "Footbridge prefetch";
allocate_resource(&iomem_resource, &res[1], 0x20000000,
0xa0000000, 0xffffffff, 0x20000000, NULL, NULL);
allocate_resource(&iomem_resource, &res[0], 0x40000000,
0x80000000, 0xffffffff, 0x40000000, NULL, NULL);
sys->mem_offset = DC21285_PCI_MEM;
pci_add_resource_offset(&sys->resources, &res[0], sys->mem_offset);
pci_add_resource_offset(&sys->resources, &res[1], sys->mem_offset);
bus_register_notifier(&pci_bus_type, &dc21285_pci_bus_nb);
return 1;
}
#define dc21285_request_irq(_a, _b, _c, _d, _e) \
WARN_ON(request_irq(_a, _b, _c, _d, _e) < 0)
void __init dc21285_preinit(void)
{
unsigned int mem_size, mem_mask;
pcibios_min_mem = 0x81000000;
mem_size = (unsigned int)high_memory - PAGE_OFFSET;
for (mem_mask = 0x00100000; mem_mask < 0x10000000; mem_mask <<= 1)
if (mem_mask >= mem_size)
break;
/*
* These registers need to be set up whether we're the
* central function or not.
*/
*CSR_SDRAMBASEMASK = (mem_mask - 1) & 0x0ffc0000;
*CSR_SDRAMBASEOFFSET = 0;
*CSR_ROMBASEMASK = 0x80000000;
*CSR_CSRBASEMASK = 0;
*CSR_CSRBASEOFFSET = 0;
*CSR_PCIADDR_EXTN = 0;
printk(KERN_INFO "PCI: DC21285 footbridge, revision %02lX, in "
"central function mode\n", *CSR_CLASSREV & 0xff);
/*
* Clear any existing errors - we aren't
* interested in historical data...
*/
*CSR_SA110_CNTL = (*CSR_SA110_CNTL & 0xffffde07) | SA110_CNTL_RXSERR;
*CSR_PCICMD = (*CSR_PCICMD & 0xffff) | PCICMD_ERROR_BITS;
timer_setup(&serr_timer, dc21285_enable_error, 0);
timer_setup(&perr_timer, dc21285_enable_error, 0);
/*
* We don't care if these fail.
*/
dc21285_request_irq(IRQ_PCI_SERR, dc21285_serr_irq, 0,
"PCI system error", &serr_timer);
dc21285_request_irq(IRQ_PCI_PERR, dc21285_parity_irq, 0,
"PCI parity error", &perr_timer);
dc21285_request_irq(IRQ_PCI_ABORT, dc21285_abort_irq, 0,
"PCI abort", NULL);
dc21285_request_irq(IRQ_DISCARD_TIMER, dc21285_discard_irq, 0,
"Discard timer", NULL);
dc21285_request_irq(IRQ_PCI_DPERR, dc21285_dparity_irq, 0,
"PCI data parity", NULL);
/*
* Map our SDRAM at a known address in PCI space, just in case
* the firmware had other ideas. Using a nonzero base is
* necessary, since some VGA cards forcefully use PCI addresses
* in the range 0x000a0000 to 0x000c0000. (eg, S3 cards).
*/
*CSR_PCICSRBASE = 0xf4000000;
*CSR_PCICSRIOBASE = 0;
*CSR_PCISDRAMBASE = BUS_OFFSET;
*CSR_PCIROMBASE = 0;
*CSR_PCICMD = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
PCI_COMMAND_INVALIDATE | PCICMD_ERROR_BITS;
}
void __init dc21285_postinit(void)
{
register_isa_ports(DC21285_PCI_MEM, DC21285_PCI_IO, 0);
}