// SPDX-License-Identifier: GPL-2.0
/*
* Low-Level PCI Support for the SH7780
*
* Copyright (C) 2005 - 2010 Paul Mundt
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/irq.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/log2.h>
#include "pci-sh4.h"
#include <asm/mmu.h>
#include <linux/sizes.h>
#if defined(CONFIG_CPU_BIG_ENDIAN)
# define PCICR_ENDIANNESS SH4_PCICR_BSWP
#else
# define PCICR_ENDIANNESS 0
#endif
static struct resource sh7785_pci_resources[] = {
{
.name = "PCI IO",
.start = 0x1000,
.end = SZ_4M - 1,
.flags = IORESOURCE_IO,
}, {
.name = "PCI MEM 0",
.start = 0xfd000000,
.end = 0xfd000000 + SZ_16M - 1,
.flags = IORESOURCE_MEM,
}, {
.name = "PCI MEM 1",
.start = 0x10000000,
.end = 0x10000000 + SZ_64M - 1,
.flags = IORESOURCE_MEM,
}, {
/*
* 32-bit only resources must be last.
*/
.name = "PCI MEM 2",
.start = 0xc0000000,
.end = 0xc0000000 + SZ_512M - 1,
.flags = IORESOURCE_MEM | IORESOURCE_MEM_32BIT,
},
};
static struct pci_channel sh7780_pci_controller = {
.pci_ops = &sh4_pci_ops,
.resources = sh7785_pci_resources,
.nr_resources = ARRAY_SIZE(sh7785_pci_resources),
.io_offset = 0,
.mem_offset = 0,
.io_map_base = 0xfe200000,
.serr_irq = evt2irq(0xa00),
.err_irq = evt2irq(0xaa0),
};
struct pci_errors {
unsigned int mask;
const char *str;
} pci_arbiter_errors[] = {
{ SH4_PCIAINT_MBKN, "master broken" },
{ SH4_PCIAINT_TBTO, "target bus time out" },
{ SH4_PCIAINT_MBTO, "master bus time out" },
{ SH4_PCIAINT_TABT, "target abort" },
{ SH4_PCIAINT_MABT, "master abort" },
{ SH4_PCIAINT_RDPE, "read data parity error" },
{ SH4_PCIAINT_WDPE, "write data parity error" },
}, pci_interrupt_errors[] = {
{ SH4_PCIINT_MLCK, "master lock error" },
{ SH4_PCIINT_TABT, "target-target abort" },
{ SH4_PCIINT_TRET, "target retry time out" },
{ SH4_PCIINT_MFDE, "master function disable error" },
{ SH4_PCIINT_PRTY, "address parity error" },
{ SH4_PCIINT_SERR, "SERR" },
{ SH4_PCIINT_TWDP, "data parity error for target write" },
{ SH4_PCIINT_TRDP, "PERR detected for target read" },
{ SH4_PCIINT_MTABT, "target abort for master" },
{ SH4_PCIINT_MMABT, "master abort for master" },
{ SH4_PCIINT_MWPD, "master write data parity error" },
{ SH4_PCIINT_MRPD, "master read data parity error" },
};
static irqreturn_t sh7780_pci_err_irq(int irq, void *dev_id)
{
struct pci_channel *hose = dev_id;
unsigned long addr;
unsigned int status;
unsigned int cmd;
int i;
addr = __raw_readl(hose->reg_base + SH4_PCIALR);
/*
* Handle status errors.
*/
status = __raw_readw(hose->reg_base + PCI_STATUS);
if (status & (PCI_STATUS_PARITY |
PCI_STATUS_DETECTED_PARITY |
PCI_STATUS_SIG_TARGET_ABORT |
PCI_STATUS_REC_TARGET_ABORT |
PCI_STATUS_REC_MASTER_ABORT)) {
cmd = pcibios_handle_status_errors(addr, status, hose);
if (likely(cmd))
__raw_writew(cmd, hose->reg_base + PCI_STATUS);
}
/*
* Handle arbiter errors.
*/
status = __raw_readl(hose->reg_base + SH4_PCIAINT);
for (i = cmd = 0; i < ARRAY_SIZE(pci_arbiter_errors); i++) {
if (status & pci_arbiter_errors[i].mask) {
printk(KERN_DEBUG "PCI: %s, addr=%08lx\n",
pci_arbiter_errors[i].str, addr);
cmd |= pci_arbiter_errors[i].mask;
}
}
__raw_writel(cmd, hose->reg_base + SH4_PCIAINT);
/*
* Handle the remaining PCI errors.
*/
status = __raw_readl(hose->reg_base + SH4_PCIINT);
for (i = cmd = 0; i < ARRAY_SIZE(pci_interrupt_errors); i++) {
if (status & pci_interrupt_errors[i].mask) {
printk(KERN_DEBUG "PCI: %s, addr=%08lx\n",
pci_interrupt_errors[i].str, addr);
cmd |= pci_interrupt_errors[i].mask;
}
}
__raw_writel(cmd, hose->reg_base + SH4_PCIINT);
return IRQ_HANDLED;
}
static irqreturn_t sh7780_pci_serr_irq(int irq, void *dev_id)
{
struct pci_channel *hose = dev_id;
printk(KERN_DEBUG "PCI: system error received: ");
pcibios_report_status(PCI_STATUS_SIG_SYSTEM_ERROR, 1);
pr_cont("\n");
/* Deassert SERR */
__raw_writel(SH4_PCIINTM_SDIM, hose->reg_base + SH4_PCIINTM);
/* Back off the IRQ for awhile */
disable_irq_nosync(irq);
hose->serr_timer.expires = jiffies + HZ;
add_timer(&hose->serr_timer);
return IRQ_HANDLED;
}
static int __init sh7780_pci_setup_irqs(struct pci_channel *hose)
{
int ret;
/* Clear out PCI arbiter IRQs */
__raw_writel(0, hose->reg_base + SH4_PCIAINT);
/* Clear all error conditions */
__raw_writew(PCI_STATUS_DETECTED_PARITY | \
PCI_STATUS_SIG_SYSTEM_ERROR | \
PCI_STATUS_REC_MASTER_ABORT | \
PCI_STATUS_REC_TARGET_ABORT | \
PCI_STATUS_SIG_TARGET_ABORT | \
PCI_STATUS_PARITY, hose->reg_base + PCI_STATUS);
ret = request_irq(hose->serr_irq, sh7780_pci_serr_irq, 0,
"PCI SERR interrupt", hose);
if (unlikely(ret)) {
pr_err("PCI: Failed hooking SERR IRQ\n");
return ret;
}
/*
* The PCI ERR IRQ needs to be IRQF_SHARED since all of the power
* down IRQ vectors are routed through the ERR IRQ vector. We
* only request_irq() once as there is only a single masking
* source for multiple events.
*/
ret = request_irq(hose->err_irq, sh7780_pci_err_irq, IRQF_SHARED,
"PCI ERR interrupt", hose);
if (unlikely(ret)) {
free_irq(hose->serr_irq, hose);
return ret;
}
/* Unmask all of the arbiter IRQs. */
__raw_writel(SH4_PCIAINT_MBKN | SH4_PCIAINT_TBTO | SH4_PCIAINT_MBTO | \
SH4_PCIAINT_TABT | SH4_PCIAINT_MABT | SH4_PCIAINT_RDPE | \
SH4_PCIAINT_WDPE, hose->reg_base + SH4_PCIAINTM);
/* Unmask all of the PCI IRQs */
__raw_writel(SH4_PCIINTM_TTADIM | SH4_PCIINTM_TMTOIM | \
SH4_PCIINTM_MDEIM | SH4_PCIINTM_APEDIM | \
SH4_PCIINTM_SDIM | SH4_PCIINTM_DPEITWM | \
SH4_PCIINTM_PEDITRM | SH4_PCIINTM_TADIMM | \
SH4_PCIINTM_MADIMM | SH4_PCIINTM_MWPDIM | \
SH4_PCIINTM_MRDPEIM, hose->reg_base + SH4_PCIINTM);
return ret;
}
static inline void __init sh7780_pci_teardown_irqs(struct pci_channel *hose)
{
free_irq(hose->err_irq, hose);
free_irq(hose->serr_irq, hose);
}
static void __init sh7780_pci66_init(struct pci_channel *hose)
{
unsigned int tmp;
if (!pci_is_66mhz_capable(hose, 0, 0))
return;
/* Enable register access */
tmp = __raw_readl(hose->reg_base + SH4_PCICR);
tmp |= SH4_PCICR_PREFIX;
__raw_writel(tmp, hose->reg_base + SH4_PCICR);
/* Enable 66MHz operation */
tmp = __raw_readw(hose->reg_base + PCI_STATUS);
tmp |= PCI_STATUS_66MHZ;
__raw_writew(tmp, hose->reg_base + PCI_STATUS);
/* Done */
tmp = __raw_readl(hose->reg_base + SH4_PCICR);
tmp |= SH4_PCICR_PREFIX | SH4_PCICR_CFIN;
__raw_writel(tmp, hose->reg_base + SH4_PCICR);
}
static int __init sh7780_pci_init(void)
{
struct pci_channel *chan = &sh7780_pci_controller;
phys_addr_t memphys;
size_t memsize;
unsigned int id;
const char *type;
int ret, i;
pr_notice("PCI: Starting initialization.\n");
chan->reg_base = 0xfe040000;
/* Enable CPU access to the PCIC registers. */
__raw_writel(PCIECR_ENBL, PCIECR);
/* Reset */
__raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_PRST | PCICR_ENDIANNESS,
chan->reg_base + SH4_PCICR);
/*
* Wait for it to come back up. The spec says to allow for up to
* 1 second after toggling the reset pin, but in practice 100ms
* is more than enough.
*/
mdelay(100);
id = __raw_readw(chan->reg_base + PCI_VENDOR_ID);
if (id != PCI_VENDOR_ID_RENESAS) {
pr_err("PCI: Unknown vendor ID 0x%04x.\n", id);
return -ENODEV;
}
id = __raw_readw(chan->reg_base + PCI_DEVICE_ID);
type = (id == PCI_DEVICE_ID_RENESAS_SH7763) ? "SH7763" :
(id == PCI_DEVICE_ID_RENESAS_SH7780) ? "SH7780" :
(id == PCI_DEVICE_ID_RENESAS_SH7781) ? "SH7781" :
(id == PCI_DEVICE_ID_RENESAS_SH7785) ? "SH7785" :
NULL;
if (unlikely(!type)) {
pr_err("PCI: Found an unsupported Renesas host controller, device id 0x%04x.\n",
id);
return -EINVAL;
}
pr_notice("PCI: Found a Renesas %s host controller, revision %d.\n",
type, __raw_readb(chan->reg_base + PCI_REVISION_ID));
/*
* Now throw it in to register initialization mode and
* start the real work.
*/
__raw_writel(SH4_PCICR_PREFIX | PCICR_ENDIANNESS,
chan->reg_base + SH4_PCICR);
memphys = __pa(memory_start);
memsize = roundup_pow_of_two(memory_end - memory_start);
/*
* If there's more than 512MB of memory, we need to roll over to
* LAR1/LSR1.
*/
if (memsize > SZ_512M) {
__raw_writel(memphys + SZ_512M, chan->reg_base + SH4_PCILAR1);
__raw_writel((((memsize - SZ_512M) - SZ_1M) & 0x1ff00000) | 1,
chan->reg_base + SH4_PCILSR1);
memsize = SZ_512M;
} else {
/*
* Otherwise just zero it out and disable it.
*/
__raw_writel(0, chan->reg_base + SH4_PCILAR1);
__raw_writel(0, chan->reg_base + SH4_PCILSR1);
}
/*
* LAR0/LSR0 covers up to the first 512MB, which is enough to
* cover all of lowmem on most platforms.
*/
__raw_writel(memphys, chan->reg_base + SH4_PCILAR0);
__raw_writel(((memsize - SZ_1M) & 0x1ff00000) | 1,
chan->reg_base + SH4_PCILSR0);
/*
* Hook up the ERR and SERR IRQs.
*/
ret = sh7780_pci_setup_irqs(chan);
if (unlikely(ret))
return ret;
/*
* Disable the cache snoop controller for non-coherent DMA.
*/
__raw_writel(0, chan->reg_base + SH7780_PCICSCR0);
__raw_writel(0, chan->reg_base + SH7780_PCICSAR0);
__raw_writel(0, chan->reg_base + SH7780_PCICSCR1);
__raw_writel(0, chan->reg_base + SH7780_PCICSAR1);
/*
* Setup the memory BARs
*/
for (i = 1; i < chan->nr_resources; i++) {
struct resource *res = chan->resources + i;
resource_size_t size;
if (unlikely(res->flags & IORESOURCE_IO))
continue;
/*
* Make sure we're in the right physical addressing mode
* for dealing with the resource.
*/
if ((res->flags & IORESOURCE_MEM_32BIT) && __in_29bit_mode()) {
chan->nr_resources--;
continue;
}
size = resource_size(res);
/*
* The MBMR mask is calculated in units of 256kB, which
* keeps things pretty simple.
*/
__raw_writel(((roundup_pow_of_two(size) / SZ_256K) - 1) << 18,
chan->reg_base + SH7780_PCIMBMR(i - 1));
__raw_writel(res->start, chan->reg_base + SH7780_PCIMBR(i - 1));
}
/*
* And I/O.
*/
__raw_writel(0, chan->reg_base + PCI_BASE_ADDRESS_0);
__raw_writel(0, chan->reg_base + SH7780_PCIIOBR);
__raw_writel(0, chan->reg_base + SH7780_PCIIOBMR);
__raw_writew(PCI_COMMAND_SERR | PCI_COMMAND_WAIT | \
PCI_COMMAND_PARITY | PCI_COMMAND_MASTER | \
PCI_COMMAND_MEMORY, chan->reg_base + PCI_COMMAND);
/*
* Initialization mode complete, release the control register and
* enable round robin mode to stop device overruns/starvation.
*/
__raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_CFIN | SH4_PCICR_FTO |
PCICR_ENDIANNESS,
chan->reg_base + SH4_PCICR);
ret = register_pci_controller(chan);
if (unlikely(ret))
goto err;
sh7780_pci66_init(chan);
pr_notice("PCI: Running at %dMHz.\n",
(__raw_readw(chan->reg_base + PCI_STATUS) & PCI_STATUS_66MHZ)
? 66 : 33);
return 0;
err:
sh7780_pci_teardown_irqs(chan);
return ret;
}
arch_initcall(sh7780_pci_init);