/* memctrlr.c: Driver for UltraSPARC-III memory controller.
*
* Copyright (C) 2001, 2007 David S. Miller (davem@davemloft.net)
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/string.h>
#include <linux/sched.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <asm/spitfire.h>
#include <asm/chmctrl.h>
#include <asm/cpudata.h>
#include <asm/oplib.h>
#include <asm/prom.h>
#include <asm/io.h>
#define CHMCTRL_NDGRPS 2
#define CHMCTRL_NDIMMS 4
#define DIMMS_PER_MC (CHMCTRL_NDGRPS * CHMCTRL_NDIMMS)
/* OBP memory-layout property format. */
struct obp_map {
unsigned char dimm_map[144];
unsigned char pin_map[576];
};
#define DIMM_LABEL_SZ 8
struct obp_mem_layout {
/* One max 8-byte string label per DIMM. Usually
* this matches the label on the motherboard where
* that DIMM resides.
*/
char dimm_labels[DIMMS_PER_MC][DIMM_LABEL_SZ];
/* If symmetric use map[0], else it is
* asymmetric and map[1] should be used.
*/
char symmetric;
struct obp_map map[2];
};
#define CHMCTRL_NBANKS 4
struct bank_info {
struct mctrl_info *mp;
int bank_id;
u64 raw_reg;
int valid;
int uk;
int um;
int lk;
int lm;
int interleave;
unsigned long base;
unsigned long size;
};
struct mctrl_info {
struct list_head list;
int portid;
struct obp_mem_layout layout_prop;
int layout_size;
void __iomem *regs;
u64 timing_control1;
u64 timing_control2;
u64 timing_control3;
u64 timing_control4;
u64 memaddr_control;
struct bank_info logical_banks[CHMCTRL_NBANKS];
};
static LIST_HEAD(mctrl_list);
/* Does BANK decode PHYS_ADDR? */
static int bank_match(struct bank_info *bp, unsigned long phys_addr)
{
unsigned long upper_bits = (phys_addr & PA_UPPER_BITS) >> PA_UPPER_BITS_SHIFT;
unsigned long lower_bits = (phys_addr & PA_LOWER_BITS) >> PA_LOWER_BITS_SHIFT;
/* Bank must be enabled to match. */
if (bp->valid == 0)
return 0;
/* Would BANK match upper bits? */
upper_bits ^= bp->um; /* What bits are different? */
upper_bits = ~upper_bits; /* Invert. */
upper_bits |= bp->uk; /* What bits don't matter for matching? */
upper_bits = ~upper_bits; /* Invert. */
if (upper_bits)
return 0;
/* Would BANK match lower bits? */
lower_bits ^= bp->lm; /* What bits are different? */
lower_bits = ~lower_bits; /* Invert. */
lower_bits |= bp->lk; /* What bits don't matter for matching? */
lower_bits = ~lower_bits; /* Invert. */
if (lower_bits)
return 0;
/* I always knew you'd be the one. */
return 1;
}
/* Given PHYS_ADDR, search memory controller banks for a match. */
static struct bank_info *find_bank(unsigned long phys_addr)
{
struct list_head *mctrl_head = &mctrl_list;
struct list_head *mctrl_entry = mctrl_head->next;
for (;;) {
struct mctrl_info *mp =
list_entry(mctrl_entry, struct mctrl_info, list);
int bank_no;
if (mctrl_entry == mctrl_head)
break;
mctrl_entry = mctrl_entry->next;
for (bank_no = 0; bank_no < CHMCTRL_NBANKS; bank_no++) {
struct bank_info *bp;
bp = &mp->logical_banks[bank_no];
if (bank_match(bp, phys_addr))
return bp;
}
}
return NULL;
}
/* This is the main purpose of this driver. */
#define SYNDROME_MIN -1
#define SYNDROME_MAX 144
int chmc_getunumber(int syndrome_code,
unsigned long phys_addr,
char *buf, int buflen)
{
struct bank_info *bp;
struct obp_mem_layout *prop;
int bank_in_controller, first_dimm;
bp = find_bank(phys_addr);
if (bp == NULL ||
syndrome_code < SYNDROME_MIN ||
syndrome_code > SYNDROME_MAX) {
buf[0] = '?';
buf[1] = '?';
buf[2] = '?';
buf[3] = '\0';
return 0;
}
prop = &bp->mp->layout_prop;
bank_in_controller = bp->bank_id & (CHMCTRL_NBANKS - 1);
first_dimm = (bank_in_controller & (CHMCTRL_NDGRPS - 1));
first_dimm *= CHMCTRL_NDIMMS;
if (syndrome_code != SYNDROME_MIN) {
struct obp_map *map;
int qword, where_in_line, where, map_index, map_offset;
unsigned int map_val;
/* Yaay, single bit error so we can figure out
* the exact dimm.
*/
if (prop->symmetric)
map = &prop->map[0];
else
map = &prop->map[1];
/* Covert syndrome code into the way the bits are
* positioned on the bus.
*/
if (syndrome_code < 144 - 16)
syndrome_code += 16;
else if (syndrome_code < 144)
syndrome_code -= (144 - 7);
else if (syndrome_code < (144 + 3))
syndrome_code -= (144 + 3 - 4);
else
syndrome_code -= 144 + 3;
/* All this magic has to do with how a cache line
* comes over the wire on Safari. A 64-bit line
* comes over in 4 quadword cycles, each of which
* transmit ECC/MTAG info as well as the actual
* data. 144 bits per quadword, 576 total.
*/
#define LINE_SIZE 64
#define LINE_ADDR_MSK (LINE_SIZE - 1)
#define QW_PER_LINE 4
#define QW_BYTES (LINE_SIZE / QW_PER_LINE)
#define QW_BITS 144
#define LAST_BIT (576 - 1)
qword = (phys_addr & LINE_ADDR_MSK) / QW_BYTES;
where_in_line = ((3 - qword) * QW_BITS) + syndrome_code;
where = (LAST_BIT - where_in_line);
map_index = where >> 2;
map_offset = where & 0x3;
map_val = map->dimm_map[map_index];
map_val = ((map_val >> ((3 - map_offset) << 1)) & (2 - 1));
sprintf(buf, "%s, pin %3d",
prop->dimm_labels[first_dimm + map_val],
map->pin_map[where_in_line]);
} else {
int dimm;
/* Multi-bit error, we just dump out all the
* dimm labels associated with this bank.
*/
for (dimm = 0; dimm < CHMCTRL_NDIMMS; dimm++) {
sprintf(buf, "%s ",
prop->dimm_labels[first_dimm + dimm]);
buf += strlen(buf);
}
}
return 0;
}
/* Accessing the registers is slightly complicated. If you want
* to get at the memory controller which is on the same processor
* the code is executing, you must use special ASI load/store else
* you go through the global mapping.
*/
static u64 read_mcreg(struct mctrl_info *mp, unsigned long offset)
{
unsigned long ret, this_cpu;
preempt_disable();
this_cpu = real_hard_smp_processor_id();
if (mp->portid == this_cpu) {
__asm__ __volatile__("ldxa [%1] %2, %0"
: "=r" (ret)
: "r" (offset), "i" (ASI_MCU_CTRL_REG));
} else {
__asm__ __volatile__("ldxa [%1] %2, %0"
: "=r" (ret)
: "r" (mp->regs + offset),
"i" (ASI_PHYS_BYPASS_EC_E));
}
preempt_enable();
return ret;
}
#if 0 /* currently unused */
static void write_mcreg(struct mctrl_info *mp, unsigned long offset, u64 val)
{
if (mp->portid == smp_processor_id()) {
__asm__ __volatile__("stxa %0, [%1] %2"
: : "r" (val),
"r" (offset), "i" (ASI_MCU_CTRL_REG));
} else {
__asm__ __volatile__("ldxa %0, [%1] %2"
: : "r" (val),
"r" (mp->regs + offset),
"i" (ASI_PHYS_BYPASS_EC_E));
}
}
#endif
static void interpret_one_decode_reg(struct mctrl_info *mp, int which_bank, u64 val)
{
struct bank_info *p = &mp->logical_banks[which_bank];
p->mp = mp;
p->bank_id = (CHMCTRL_NBANKS * mp->portid) + which_bank;
p->raw_reg = val;
p->valid = (val & MEM_DECODE_VALID) >> MEM_DECODE_VALID_SHIFT;
p->uk = (val & MEM_DECODE_UK) >> MEM_DECODE_UK_SHIFT;
p->um = (val & MEM_DECODE_UM) >> MEM_DECODE_UM_SHIFT;
p->lk = (val & MEM_DECODE_LK) >> MEM_DECODE_LK_SHIFT;
p->lm = (val & MEM_DECODE_LM) >> MEM_DECODE_LM_SHIFT;
p->base = (p->um);
p->base &= ~(p->uk);
p->base <<= PA_UPPER_BITS_SHIFT;
switch(p->lk) {
case 0xf:
default:
p->interleave = 1;
break;
case 0xe:
p->interleave = 2;
break;
case 0xc:
p->interleave = 4;
break;
case 0x8:
p->interleave = 8;
break;
case 0x0:
p->interleave = 16;
break;
};
/* UK[10] is reserved, and UK[11] is not set for the SDRAM
* bank size definition.
*/
p->size = (((unsigned long)p->uk &
((1UL << 10UL) - 1UL)) + 1UL) << PA_UPPER_BITS_SHIFT;
p->size /= p->interleave;
}
static void fetch_decode_regs(struct mctrl_info *mp)
{
if (mp->layout_size == 0)
return;
interpret_one_decode_reg(mp, 0,
read_mcreg(mp, CHMCTRL_DECODE1));
interpret_one_decode_reg(mp, 1,
read_mcreg(mp, CHMCTRL_DECODE2));
interpret_one_decode_reg(mp, 2,
read_mcreg(mp, CHMCTRL_DECODE3));
interpret_one_decode_reg(mp, 3,
read_mcreg(mp, CHMCTRL_DECODE4));
}
static int init_one_mctrl(struct device_node *dp)
{
struct mctrl_info *mp = kzalloc(sizeof(*mp), GFP_KERNEL);
int portid = of_getintprop_default(dp, "portid", -1);
const struct linux_prom64_registers *regs;
const void *pval;
int len;
if (!mp)
return -1;
if (portid == -1)
goto fail;
mp->portid = portid;
pval = of_get_property(dp, "memory-layout", &len);
mp->layout_size = len;
if (!pval)
mp->layout_size = 0;
else {
if (mp->layout_size > sizeof(mp->layout_prop))
goto fail;
memcpy(&mp->layout_prop, pval, len);
}
regs = of_get_property(dp, "reg", NULL);
if (!regs || regs->reg_size != 0x48)
goto fail;
mp->regs = ioremap(regs->phys_addr, regs->reg_size);
if (mp->regs == NULL)
goto fail;
if (mp->layout_size != 0UL) {
mp->timing_control1 = read_mcreg(mp, CHMCTRL_TCTRL1);
mp->timing_control2 = read_mcreg(mp, CHMCTRL_TCTRL2);
mp->timing_control3 = read_mcreg(mp, CHMCTRL_TCTRL3);
mp->timing_control4 = read_mcreg(mp, CHMCTRL_TCTRL4);
mp->memaddr_control = read_mcreg(mp, CHMCTRL_MACTRL);
}
fetch_decode_regs(mp);
list_add(&mp->list, &mctrl_list);
/* Report the device. */
printk(KERN_INFO "%s: US3 memory controller at %p [%s]\n",
dp->full_name,
mp->regs, (mp->layout_size ? "ACTIVE" : "INACTIVE"));
return 0;
fail:
if (mp) {
if (mp->regs != NULL)
iounmap(mp->regs);
kfree(mp);
}
return -1;
}
static int __init chmc_init(void)
{
struct device_node *dp;
/* This driver is only for cheetah platforms. */
if (tlb_type != cheetah && tlb_type != cheetah_plus)
return -ENODEV;
for_each_node_by_name(dp, "memory-controller")
init_one_mctrl(dp);
for_each_node_by_name(dp, "mc-us3")
init_one_mctrl(dp);
return 0;
}
static void __exit chmc_cleanup(void)
{
struct list_head *head = &mctrl_list;
struct list_head *tmp = head->next;
for (;;) {
struct mctrl_info *p =
list_entry(tmp, struct mctrl_info, list);
if (tmp == head)
break;
tmp = tmp->next;
list_del(&p->list);
iounmap(p->regs);
kfree(p);
}
}
module_init(chmc_init);
module_exit(chmc_cleanup);
