aspeed: add support for the SMC segment registers

The SMC controller on the Aspeed SoC has a set of registers to
configure the mapping of each flash module in the SoC address
space. Writing to these registers triggers a remap of the memory
region and the spec requires a certain number of checks before doing
so.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Message-id: 1474977462-28032-7-git-send-email-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Cédric Le Goater 2016-10-17 19:22:17 +01:00 committed by Peter Maydell
parent 2da95fd88b
commit a03cb1daf1

View file

@ -79,10 +79,10 @@
/* CEx Segment Address Register */
#define R_SEG_ADDR0 (0x30 / 4)
#define SEG_SIZE_SHIFT 24 /* 8MB units */
#define SEG_SIZE_MASK 0x7f
#define SEG_END_SHIFT 24 /* 8MB units */
#define SEG_END_MASK 0xff
#define SEG_START_SHIFT 16 /* address bit [A29-A23] */
#define SEG_START_MASK 0x7f
#define SEG_START_MASK 0xff
#define R_SEG_ADDR1 (0x34 / 4)
#define R_SEG_ADDR2 (0x38 / 4)
#define R_SEG_ADDR3 (0x3C / 4)
@ -135,8 +135,7 @@
/*
* Default segments mapping addresses and size for each slave per
* controller. These can be changed when board is initialized with the
* Segment Address Registers but they don't seem do be used on the
* field.
* Segment Address Registers.
*/
static const AspeedSegments aspeed_segments_legacy[] = {
{ 0x10000000, 32 * 1024 * 1024 },
@ -191,6 +190,118 @@ static const AspeedSMCController controllers[] = {
ASPEED_SOC_SPI2_FLASH_BASE, 0x8000000 },
};
/*
* The Segment Register uses a 8MB unit to encode the start address
* and the end address of the mapping window of a flash SPI slave :
*
* | byte 1 | byte 2 | byte 3 | byte 4 |
* +--------+--------+--------+--------+
* | end | start | 0 | 0 |
*
*/
static inline uint32_t aspeed_smc_segment_to_reg(const AspeedSegments *seg)
{
uint32_t reg = 0;
reg |= ((seg->addr >> 23) & SEG_START_MASK) << SEG_START_SHIFT;
reg |= (((seg->addr + seg->size) >> 23) & SEG_END_MASK) << SEG_END_SHIFT;
return reg;
}
static inline void aspeed_smc_reg_to_segment(uint32_t reg, AspeedSegments *seg)
{
seg->addr = ((reg >> SEG_START_SHIFT) & SEG_START_MASK) << 23;
seg->size = (((reg >> SEG_END_SHIFT) & SEG_END_MASK) << 23) - seg->addr;
}
static bool aspeed_smc_flash_overlap(const AspeedSMCState *s,
const AspeedSegments *new,
int cs)
{
AspeedSegments seg;
int i;
for (i = 0; i < s->ctrl->max_slaves; i++) {
if (i == cs) {
continue;
}
aspeed_smc_reg_to_segment(s->regs[R_SEG_ADDR0 + i], &seg);
if (new->addr + new->size > seg.addr &&
new->addr < seg.addr + seg.size) {
qemu_log_mask(LOG_GUEST_ERROR, "%s: new segment CS%d [ 0x%"
HWADDR_PRIx" - 0x%"HWADDR_PRIx" ] overlaps with "
"CS%d [ 0x%"HWADDR_PRIx" - 0x%"HWADDR_PRIx" ]\n",
s->ctrl->name, cs, new->addr, new->addr + new->size,
i, seg.addr, seg.addr + seg.size);
return true;
}
}
return false;
}
static void aspeed_smc_flash_set_segment(AspeedSMCState *s, int cs,
uint64_t new)
{
AspeedSMCFlash *fl = &s->flashes[cs];
AspeedSegments seg;
aspeed_smc_reg_to_segment(new, &seg);
/* The start address of CS0 is read-only */
if (cs == 0 && seg.addr != s->ctrl->flash_window_base) {
qemu_log_mask(LOG_GUEST_ERROR,
"%s: Tried to change CS0 start address to 0x%"
HWADDR_PRIx "\n", s->ctrl->name, seg.addr);
return;
}
/*
* The end address of the AST2500 spi controllers is also
* read-only.
*/
if ((s->ctrl->segments == aspeed_segments_ast2500_spi1 ||
s->ctrl->segments == aspeed_segments_ast2500_spi2) &&
cs == s->ctrl->max_slaves &&
seg.addr + seg.size != s->ctrl->segments[cs].addr +
s->ctrl->segments[cs].size) {
qemu_log_mask(LOG_GUEST_ERROR,
"%s: Tried to change CS%d end address to 0x%"
HWADDR_PRIx "\n", s->ctrl->name, cs, seg.addr);
return;
}
/* Keep the segment in the overall flash window */
if (seg.addr + seg.size <= s->ctrl->flash_window_base ||
seg.addr > s->ctrl->flash_window_base + s->ctrl->flash_window_size) {
qemu_log_mask(LOG_GUEST_ERROR, "%s: new segment for CS%d is invalid : "
"[ 0x%"HWADDR_PRIx" - 0x%"HWADDR_PRIx" ]\n",
s->ctrl->name, cs, seg.addr, seg.addr + seg.size);
return;
}
/* Check start address vs. alignment */
if (seg.addr % seg.size) {
qemu_log_mask(LOG_GUEST_ERROR, "%s: new segment for CS%d is not "
"aligned : [ 0x%"HWADDR_PRIx" - 0x%"HWADDR_PRIx" ]\n",
s->ctrl->name, cs, seg.addr, seg.addr + seg.size);
}
/* And segments should not overlap */
if (aspeed_smc_flash_overlap(s, &seg, cs)) {
return;
}
/* All should be fine now to move the region */
memory_region_transaction_begin();
memory_region_set_size(&fl->mmio, seg.size);
memory_region_set_address(&fl->mmio, seg.addr - s->ctrl->flash_window_base);
memory_region_set_enabled(&fl->mmio, true);
memory_region_transaction_commit();
s->regs[R_SEG_ADDR0 + cs] = new;
}
static uint64_t aspeed_smc_flash_default_read(void *opaque, hwaddr addr,
unsigned size)
{
@ -314,6 +425,12 @@ static void aspeed_smc_reset(DeviceState *d)
s->regs[s->r_ctrl0 + i] |= CTRL_CE_STOP_ACTIVE;
}
/* setup default segment register values for all */
for (i = 0; i < s->ctrl->max_slaves; ++i) {
s->regs[R_SEG_ADDR0 + i] =
aspeed_smc_segment_to_reg(&s->ctrl->segments[i]);
}
aspeed_smc_update_cs(s);
}
@ -334,6 +451,7 @@ static uint64_t aspeed_smc_read(void *opaque, hwaddr addr, unsigned int size)
addr == s->r_timings ||
addr == s->r_ce_ctrl ||
addr == R_INTR_CTRL ||
(addr >= R_SEG_ADDR0 && addr < R_SEG_ADDR0 + s->ctrl->max_slaves) ||
(addr >= s->r_ctrl0 && addr < s->r_ctrl0 + s->num_cs)) {
return s->regs[addr];
} else {
@ -365,6 +483,13 @@ static void aspeed_smc_write(void *opaque, hwaddr addr, uint64_t data,
} else if (addr >= s->r_ctrl0 && addr < s->r_ctrl0 + s->num_cs) {
s->regs[addr] = value;
aspeed_smc_update_cs(s);
} else if (addr >= R_SEG_ADDR0 &&
addr < R_SEG_ADDR0 + s->ctrl->max_slaves) {
int cs = addr - R_SEG_ADDR0;
if (value != s->regs[R_SEG_ADDR0 + cs]) {
aspeed_smc_flash_set_segment(s, cs, value);
}
} else {
qemu_log_mask(LOG_UNIMP, "%s: not implemented: 0x%" HWADDR_PRIx "\n",
__func__, addr);