u-boot/arch/x86/cpu/quark/dram.c
Bin Meng c6d4705f41 x86: quark: Configure MTRR to enable cache
Quark SoC does not support MSR MTRRs. Fixed and variable range MTRRs
are accessed indirectly via the message port and not the traditional
MSR mechanism. Only UC, WT and WB cache types are supported.

We configure all the fixed range MTRRs with common values (VGA RAM
as UC, others as WB) and 3 variable range MTRRs for ROM/eSRAM/RAM as
WB, which significantly improves the boot time performance.

With this commit, it takes only 2 seconds for U-Boot to boot to shell
on Intel Galileo board. Previously it took about 6 seconds.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
2015-09-16 19:53:53 -06:00

144 lines
4.1 KiB
C

/*
* Copyright (C) 2015, Bin Meng <bmeng.cn@gmail.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <errno.h>
#include <fdtdec.h>
#include <asm/mtrr.h>
#include <asm/post.h>
#include <asm/arch/mrc.h>
#include <asm/arch/msg_port.h>
#include <asm/arch/quark.h>
DECLARE_GLOBAL_DATA_PTR;
static int mrc_configure_params(struct mrc_params *mrc_params)
{
const void *blob = gd->fdt_blob;
int node;
int mrc_flags;
node = fdtdec_next_compatible(blob, 0, COMPAT_INTEL_QRK_MRC);
if (node < 0) {
debug("%s: Cannot find MRC node\n", __func__);
return -EINVAL;
}
/*
* TODO:
*
* We need support fast boot (MRC cache) in the future.
*
* Set boot mode to cold boot for now
*/
mrc_params->boot_mode = BM_COLD;
/*
* TODO:
*
* We need determine ECC by pin strap state
*
* Disable ECC by default for now
*/
mrc_params->ecc_enables = 0;
mrc_flags = fdtdec_get_int(blob, node, "flags", 0);
if (mrc_flags & MRC_FLAG_SCRAMBLE_EN)
mrc_params->scrambling_enables = 1;
else
mrc_params->scrambling_enables = 0;
mrc_params->dram_width = fdtdec_get_int(blob, node, "dram-width", 0);
mrc_params->ddr_speed = fdtdec_get_int(blob, node, "dram-speed", 0);
mrc_params->ddr_type = fdtdec_get_int(blob, node, "dram-type", 0);
mrc_params->rank_enables = fdtdec_get_int(blob, node, "rank-mask", 0);
mrc_params->channel_enables = fdtdec_get_int(blob, node,
"chan-mask", 0);
mrc_params->channel_width = fdtdec_get_int(blob, node,
"chan-width", 0);
mrc_params->address_mode = fdtdec_get_int(blob, node, "addr-mode", 0);
mrc_params->refresh_rate = fdtdec_get_int(blob, node,
"refresh-rate", 0);
mrc_params->sr_temp_range = fdtdec_get_int(blob, node,
"sr-temp-range", 0);
mrc_params->ron_value = fdtdec_get_int(blob, node,
"ron-value", 0);
mrc_params->rtt_nom_value = fdtdec_get_int(blob, node,
"rtt-nom-value", 0);
mrc_params->rd_odt_value = fdtdec_get_int(blob, node,
"rd-odt-value", 0);
mrc_params->params.density = fdtdec_get_int(blob, node,
"dram-density", 0);
mrc_params->params.cl = fdtdec_get_int(blob, node, "dram-cl", 0);
mrc_params->params.ras = fdtdec_get_int(blob, node, "dram-ras", 0);
mrc_params->params.wtr = fdtdec_get_int(blob, node, "dram-wtr", 0);
mrc_params->params.rrd = fdtdec_get_int(blob, node, "dram-rrd", 0);
mrc_params->params.faw = fdtdec_get_int(blob, node, "dram-faw", 0);
debug("MRC dram_width %d\n", mrc_params->dram_width);
debug("MRC rank_enables %d\n", mrc_params->rank_enables);
debug("MRC ddr_speed %d\n", mrc_params->ddr_speed);
debug("MRC flags: %s\n",
(mrc_params->scrambling_enables) ? "SCRAMBLE_EN" : "");
debug("MRC density=%d tCL=%d tRAS=%d tWTR=%d tRRD=%d tFAW=%d\n",
mrc_params->params.density, mrc_params->params.cl,
mrc_params->params.ras, mrc_params->params.wtr,
mrc_params->params.rrd, mrc_params->params.faw);
return 0;
}
int dram_init(void)
{
struct mrc_params mrc_params;
int ret;
memset(&mrc_params, 0, sizeof(struct mrc_params));
ret = mrc_configure_params(&mrc_params);
if (ret)
return ret;
/* Set up the DRAM by calling the memory reference code */
mrc_init(&mrc_params);
if (mrc_params.status)
return -EIO;
gd->ram_size = mrc_params.mem_size;
post_code(POST_DRAM);
/* variable range MTRR#2: RAM area */
disable_caches();
msg_port_write(MSG_PORT_HOST_BRIDGE, MTRR_VAR_PHYBASE(MTRR_VAR_RAM),
0 | MTRR_TYPE_WRBACK);
msg_port_write(MSG_PORT_HOST_BRIDGE, MTRR_VAR_PHYMASK(MTRR_VAR_RAM),
(~(gd->ram_size - 1)) | MTRR_PHYS_MASK_VALID);
enable_caches();
return 0;
}
void dram_init_banksize(void)
{
gd->bd->bi_dram[0].start = 0;
gd->bd->bi_dram[0].size = gd->ram_size;
}
/*
* This function looks for the highest region of memory lower than 4GB which
* has enough space for U-Boot where U-Boot is aligned on a page boundary.
* It overrides the default implementation found elsewhere which simply
* picks the end of ram, wherever that may be. The location of the stack,
* the relocation address, and how far U-Boot is moved by relocation are
* set in the global data structure.
*/
ulong board_get_usable_ram_top(ulong total_size)
{
return gd->ram_size;
}