u-boot/arch/arm/cpu/armv7/sunxi/dram_sun6i.c
Siarhei Siamashka c3d2b963c6 sunxi: Fix buggy sun6i/sun8i DRAM size detection logic
After reboot, reset or even short power off, DRAM typically retains
the old stale data for some period of time (for this type of memory,
the bits of data are stored in slowly discharging capacitors).

The current sun6i/sun8i DRAM size detection logic, which is
inherited from the Allwinner code, relies on using a large magic
signature with the hope that it is unique enough and unlikely to
ever accidentally match this leftover garbage data in RAM. But
this approach is inherently unsafe, as can be demonstrated using
the following test program:

/***** A testcase for reproducing the problem ******/

void main(int argc, char *argv[])
{
    size_t size, i;
    uint32_t *buf;
    /* Allocate the buffer */
    if (argc < 2 || !(size = (size_t)atoi(argv[1]) * 1048576) ||
                    !(buf = malloc(size))) {
        printf("Need buffer size in MiB as a cmdline argument\n");
        exit(1);
    }
    /* Fill it with the Allwinner DRAM "magic" values */
    for (i = 0; i < size / 4; i++)
        buf[i] = 0xaa55aa55 + ((uintptr_t)&buf[i] / 4) % 64;
    /* Try to reboot */
    system("reboot");
    /* And wait */
    for (;;) {}
}
/***************************************************/

If this test program is run on the device (giving it a large
chunk of memory), then the DRAM size detection logic in u-boot
gets confused after reboot and fails to initialize DRAM properly.

A better approach is not to rely on luck and abstain from making
any assumptions about the properties of the leftover garbage
data in RAM. Instead just use a more reliable code for testing
whether two different addresses refer to the same memory location.

Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2015-01-14 14:56:37 +01:00

412 lines
13 KiB
C

/*
* Sun6i platform dram controller init.
*
* (C) Copyright 2007-2012
* Allwinner Technology Co., Ltd. <www.allwinnertech.com>
* Berg Xing <bergxing@allwinnertech.com>
* Tom Cubie <tangliang@allwinnertech.com>
*
* (C) Copyright 2014 Hans de Goede <hdegoede@redhat.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <errno.h>
#include <asm/io.h>
#include <asm/arch/clock.h>
#include <asm/arch/dram.h>
#include <asm/arch/prcm.h>
#define DRAM_CLK (CONFIG_DRAM_CLK * 1000000)
struct dram_sun6i_para {
u8 bus_width;
u8 chan;
u8 rank;
u8 rows;
u16 page_size;
};
static void mctl_sys_init(void)
{
struct sunxi_ccm_reg * const ccm =
(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
const int dram_clk_div = 2;
clock_set_pll5(DRAM_CLK * dram_clk_div, false);
clrsetbits_le32(&ccm->dram_clk_cfg, CCM_DRAMCLK_CFG_DIV0_MASK,
CCM_DRAMCLK_CFG_DIV0(dram_clk_div) | CCM_DRAMCLK_CFG_RST |
CCM_DRAMCLK_CFG_UPD);
mctl_await_completion(&ccm->dram_clk_cfg, CCM_DRAMCLK_CFG_UPD, 0);
writel(MDFS_CLK_DEFAULT, &ccm->mdfs_clk_cfg);
/* deassert mctl reset */
setbits_le32(&ccm->ahb_reset0_cfg, 1 << AHB_RESET_OFFSET_MCTL);
/* enable mctl clock */
setbits_le32(&ccm->ahb_gate0, 1 << AHB_GATE_OFFSET_MCTL);
}
static void mctl_dll_init(int ch_index, struct dram_sun6i_para *para)
{
struct sunxi_mctl_phy_reg *mctl_phy;
if (ch_index == 0)
mctl_phy = (struct sunxi_mctl_phy_reg *)SUNXI_DRAM_PHY0_BASE;
else
mctl_phy = (struct sunxi_mctl_phy_reg *)SUNXI_DRAM_PHY1_BASE;
/* disable + reset dlls */
writel(MCTL_DLLCR_DISABLE, &mctl_phy->acdllcr);
writel(MCTL_DLLCR_DISABLE, &mctl_phy->dx0dllcr);
writel(MCTL_DLLCR_DISABLE, &mctl_phy->dx1dllcr);
if (para->bus_width == 32) {
writel(MCTL_DLLCR_DISABLE, &mctl_phy->dx2dllcr);
writel(MCTL_DLLCR_DISABLE, &mctl_phy->dx3dllcr);
}
udelay(2);
/* enable + reset dlls */
writel(0, &mctl_phy->acdllcr);
writel(0, &mctl_phy->dx0dllcr);
writel(0, &mctl_phy->dx1dllcr);
if (para->bus_width == 32) {
writel(0, &mctl_phy->dx2dllcr);
writel(0, &mctl_phy->dx3dllcr);
}
udelay(22);
/* enable and release reset of dlls */
writel(MCTL_DLLCR_NRESET, &mctl_phy->acdllcr);
writel(MCTL_DLLCR_NRESET, &mctl_phy->dx0dllcr);
writel(MCTL_DLLCR_NRESET, &mctl_phy->dx1dllcr);
if (para->bus_width == 32) {
writel(MCTL_DLLCR_NRESET, &mctl_phy->dx2dllcr);
writel(MCTL_DLLCR_NRESET, &mctl_phy->dx3dllcr);
}
udelay(22);
}
static bool mctl_rank_detect(u32 *gsr0, int rank)
{
const u32 done = MCTL_DX_GSR0_RANK0_TRAIN_DONE << rank;
const u32 err = MCTL_DX_GSR0_RANK0_TRAIN_ERR << rank;
mctl_await_completion(gsr0, done, done);
mctl_await_completion(gsr0 + 0x10, done, done);
return !(readl(gsr0) & err) && !(readl(gsr0 + 0x10) & err);
}
static void mctl_channel_init(int ch_index, struct dram_sun6i_para *para)
{
struct sunxi_mctl_com_reg * const mctl_com =
(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
struct sunxi_mctl_ctl_reg *mctl_ctl;
struct sunxi_mctl_phy_reg *mctl_phy;
if (ch_index == 0) {
mctl_ctl = (struct sunxi_mctl_ctl_reg *)SUNXI_DRAM_CTL0_BASE;
mctl_phy = (struct sunxi_mctl_phy_reg *)SUNXI_DRAM_PHY0_BASE;
} else {
mctl_ctl = (struct sunxi_mctl_ctl_reg *)SUNXI_DRAM_CTL1_BASE;
mctl_phy = (struct sunxi_mctl_phy_reg *)SUNXI_DRAM_PHY1_BASE;
}
writel(MCTL_MCMD_NOP, &mctl_ctl->mcmd);
mctl_await_completion(&mctl_ctl->mcmd, MCTL_MCMD_BUSY, 0);
/* PHY initialization */
writel(MCTL_PGCR, &mctl_phy->pgcr);
writel(MCTL_MR0, &mctl_phy->mr0);
writel(MCTL_MR1, &mctl_phy->mr1);
writel(MCTL_MR2, &mctl_phy->mr2);
writel(MCTL_MR3, &mctl_phy->mr3);
writel((MCTL_TITMSRST << 18) | (MCTL_TDLLLOCK << 6) | MCTL_TDLLSRST,
&mctl_phy->ptr0);
writel((MCTL_TDINIT1 << 19) | MCTL_TDINIT0, &mctl_phy->ptr1);
writel((MCTL_TDINIT3 << 17) | MCTL_TDINIT2, &mctl_phy->ptr2);
writel((MCTL_TCCD << 31) | (MCTL_TRC << 25) | (MCTL_TRRD << 21) |
(MCTL_TRAS << 16) | (MCTL_TRCD << 12) | (MCTL_TRP << 8) |
(MCTL_TWTR << 5) | (MCTL_TRTP << 2) | (MCTL_TMRD << 0),
&mctl_phy->dtpr0);
writel((MCTL_TDQSCKMAX << 27) | (MCTL_TDQSCK << 24) |
(MCTL_TRFC << 16) | (MCTL_TRTODT << 11) |
((MCTL_TMOD - 12) << 9) | (MCTL_TFAW << 3) | (0 << 2) |
(MCTL_TAOND << 0), &mctl_phy->dtpr1);
writel((MCTL_TDLLK << 19) | (MCTL_TCKE << 15) | (MCTL_TXPDLL << 10) |
(MCTL_TEXSR << 0), &mctl_phy->dtpr2);
writel(1, &mctl_ctl->dfitphyupdtype0);
writel(MCTL_DCR_DDR3, &mctl_phy->dcr);
writel(MCTL_DSGCR, &mctl_phy->dsgcr);
writel(MCTL_DXCCR, &mctl_phy->dxccr);
writel(MCTL_DX_GCR | MCTL_DX_GCR_EN, &mctl_phy->dx0gcr);
writel(MCTL_DX_GCR | MCTL_DX_GCR_EN, &mctl_phy->dx1gcr);
writel(MCTL_DX_GCR | MCTL_DX_GCR_EN, &mctl_phy->dx2gcr);
writel(MCTL_DX_GCR | MCTL_DX_GCR_EN, &mctl_phy->dx3gcr);
mctl_await_completion(&mctl_phy->pgsr, 0x03, 0x03);
writel(CONFIG_DRAM_ZQ, &mctl_phy->zq0cr1);
setbits_le32(&mctl_phy->pir, MCTL_PIR_CLEAR_STATUS);
writel(MCTL_PIR_STEP1, &mctl_phy->pir);
udelay(10);
mctl_await_completion(&mctl_phy->pgsr, 0x1f, 0x1f);
/* rank detect */
if (!mctl_rank_detect(&mctl_phy->dx0gsr0, 1)) {
para->rank = 1;
clrbits_le32(&mctl_phy->pgcr, MCTL_PGCR_RANK);
}
/*
* channel detect, check channel 1 dx0 and dx1 have rank 0, if not
* assume nothing is connected to channel 1.
*/
if (ch_index == 1 && !mctl_rank_detect(&mctl_phy->dx0gsr0, 0)) {
para->chan = 1;
clrbits_le32(&mctl_com->ccr, MCTL_CCR_CH1_CLK_EN);
return;
}
/* bus width detect, if dx2 and dx3 don't have rank 0, assume 16 bit */
if (!mctl_rank_detect(&mctl_phy->dx2gsr0, 0)) {
para->bus_width = 16;
para->page_size = 2048;
setbits_le32(&mctl_phy->dx2dllcr, MCTL_DLLCR_DISABLE);
setbits_le32(&mctl_phy->dx3dllcr, MCTL_DLLCR_DISABLE);
clrbits_le32(&mctl_phy->dx2gcr, MCTL_DX_GCR_EN);
clrbits_le32(&mctl_phy->dx3gcr, MCTL_DX_GCR_EN);
}
setbits_le32(&mctl_phy->pir, MCTL_PIR_CLEAR_STATUS);
writel(MCTL_PIR_STEP2, &mctl_phy->pir);
udelay(10);
mctl_await_completion(&mctl_phy->pgsr, 0x11, 0x11);
if (readl(&mctl_phy->pgsr) & MCTL_PGSR_TRAIN_ERR_MASK)
panic("Training error initialising DRAM\n");
/* Move to configure state */
writel(MCTL_SCTL_CONFIG, &mctl_ctl->sctl);
mctl_await_completion(&mctl_ctl->sstat, 0x07, 0x01);
/* Set number of clks per micro-second */
writel(DRAM_CLK / 1000000, &mctl_ctl->togcnt1u);
/* Set number of clks per 100 nano-seconds */
writel(DRAM_CLK / 10000000, &mctl_ctl->togcnt100n);
/* Set memory timing registers */
writel(MCTL_TREFI, &mctl_ctl->trefi);
writel(MCTL_TMRD, &mctl_ctl->tmrd);
writel(MCTL_TRFC, &mctl_ctl->trfc);
writel((MCTL_TPREA << 16) | MCTL_TRP, &mctl_ctl->trp);
writel(MCTL_TRTW, &mctl_ctl->trtw);
writel(MCTL_TAL, &mctl_ctl->tal);
writel(MCTL_TCL, &mctl_ctl->tcl);
writel(MCTL_TCWL, &mctl_ctl->tcwl);
writel(MCTL_TRAS, &mctl_ctl->tras);
writel(MCTL_TRC, &mctl_ctl->trc);
writel(MCTL_TRCD, &mctl_ctl->trcd);
writel(MCTL_TRRD, &mctl_ctl->trrd);
writel(MCTL_TRTP, &mctl_ctl->trtp);
writel(MCTL_TWR, &mctl_ctl->twr);
writel(MCTL_TWTR, &mctl_ctl->twtr);
writel(MCTL_TEXSR, &mctl_ctl->texsr);
writel(MCTL_TXP, &mctl_ctl->txp);
writel(MCTL_TXPDLL, &mctl_ctl->txpdll);
writel(MCTL_TZQCS, &mctl_ctl->tzqcs);
writel(MCTL_TZQCSI, &mctl_ctl->tzqcsi);
writel(MCTL_TDQS, &mctl_ctl->tdqs);
writel(MCTL_TCKSRE, &mctl_ctl->tcksre);
writel(MCTL_TCKSRX, &mctl_ctl->tcksrx);
writel(MCTL_TCKE, &mctl_ctl->tcke);
writel(MCTL_TMOD, &mctl_ctl->tmod);
writel(MCTL_TRSTL, &mctl_ctl->trstl);
writel(MCTL_TZQCL, &mctl_ctl->tzqcl);
writel(MCTL_TMRR, &mctl_ctl->tmrr);
writel(MCTL_TCKESR, &mctl_ctl->tckesr);
writel(MCTL_TDPD, &mctl_ctl->tdpd);
/* Unknown magic performed by boot0 */
setbits_le32(&mctl_ctl->dfiodtcfg, 1 << 3);
clrbits_le32(&mctl_ctl->dfiodtcfg1, 0x1f);
/* Select 16/32-bits mode for MCTL */
if (para->bus_width == 16)
setbits_le32(&mctl_ctl->ppcfg, 1);
/* Set DFI timing registers */
writel(MCTL_TCWL, &mctl_ctl->dfitphywrl);
writel(MCTL_TCL - 1, &mctl_ctl->dfitrdden);
writel(MCTL_DFITPHYRDL, &mctl_ctl->dfitphyrdl);
writel(MCTL_DFISTCFG0, &mctl_ctl->dfistcfg0);
writel(MCTL_MCFG_DDR3, &mctl_ctl->mcfg);
/* DFI update configuration register */
writel(MCTL_DFIUPDCFG_UPD, &mctl_ctl->dfiupdcfg);
/* Move to access state */
writel(MCTL_SCTL_ACCESS, &mctl_ctl->sctl);
mctl_await_completion(&mctl_ctl->sstat, 0x07, 0x03);
}
static void mctl_com_init(struct dram_sun6i_para *para)
{
struct sunxi_mctl_com_reg * const mctl_com =
(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
struct sunxi_mctl_phy_reg * const mctl_phy1 =
(struct sunxi_mctl_phy_reg *)SUNXI_DRAM_PHY1_BASE;
struct sunxi_prcm_reg * const prcm =
(struct sunxi_prcm_reg *)SUNXI_PRCM_BASE;
writel(MCTL_CR_UNKNOWN | MCTL_CR_CHANNEL(para->chan) | MCTL_CR_DDR3 |
((para->bus_width == 32) ? MCTL_CR_BUSW32 : MCTL_CR_BUSW16) |
MCTL_CR_PAGE_SIZE(para->page_size) | MCTL_CR_ROW(para->rows) |
MCTL_CR_BANK(1) | MCTL_CR_RANK(para->rank), &mctl_com->cr);
/* Unknown magic performed by boot0 */
setbits_le32(&mctl_com->dbgcr, (1 << 6));
if (para->chan == 1) {
/* Shutdown channel 1 */
setbits_le32(&mctl_phy1->aciocr, MCTL_ACIOCR_DISABLE);
setbits_le32(&mctl_phy1->dxccr, MCTL_DXCCR_DISABLE);
clrbits_le32(&mctl_phy1->dsgcr, MCTL_DSGCR_ENABLE);
/*
* CH0 ?? this is what boot0 does. Leave as is until we can
* confirm this.
*/
setbits_le32(&prcm->vdd_sys_pwroff,
PRCM_VDD_SYS_DRAM_CH0_PAD_HOLD_PWROFF);
}
}
static void mctl_port_cfg(void)
{
struct sunxi_mctl_com_reg * const mctl_com =
(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
struct sunxi_ccm_reg * const ccm =
(struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
/* enable DRAM AXI clock for CPU access */
setbits_le32(&ccm->axi_gate, 1 << AXI_GATE_OFFSET_DRAM);
/* Bunch of magic writes performed by boot0 */
writel(0x00400302, &mctl_com->rmcr[0]);
writel(0x01000307, &mctl_com->rmcr[1]);
writel(0x00400302, &mctl_com->rmcr[2]);
writel(0x01000307, &mctl_com->rmcr[3]);
writel(0x01000307, &mctl_com->rmcr[4]);
writel(0x01000303, &mctl_com->rmcr[6]);
writel(0x01000303, &mctl_com->mmcr[0]);
writel(0x00400310, &mctl_com->mmcr[1]);
writel(0x01000307, &mctl_com->mmcr[2]);
writel(0x01000303, &mctl_com->mmcr[3]);
writel(0x01800303, &mctl_com->mmcr[4]);
writel(0x01800303, &mctl_com->mmcr[5]);
writel(0x01800303, &mctl_com->mmcr[6]);
writel(0x01800303, &mctl_com->mmcr[7]);
writel(0x01000303, &mctl_com->mmcr[8]);
writel(0x00000002, &mctl_com->mmcr[15]);
writel(0x00000310, &mctl_com->mbagcr[0]);
writel(0x00400310, &mctl_com->mbagcr[1]);
writel(0x00400310, &mctl_com->mbagcr[2]);
writel(0x00000307, &mctl_com->mbagcr[3]);
writel(0x00000317, &mctl_com->mbagcr[4]);
writel(0x00000307, &mctl_com->mbagcr[5]);
}
unsigned long sunxi_dram_init(void)
{
struct sunxi_mctl_com_reg * const mctl_com =
(struct sunxi_mctl_com_reg *)SUNXI_DRAM_COM_BASE;
u32 offset;
int bank, bus, columns;
/* Set initial parameters, these get modified by the autodetect code */
struct dram_sun6i_para para = {
.bus_width = 32,
.chan = 2,
.rank = 2,
.page_size = 4096,
.rows = 16,
};
/* A31s only has one channel */
if (sunxi_get_ss_bonding_id() == SUNXI_SS_BOND_ID_A31S)
para.chan = 1;
mctl_sys_init();
mctl_dll_init(0, &para);
setbits_le32(&mctl_com->ccr, MCTL_CCR_CH0_CLK_EN);
if (para.chan == 2) {
mctl_dll_init(1, &para);
setbits_le32(&mctl_com->ccr, MCTL_CCR_CH1_CLK_EN);
}
setbits_le32(&mctl_com->ccr, MCTL_CCR_MASTER_CLK_EN);
mctl_channel_init(0, &para);
if (para.chan == 2)
mctl_channel_init(1, &para);
mctl_com_init(&para);
mctl_port_cfg();
/*
* Change to 1 ch / sequence / 8192 byte pages / 16 rows /
* 8 bit banks / 1 rank mode.
*/
clrsetbits_le32(&mctl_com->cr,
MCTL_CR_CHANNEL_MASK | MCTL_CR_PAGE_SIZE_MASK |
MCTL_CR_ROW_MASK | MCTL_CR_BANK_MASK | MCTL_CR_RANK_MASK,
MCTL_CR_CHANNEL(1) | MCTL_CR_SEQUENCE |
MCTL_CR_PAGE_SIZE(8192) | MCTL_CR_ROW(16) |
MCTL_CR_BANK(1) | MCTL_CR_RANK(1));
/* Detect and set page size */
for (columns = 7; columns < 20; columns++) {
if (mctl_mem_matches(1 << columns))
break;
}
bus = (para.bus_width == 32) ? 2 : 1;
columns -= bus;
para.page_size = (1 << columns) * (bus << 1);
clrsetbits_le32(&mctl_com->cr, MCTL_CR_PAGE_SIZE_MASK,
MCTL_CR_PAGE_SIZE(para.page_size));
/* Detect and set rows */
for (para.rows = 11; para.rows < 16; para.rows++) {
offset = 1 << (para.rows + columns + bus);
if (mctl_mem_matches(offset))
break;
}
clrsetbits_le32(&mctl_com->cr, MCTL_CR_ROW_MASK,
MCTL_CR_ROW(para.rows));
/* Detect bank size */
offset = 1 << (para.rows + columns + bus + 2);
bank = mctl_mem_matches(offset) ? 0 : 1;
/* Restore interleave, chan and rank values, set bank size */
clrsetbits_le32(&mctl_com->cr,
MCTL_CR_CHANNEL_MASK | MCTL_CR_SEQUENCE |
MCTL_CR_BANK_MASK | MCTL_CR_RANK_MASK,
MCTL_CR_CHANNEL(para.chan) | MCTL_CR_BANK(bank) |
MCTL_CR_RANK(para.rank));
return 1 << (para.rank + para.rows + bank + columns + para.chan + bus);
}