diff options
| author | Yuri Tikhonov <yur@emcraft.com> | 2008-10-17 12:54:18 +0200 |
|---|---|---|
| committer | Wolfgang Denk <wd@denx.de> | 2008-10-17 13:02:42 +0200 |
| commit | bf29e0ea0af03d593c64614136acc723a7a022a2 (patch) | |
| tree | 118a069b493e29e96192ac1d50c08d913509d6da /cpu | |
| parent | f7d190b1c0b3ab7fc53074ad2862f7de99de37ff (diff) | |
ppc4xx: PPC44x MQ initialization
Set the MQ Read Passing & MCIF Cycle limits to the recommended by AMCC
values. This fixes the occasional 440SPe hard locking issues when the 440SPe's
dedicated DMA engines are used (e.g. by the h/w accelerated RAID driver).
Previously the appropriate initialization had been made in Linux, by the
ppc440spe ADMA driver, which is wrong because modifying the MQ configuration
registers after normal operation has begun is not supported and could
have unpredictable results.
Comment from Stefan: This patch doesn't change the resulting value of the
MQ registers. It explicitly sets/clears all bits to the desired state which
better documents the resulting register value instead of relying on pre-set
default values.
Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Stefan Roese <sr@denx.de>
Diffstat (limited to 'cpu')
| -rw-r--r-- | cpu/ppc4xx/44x_spd_ddr2.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/cpu/ppc4xx/44x_spd_ddr2.c b/cpu/ppc4xx/44x_spd_ddr2.c index f1d76840f21..995d5fec747 100644 --- a/cpu/ppc4xx/44x_spd_ddr2.c +++ b/cpu/ppc4xx/44x_spd_ddr2.c @@ -2261,10 +2261,12 @@ static void program_memory_queue(unsigned long *dimm_populated, /* * Set optimal value for Memory Queue HB/LL Configuration registers */ - mtdcr(SDRAM_CONF1HB, mfdcr(SDRAM_CONF1HB) | SDRAM_CONF1HB_AAFR | - SDRAM_CONF1HB_RPEN | SDRAM_CONF1HB_RFTE); - mtdcr(SDRAM_CONF1LL, mfdcr(SDRAM_CONF1LL) | SDRAM_CONF1LL_AAFR | - SDRAM_CONF1LL_RPEN | SDRAM_CONF1LL_RFTE); + mtdcr(SDRAM_CONF1HB, (mfdcr(SDRAM_CONF1HB) & ~SDRAM_CONF1HB_MASK) | + SDRAM_CONF1HB_AAFR | SDRAM_CONF1HB_RPEN | SDRAM_CONF1HB_RFTE | + SDRAM_CONF1HB_RPLM | SDRAM_CONF1HB_WRCL); + mtdcr(SDRAM_CONF1LL, (mfdcr(SDRAM_CONF1LL) & ~SDRAM_CONF1LL_MASK) | + SDRAM_CONF1LL_AAFR | SDRAM_CONF1LL_RPEN | SDRAM_CONF1LL_RFTE | + SDRAM_CONF1LL_RPLM); mtdcr(SDRAM_CONFPATHB, mfdcr(SDRAM_CONFPATHB) | SDRAM_CONFPATHB_TPEN); #endif } |