ARM: OMAP2+: gpmc: Keep Chip Select disabled while configuring it

As per the OMAP reference manual [1], the Chip Select must be
disabled (i.e. CSVALID is 0) while configuring any of the
Chip select parameters.

[1] - 10.1.5.1 Chip-Select Base Address and Region Size Configuration
http://www.ti.com/lit/pdf/swpu177

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
This commit is contained in:
Roger Quadros 2014-08-29 19:11:53 +03:00
parent e378d22b9c
commit 4cf27d2ec7

View File

@ -397,7 +397,7 @@ int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t)
return 0;
}
static int gpmc_cs_enable_mem(int cs, u32 base, u32 size)
static int gpmc_cs_set_memconf(int cs, u32 base, u32 size)
{
u32 l;
u32 mask;
@ -421,6 +421,15 @@ static int gpmc_cs_enable_mem(int cs, u32 base, u32 size)
return 0;
}
static void gpmc_cs_enable_mem(int cs)
{
u32 l;
l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
l |= GPMC_CONFIG7_CSVALID;
gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
}
static void gpmc_cs_disable_mem(int cs)
{
u32 l;
@ -532,18 +541,18 @@ static int gpmc_cs_remap(int cs, u32 base)
gpmc_cs_get_memconf(cs, &old_base, &size);
if (base == old_base)
return 0;
gpmc_cs_disable_mem(cs);
ret = gpmc_cs_delete_mem(cs);
if (ret < 0)
return ret;
ret = gpmc_cs_insert_mem(cs, base, size);
if (ret < 0)
return ret;
ret = gpmc_cs_enable_mem(cs, base, size);
if (ret < 0)
return ret;
return 0;
ret = gpmc_cs_set_memconf(cs, base, size);
return ret;
}
int gpmc_cs_request(int cs, unsigned long size, unsigned long *base)
@ -572,12 +581,17 @@ int gpmc_cs_request(int cs, unsigned long size, unsigned long *base)
if (r < 0)
goto out;
r = gpmc_cs_enable_mem(cs, res->start, resource_size(res));
/* Disable CS while changing base address and size mask */
gpmc_cs_disable_mem(cs);
r = gpmc_cs_set_memconf(cs, res->start, resource_size(res));
if (r < 0) {
release_resource(res);
goto out;
}
/* Enable CS */
gpmc_cs_enable_mem(cs);
*base = res->start;
gpmc_cs_set_reserved(cs, 1);
out:
@ -1539,6 +1553,9 @@ static int gpmc_probe_generic_child(struct platform_device *pdev,
goto no_timings;
}
/* CS must be disabled while making changes to gpmc configuration */
gpmc_cs_disable_mem(cs);
/*
* FIXME: gpmc_cs_request() will map the CS to an arbitary
* location in the gpmc address space. When booting with
@ -1577,6 +1594,9 @@ static int gpmc_probe_generic_child(struct platform_device *pdev,
val &= ~GPMC_CONFIG_LIMITEDADDRESS;
gpmc_write_reg(GPMC_CONFIG, val);
/* Enable CS region */
gpmc_cs_enable_mem(cs);
no_timings:
if (of_platform_device_create(child, NULL, &pdev->dev))
return 0;