Commit 4cf27d2e authored by Roger Quadros's avatar Roger Quadros
Browse files

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: default avatarRoger Quadros <rogerq@ti.com>
Signed-off-by: default avatarSekhar Nori <nsekhar@ti.com>
Acked-by: default avatarTony Lindgren <tony@atomide.com>
parent e378d22b

arch/arm/mach-omap2/gpmc.c

+27 −7
Original line number Diff line number Diff line
@@ -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;

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