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bus: omap-gpmc: Add Generic device support 

This adds support for generic devices like NOR flash and
ethernet to the gpmc bus driver.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
This commit is contained in:
Sascha Hauer 2015-06-19 06:09:19 +02:00
parent 08120e2166
commit 5c29d3627e
1 changed files with 142 additions and 0 deletions
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142
drivers/bus/omap-gpmc.c
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@ -24,6 +24,14 @@
#define GPMC_CS_NUM 8
#define GPMC_NR_WAITPINS 4
#define GPMC_BURST_4 4 /* 4 word burst */
#define GPMC_BURST_8 8 /* 8 word burst */
#define GPMC_BURST_16 16 /* 16 word burst */
#define GPMC_DEVWIDTH_8BIT 1 /* 8-bit device width */
#define GPMC_DEVWIDTH_16BIT 2 /* 16-bit device width */
#define GPMC_MUX_AAD 1 /* Addr-Addr-Data multiplex */
#define GPMC_MUX_AD 2 /* Addr-Data multiplex */
#define GPMC_CONFIG1_WRAPBURST_SUPP (1 << 31)
#define GPMC_CONFIG1_READMULTIPLE_SUPP (1 << 30)
#define GPMC_CONFIG1_READTYPE_ASYNC (0 << 29)
@ -55,6 +63,9 @@
#define GPMC_CONFIG6_CYCLE2CYCLESAMECSEN (1 << 7)
#define GPMC_CONFIG7_CSVALID (1 << 6)
#define GPMC_DEVICETYPE_NOR 0
#define GPMC_DEVICETYPE_NAND 2
static unsigned int gpmc_cs_num = GPMC_CS_NUM;
static unsigned int gpmc_nr_waitpins;
static unsigned long gpmc_l3_clk = 100000000; /* This should be a proper clock */
@ -220,6 +231,8 @@ static int gpmc_timings_to_config(struct gpmc_config *gpmc_config, const struct
if (div < 0)
return div;
gpmc_config->cfg[0] |= div - 1;
ret |= set_cfg(gpmc_config, 0, 18, 19, t->wait_monitoring);
ret |= set_cfg(gpmc_config, 0, 25, 26, t->clk_activation);
@ -255,6 +268,60 @@ static int gpmc_timings_to_config(struct gpmc_config *gpmc_config, const struct
return 0;
}
static int gpmc_settings_to_config(struct gpmc_config *gpmc_config,
struct gpmc_settings *p)
{
u32 config1 = gpmc_config->cfg[0];
/* Page/burst mode supports lengths of 4, 8 and 16 bytes */
if (p->burst_read || p->burst_write) {
switch (p->burst_len) {
case GPMC_BURST_4:
case GPMC_BURST_8:
case GPMC_BURST_16:
break;
default:
pr_err("%s: invalid page/burst-length (%d)\n",
__func__, p->burst_len);
return -EINVAL;
}
}
if (p->wait_pin > gpmc_nr_waitpins) {
pr_err("%s: invalid wait-pin (%d)\n", __func__, p->wait_pin);
return -EINVAL;
}
config1 |= GPMC_CONFIG1_DEVICESIZE((p->device_width - 1));
if (p->sync_read)
config1 |= GPMC_CONFIG1_READTYPE_SYNC;
if (p->sync_write)
config1 |= GPMC_CONFIG1_WRITETYPE_SYNC;
if (p->wait_on_read)
config1 |= GPMC_CONFIG1_WAIT_READ_MON;
if (p->wait_on_write)
config1 |= GPMC_CONFIG1_WAIT_WRITE_MON;
if (p->wait_on_read || p->wait_on_write)
config1 |= GPMC_CONFIG1_WAIT_PIN_SEL(p->wait_pin);
if (p->device_nand)
config1 |= GPMC_CONFIG1_DEVICETYPE(GPMC_DEVICETYPE_NAND);
if (p->mux_add_data)
config1 |= GPMC_CONFIG1_MUXTYPE(p->mux_add_data);
if (p->burst_read)
config1 |= GPMC_CONFIG1_READMULTIPLE_SUPP;
if (p->burst_write)
config1 |= GPMC_CONFIG1_WRITEMULTIPLE_SUPP;
if (p->burst_read || p->burst_write) {
config1 |= GPMC_CONFIG1_PAGE_LEN(p->burst_len >> 3);
config1 |= p->burst_wrap ? GPMC_CONFIG1_WRAPBURST_SUPP : 0;
}
gpmc_config->cfg[0] = config1;
return 0;
}
/**
* gpmc_read_settings_dt - read gpmc settings from device-tree
* @np: pointer to device-tree node for a gpmc child device
@ -464,6 +531,77 @@ static int gpmc_probe_nand_child(struct device_d *dev,
return 0;
}
/**
* gpmc_probe_generic_child - configures the gpmc for a child device
* @pdev: pointer to gpmc platform device
* @child: pointer to device-tree node for child device
*
* Allocates and configures a GPMC chip-select for a child device.
* Returns 0 on success and appropriate negative error code on failure.
*/
static int gpmc_probe_generic_child(struct device_d *dev,
struct device_node *child)
{
struct gpmc_settings gpmc_s = {};
struct gpmc_timings gpmc_t = {};
struct resource res;
int ret, cs;
struct gpmc_config cfg = {};
resource_size_t size;
if (of_property_read_u32(child, "reg", &cs) < 0) {
dev_err(dev, "%s has no 'reg' property\n",
child->full_name);
return -ENODEV;
}
if (of_address_to_resource(child, 0, &res) < 0) {
dev_err(dev, "%s has malformed 'reg' property\n",
child->full_name);
return -ENODEV;
}
gpmc_read_settings_dt(child, &gpmc_s);
gpmc_read_timings_dt(child, &gpmc_t);
ret = of_property_read_u32(child, "bank-width", &gpmc_s.device_width);
if (ret < 0)
goto err;
gpmc_timings_to_config(&cfg, &gpmc_t);
cfg.base = res.start;
size = resource_size(&res);
if (size > SZ_64M)
cfg.size = GPMC_SIZE_128M;
else if (size > SZ_32M)
cfg.size = GPMC_SIZE_64M;
else if (size > SZ_16M)
cfg.size = GPMC_SIZE_32M;
else
cfg.size = GPMC_SIZE_16M;
gpmc_settings_to_config(&cfg, &gpmc_s);
gpmc_cs_config(cs, &cfg);
/* create platform device, NULL on error or when disabled */
if (of_get_property(child, "compatible", NULL) && !of_platform_device_create(child, dev))
goto err_child_fail;
return 0;
err_child_fail:
dev_err(dev, "failed to create gpmc child %s\n", child->name);
ret = -ENODEV;
err:
return ret;
}
static int gpmc_probe(struct device_d *dev)
{
struct device_node *child, *node = dev->device_node;
@ -488,6 +626,10 @@ static int gpmc_probe(struct device_d *dev)
if (!strncmp(child->name, "nand", 4))
ret = gpmc_probe_nand_child(dev, child);
else if (strncmp(child->name, "ethernet", 8) == 0 ||
strncmp(child->name, "nor", 3) == 0 ||
strncmp(child->name, "uart", 4) == 0)
ret = gpmc_probe_generic_child(dev, child);
else
dev_warn(dev, "unhandled child %s\n", child->name);