memory: emif: add device tree support to emif driver
Device tree support for the EMIF driver. LPDDR2 generic timings
extraction from device is managed using couple of helper
functions which can be used by other memory controller
drivers.
Reviewed-by: Benoit Cousson <b-cousson@ti.com>
Reviewed-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Aneesh V <aneesh@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/memory/emif.c b/drivers/memory/emif.c
index 33a4396..1424ae3 100644
--- a/drivers/memory/emif.c
+++ b/drivers/memory/emif.c
@@ -18,6 +18,7 @@
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
+#include <linux/of.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/module.h>
@@ -25,6 +26,7 @@
#include <linux/spinlock.h>
#include <memory/jedec_ddr.h>
#include "emif.h"
+#include "of_memory.h"
/**
* struct emif_data - Per device static data for driver's use
@@ -49,6 +51,7 @@
* frequency in effect at the moment)
* @plat_data: Pointer to saved platform data.
* @debugfs_root: dentry to the root folder for EMIF in debugfs
+ * @np_ddr: Pointer to ddr device tree node
*/
struct emif_data {
u8 duplicate;
@@ -63,6 +66,7 @@
struct emif_regs *curr_regs;
struct emif_platform_data *plat_data;
struct dentry *debugfs_root;
+ struct device_node *np_ddr;
};
static struct emif_data *emif1;
@@ -1148,6 +1152,168 @@
return valid;
}
+#if defined(CONFIG_OF)
+static void __init_or_module of_get_custom_configs(struct device_node *np_emif,
+ struct emif_data *emif)
+{
+ struct emif_custom_configs *cust_cfgs = NULL;
+ int len;
+ const int *lpmode, *poll_intvl;
+
+ lpmode = of_get_property(np_emif, "low-power-mode", &len);
+ poll_intvl = of_get_property(np_emif, "temp-alert-poll-interval", &len);
+
+ if (lpmode || poll_intvl)
+ cust_cfgs = devm_kzalloc(emif->dev, sizeof(*cust_cfgs),
+ GFP_KERNEL);
+
+ if (!cust_cfgs)
+ return;
+
+ if (lpmode) {
+ cust_cfgs->mask |= EMIF_CUSTOM_CONFIG_LPMODE;
+ cust_cfgs->lpmode = *lpmode;
+ of_property_read_u32(np_emif,
+ "low-power-mode-timeout-performance",
+ &cust_cfgs->lpmode_timeout_performance);
+ of_property_read_u32(np_emif,
+ "low-power-mode-timeout-power",
+ &cust_cfgs->lpmode_timeout_power);
+ of_property_read_u32(np_emif,
+ "low-power-mode-freq-threshold",
+ &cust_cfgs->lpmode_freq_threshold);
+ }
+
+ if (poll_intvl) {
+ cust_cfgs->mask |=
+ EMIF_CUSTOM_CONFIG_TEMP_ALERT_POLL_INTERVAL;
+ cust_cfgs->temp_alert_poll_interval_ms = *poll_intvl;
+ }
+
+ if (!is_custom_config_valid(cust_cfgs, emif->dev)) {
+ devm_kfree(emif->dev, cust_cfgs);
+ return;
+ }
+
+ emif->plat_data->custom_configs = cust_cfgs;
+}
+
+static void __init_or_module of_get_ddr_info(struct device_node *np_emif,
+ struct device_node *np_ddr,
+ struct ddr_device_info *dev_info)
+{
+ u32 density = 0, io_width = 0;
+ int len;
+
+ if (of_find_property(np_emif, "cs1-used", &len))
+ dev_info->cs1_used = true;
+
+ if (of_find_property(np_emif, "cal-resistor-per-cs", &len))
+ dev_info->cal_resistors_per_cs = true;
+
+ if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s4"))
+ dev_info->type = DDR_TYPE_LPDDR2_S4;
+ else if (of_device_is_compatible(np_ddr , "jedec,lpddr2-s2"))
+ dev_info->type = DDR_TYPE_LPDDR2_S2;
+
+ of_property_read_u32(np_ddr, "density", &density);
+ of_property_read_u32(np_ddr, "io-width", &io_width);
+
+ /* Convert from density in Mb to the density encoding in jedc_ddr.h */
+ if (density & (density - 1))
+ dev_info->density = 0;
+ else
+ dev_info->density = __fls(density) - 5;
+
+ /* Convert from io_width in bits to io_width encoding in jedc_ddr.h */
+ if (io_width & (io_width - 1))
+ dev_info->io_width = 0;
+ else
+ dev_info->io_width = __fls(io_width) - 1;
+}
+
+static struct emif_data * __init_or_module of_get_memory_device_details(
+ struct device_node *np_emif, struct device *dev)
+{
+ struct emif_data *emif = NULL;
+ struct ddr_device_info *dev_info = NULL;
+ struct emif_platform_data *pd = NULL;
+ struct device_node *np_ddr;
+ int len;
+
+ np_ddr = of_parse_phandle(np_emif, "device-handle", 0);
+ if (!np_ddr)
+ goto error;
+ emif = devm_kzalloc(dev, sizeof(struct emif_data), GFP_KERNEL);
+ pd = devm_kzalloc(dev, sizeof(*pd), GFP_KERNEL);
+ dev_info = devm_kzalloc(dev, sizeof(*dev_info), GFP_KERNEL);
+
+ if (!emif || !pd || !dev_info) {
+ dev_err(dev, "%s: Out of memory!!\n",
+ __func__);
+ goto error;
+ }
+
+ emif->plat_data = pd;
+ pd->device_info = dev_info;
+ emif->dev = dev;
+ emif->np_ddr = np_ddr;
+ emif->temperature_level = SDRAM_TEMP_NOMINAL;
+
+ if (of_device_is_compatible(np_emif, "ti,emif-4d"))
+ emif->plat_data->ip_rev = EMIF_4D;
+ else if (of_device_is_compatible(np_emif, "ti,emif-4d5"))
+ emif->plat_data->ip_rev = EMIF_4D5;
+
+ of_property_read_u32(np_emif, "phy-type", &pd->phy_type);
+
+ if (of_find_property(np_emif, "hw-caps-ll-interface", &len))
+ pd->hw_caps |= EMIF_HW_CAPS_LL_INTERFACE;
+
+ of_get_ddr_info(np_emif, np_ddr, dev_info);
+ if (!is_dev_data_valid(pd->device_info->type, pd->device_info->density,
+ pd->device_info->io_width, pd->phy_type, pd->ip_rev,
+ emif->dev)) {
+ dev_err(dev, "%s: invalid device data!!\n", __func__);
+ goto error;
+ }
+ /*
+ * For EMIF instances other than EMIF1 see if the devices connected
+ * are exactly same as on EMIF1(which is typically the case). If so,
+ * mark it as a duplicate of EMIF1. This will save some memory and
+ * computation.
+ */
+ if (emif1 && emif1->np_ddr == np_ddr) {
+ emif->duplicate = true;
+ goto out;
+ } else if (emif1) {
+ dev_warn(emif->dev, "%s: Non-symmetric DDR geometry\n",
+ __func__);
+ }
+
+ of_get_custom_configs(np_emif, emif);
+ emif->plat_data->timings = of_get_ddr_timings(np_ddr, emif->dev,
+ emif->plat_data->device_info->type,
+ &emif->plat_data->timings_arr_size);
+
+ emif->plat_data->min_tck = of_get_min_tck(np_ddr, emif->dev);
+ goto out;
+
+error:
+ return NULL;
+out:
+ return emif;
+}
+
+#else
+
+static struct emif_data * __init_or_module of_get_memory_device_details(
+ struct device_node *np_emif, struct device *dev)
+{
+ return NULL;
+}
+#endif
+
static struct emif_data *__init_or_module get_device_details(
struct platform_device *pdev)
{
@@ -1267,7 +1433,11 @@
struct resource *res;
int irq;
- emif = get_device_details(pdev);
+ if (pdev->dev.of_node)
+ emif = of_get_memory_device_details(pdev->dev.of_node, &pdev->dev);
+ else
+ emif = get_device_details(pdev);
+
if (!emif) {
pr_err("%s: error getting device data\n", __func__);
goto error;
@@ -1644,11 +1814,21 @@
spin_unlock_irqrestore(&emif_lock, irq_state);
}
+#if defined(CONFIG_OF)
+static const struct of_device_id emif_of_match[] = {
+ { .compatible = "ti,emif-4d" },
+ { .compatible = "ti,emif-4d5" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, emif_of_match);
+#endif
+
static struct platform_driver emif_driver = {
.remove = __exit_p(emif_remove),
.shutdown = emif_shutdown,
.driver = {
.name = "emif",
+ .of_match_table = of_match_ptr(emif_of_match),
},
};