[PATCH v6 13/14] mtd: onenand: omap2: Configure driver from DT

Ladislav Michl
2018-01-12T13:17:25Z

Move away from platform data configuration and use pure DT approach.

Use generic probe function to deal with OneNAND node and remove now useless
gpmc_probe_onenand_child function. Import sync mode timing calculation
function from mach-omap2/gpmc-onenand.c

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
---

Changes in v6:
- squashed with previous patch

Changes in v5:
- rename ready_gpiod to int_gpiod
- use int-gpios as property name
- use devm_ioremap_resource
- "onenand" is now requested irq name
- add Kconfig dependencies
- make gpmc_omap_onenand_set_timings decsription more descriptive

Changes in v4: None
Changes in v3:
- remove 'ti,omap3-onenand' compatible as it is not needed anymore

Changes in v2:
- move cleanups into separate patches
- simplify dma setup
- fix checkpatch error
- print info about otimized timings in sync mode only
- add gpmc_omap_onenand_set_timings description

drivers/memory/omap-gpmc.c | 158 ++++++++++++++++++++--------
drivers/mtd/onenand/Kconfig | 4 +-
drivers/mtd/onenand/omap2.c | 250 +++++++++++++++++++++++++++-----------------
include/linux/omap-gpmc.h | 28 +++++
4 files changed, 301 insertions(+), 139 deletions(-)

diff --git a/drivers/memory/omap-gpmc.c b/drivers/memory/omap-gpmc.c
index 0e30ee1c8677..90a66b3f7ae1 100644
--- a/drivers/memory/omap-gpmc.c
+++ b/drivers/memory/omap-gpmc.c
@@ -32,7 +32,6 @@
#include <linux/pm_runtime.h>

#include <linux/platform_data/mtd-nand-omap2.h>
-#include <linux/platform_data/mtd-onenand-omap2.h>

#include <asm/mach-types.h>

@@ -1138,6 +1137,112 @@ struct gpmc_nand_ops *gpmc_omap_get_nand_ops(struct gpmc_nand_regs *reg, int cs)
}
EXPORT_SYMBOL_GPL(gpmc_omap_get_nand_ops);

+static void gpmc_omap_onenand_calc_sync_timings(struct gpmc_timings *t,
+ struct gpmc_settings *s,
+ int freq, int latency)
+{
+ struct gpmc_device_timings dev_t;
+ const int t_cer = 15;
+ const int t_avdp = 12;
+ const int t_cez = 20; /* max of t_cez, t_oez */
+ const int t_wpl = 40;
+ const int t_wph = 30;
+ int min_gpmc_clk_period, t_ces, t_avds, t_avdh, t_ach, t_aavdh, t_rdyo;
+
+ switch (freq) {
+ case 104:
+ min_gpmc_clk_period = 9600; /* 104 MHz */
+ t_ces = 3;
+ t_avds = 4;
+ t_avdh = 2;
+ t_ach = 3;
+ t_aavdh = 6;
+ t_rdyo = 6;
+ break;
+ case 83:
+ min_gpmc_clk_period = 12000; /* 83 MHz */
+ t_ces = 5;
+ t_avds = 4;
+ t_avdh = 2;
+ t_ach = 6;
+ t_aavdh = 6;
+ t_rdyo = 9;
+ break;
+ case 66:
+ min_gpmc_clk_period = 15000; /* 66 MHz */
+ t_ces = 6;
+ t_avds = 5;
+ t_avdh = 2;
+ t_ach = 6;
+ t_aavdh = 6;
+ t_rdyo = 11;
+ break;
+ default:
+ min_gpmc_clk_period = 18500; /* 54 MHz */
+ t_ces = 7;
+ t_avds = 7;
+ t_avdh = 7;
+ t_ach = 9;
+ t_aavdh = 7;
+ t_rdyo = 15;
+ break;
+ }
+
+ /* Set synchronous read timings */
+ memset(&dev_t, 0, sizeof(dev_t));
+
+ if (!s->sync_write) {
+ dev_t.t_avdp_w = max(t_avdp, t_cer) * 1000;
+ dev_t.t_wpl = t_wpl * 1000;
+ dev_t.t_wph = t_wph * 1000;
+ dev_t.t_aavdh = t_aavdh * 1000;
+ }
+ dev_t.ce_xdelay = true;
+ dev_t.avd_xdelay = true;
+ dev_t.oe_xdelay = true;
+ dev_t.we_xdelay = true;
+ dev_t.clk = min_gpmc_clk_period;
+ dev_t.t_bacc = dev_t.clk;
+ dev_t.t_ces = t_ces * 1000;
+ dev_t.t_avds = t_avds * 1000;
+ dev_t.t_avdh = t_avdh * 1000;
+ dev_t.t_ach = t_ach * 1000;
+ dev_t.cyc_iaa = (latency + 1);
+ dev_t.t_cez_r = t_cez * 1000;
+ dev_t.t_cez_w = dev_t.t_cez_r;
+ dev_t.cyc_aavdh_oe = 1;
+ dev_t.t_rdyo = t_rdyo * 1000 + min_gpmc_clk_period;
+
+ gpmc_calc_timings(t, s, &dev_t);
+}
+
+int gpmc_omap_onenand_set_timings(struct device *dev, int cs, int freq,
+ int latency,
+ struct gpmc_onenand_info *info)
+{
+ int ret;
+ struct gpmc_timings gpmc_t;
+ struct gpmc_settings gpmc_s;
+
+ gpmc_read_settings_dt(dev->of_node, &gpmc_s);
+
+ info->sync_read = gpmc_s.sync_read;
+ info->sync_write = gpmc_s.sync_write;
+ info->burst_len = gpmc_s.burst_len;
+
+ if (!gpmc_s.sync_read && !gpmc_s.sync_write)
+ return 0;
+
+ gpmc_omap_onenand_calc_sync_timings(&gpmc_t, &gpmc_s, freq, latency);
+
+ ret = gpmc_cs_program_settings(cs, &gpmc_s);
+ if (ret < 0)
+ return ret;
+
+ return gpmc_cs_set_timings(cs, &gpmc_t, &gpmc_s);
+}
+EXPORT_SYMBOL_GPL(gpmc_omap_onenand_set_timings);
+
int gpmc_get_client_irq(unsigned irq_config)
{
if (!gpmc_irq_domain) {
@@ -1916,41 +2021,6 @@ static void __maybe_unused gpmc_read_timings_dt(struct device_node *np,
of_property_read_bool(np, "gpmc,time-para-granularity");
}

-#if IS_ENABLED(CONFIG_MTD_ONENAND)
-static int gpmc_probe_onenand_child(struct platform_device *pdev,
- struct device_node *child)
-{
- u32 val;
- struct omap_onenand_platform_data *gpmc_onenand_data;
-
- if (of_property_read_u32(child, "reg", &val) < 0) {
- dev_err(&pdev->dev, "%pOF has no 'reg' property\n",
- child);
- return -ENODEV;
- }
-
- gpmc_onenand_data = devm_kzalloc(&pdev->dev, sizeof(*gpmc_onenand_data),
- GFP_KERNEL);
- if (!gpmc_onenand_data)
- return -ENOMEM;
-
- gpmc_onenand_data->cs = val;
- gpmc_onenand_data->of_node = child;
- gpmc_onenand_data->dma_channel = -1;
-
- if (!of_property_read_u32(child, "dma-channel", &val))
- gpmc_onenand_data->dma_channel = val;
-
- return gpmc_onenand_init(gpmc_onenand_data);
-}
-#else
-static int gpmc_probe_onenand_child(struct platform_device *pdev,
- struct device_node *child)
-{
- return 0;
-}
-#endif
-
/**
* gpmc_probe_generic_child - configures the gpmc for a child device
* @pdev: pointer to gpmc platform device
@@ -2053,6 +2123,16 @@ static int gpmc_probe_generic_child(struct platform_device *pdev,
}
}

+ if (of_node_cmp(child->name, "onenand") == 0) {
+ /* Warn about older DT blobs with no compatible property */
+ if (!of_property_read_bool(child, "compatible")) {
+ dev_warn(&pdev->dev,
+ "Incompatible OneNAND node: missing compatible");
+ ret = -EINVAL;
+ goto err;
+ }
+ }
+
if (of_device_is_compatible(child, "ti,omap2-nand")) {
/* NAND specific setup */
val = 8;
@@ -2189,11 +2269,7 @@ static void gpmc_probe_dt_children(struct platform_device *pdev)
if (!child->name)
continue;

- if (of_node_cmp(child->name, "onenand") == 0)
- ret = gpmc_probe_onenand_child(pdev, child);
- else
- ret = gpmc_probe_generic_child(pdev, child);
-
+ ret = gpmc_probe_generic_child(pdev, child);
if (ret) {
dev_err(&pdev->dev, "failed to probe DT child '%s': %d\n",
child->name, ret);
diff --git a/drivers/mtd/onenand/Kconfig b/drivers/mtd/onenand/Kconfig
index aaeb30458139..9dc15748947b 100644
--- a/drivers/mtd/onenand/Kconfig
+++ b/drivers/mtd/onenand/Kconfig
@@ -25,9 +25,11 @@ config MTD_ONENAND_GENERIC
config MTD_ONENAND_OMAP2
tristate "OneNAND on OMAP2/OMAP3 support"
depends on ARCH_OMAP2 || ARCH_OMAP3
+ depends on OF || COMPILE_TEST
help
- Support for a OneNAND flash device connected to an OMAP2/OMAP3 CPU
+ Support for a OneNAND flash device connected to an OMAP2/OMAP3 SoC
via the GPMC memory controller.
+ Enable dmaengine and gpiolib for better performance.

config MTD_ONENAND_SAMSUNG
tristate "OneNAND on Samsung SOC controller support"
diff --git a/drivers/mtd/onenand/omap2.c b/drivers/mtd/onenand/omap2.c
index 1cd78a076759..2ce73fb6da1c 100644
--- a/drivers/mtd/onenand/omap2.c
+++ b/drivers/mtd/onenand/omap2.c
@@ -28,6 +28,8 @@
#include <linux/mtd/mtd.h>
#include <linux/mtd/onenand.h>
#include <linux/mtd/partitions.h>
+#include <linux/of_device.h>
+#include <linux/omap-gpmc.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
@@ -35,10 +37,9 @@
#include <linux/dmaengine.h>
#include <linux/io.h>
#include <linux/slab.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>

#include <asm/mach/flash.h>
-#include <linux/platform_data/mtd-onenand-omap2.h>

#define DRIVER_NAME "omap2-onenand"

@@ -48,15 +49,12 @@ struct omap2_onenand {
struct platform_device *pdev;
int gpmc_cs;
unsigned long phys_base;
- unsigned int mem_size;
- int gpio_irq;
+ struct gpio_desc *int_gpiod;
struct mtd_info mtd;
struct onenand_chip onenand;
struct completion irq_done;
struct completion dma_done;
struct dma_chan *dma_chan;
- int freq;
- int (*setup)(void __iomem *base, int *freq_ptr);
};

static void omap2_onenand_dma_complete_func(void *completion)
@@ -84,6 +82,65 @@ static inline void write_reg(struct omap2_onenand *c, unsigned short value,
writew(value, c->onenand.base + reg);
}

+static int omap2_onenand_set_cfg(struct omap2_onenand *c,
+ bool sr, bool sw,
+ int latency, int burst_len)
+{
+ unsigned short reg = ONENAND_SYS_CFG1_RDY | ONENAND_SYS_CFG1_INT;
+
+ reg |= latency << ONENAND_SYS_CFG1_BRL_SHIFT;
+
+ switch (burst_len) {
+ case 0: /* continuous */
+ break;
+ case 4:
+ reg |= ONENAND_SYS_CFG1_BL_4;
+ break;
+ case 8:
+ reg |= ONENAND_SYS_CFG1_BL_8;
+ break;
+ case 16:
+ reg |= ONENAND_SYS_CFG1_BL_16;
+ break;
+ case 32:
+ reg |= ONENAND_SYS_CFG1_BL_32;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (latency > 5)
+ reg |= ONENAND_SYS_CFG1_HF;
+ if (latency > 7)
+ reg |= ONENAND_SYS_CFG1_VHF;
+ if (sr)
+ reg |= ONENAND_SYS_CFG1_SYNC_READ;
+ if (sw)
+ reg |= ONENAND_SYS_CFG1_SYNC_WRITE;
+
+ write_reg(c, reg, ONENAND_REG_SYS_CFG1);
+
+ return 0;
+}
+
+static int omap2_onenand_get_freq(int ver)
+{
+ switch ((ver >> 4) & 0xf) {
+ case 0:
+ return 40;
+ case 1:
+ return 54;
+ case 2:
+ return 66;
+ case 3:
+ return 83;
+ case 4:
+ return 104;
+ }
+
+ return -EINVAL;
+}
+
static void wait_err(char *msg, int state, unsigned int ctrl, unsigned int intr)
{
printk(KERN_ERR "onenand_wait: %s! state %d ctrl 0x%04x intr 0x%04x\n",
@@ -152,12 +209,12 @@ static int omap2_onenand_wait(struct mtd_info *mtd, int state)
}

reinit_completion(&c->irq_done);
- result = gpio_get_value(c->gpio_irq);
+ result = gpiod_get_value(c->int_gpiod);
if (result < 0) {
ctrl = read_reg(c, ONENAND_REG_CTRL_STATUS);
intr = read_reg(c, ONENAND_REG_INTERRUPT);
wait_err("gpio error", state, ctrl, intr);
- return -EIO;
+ return result;
} else if (result == 0) {
int retry_cnt = 0;
retry:
@@ -431,8 +488,6 @@ static int omap2_onenand_write_bufferram(struct mtd_info *mtd, int area,
return 0;
}

-static struct platform_driver omap2_onenand_driver;
-
static void omap2_onenand_shutdown(struct platform_device *pdev)
{
struct omap2_onenand *c = dev_get_drvdata(&pdev->dev);
@@ -446,105 +501,117 @@ static void omap2_onenand_shutdown(struct platform_device *pdev)

static int omap2_onenand_probe(struct platform_device *pdev)
{
+ u32 val;
dma_cap_mask_t mask;
- struct omap_onenand_platform_data *pdata;
- struct omap2_onenand *c;
- struct onenand_chip *this;
- int r;
+ int freq, latency, r;
struct resource *res;
+ struct omap2_onenand *c;
+ struct gpmc_onenand_info info;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(dev, "error getting memory resource\n");
+ return -EINVAL;
+ }

- pdata = dev_get_platdata(&pdev->dev);
- if (pdata == NULL) {
- dev_err(&pdev->dev, "platform data missing\n");
- return -ENODEV;
+ r = of_property_read_u32(np, "reg", &val);
+ if (r) {
+ dev_err(dev, "reg not found in DT\n");
+ return r;
}

- c = kzalloc(sizeof(struct omap2_onenand), GFP_KERNEL);
+ c = devm_kzalloc(dev, sizeof(struct omap2_onenand), GFP_KERNEL);
if (!c)
return -ENOMEM;

init_completion(&c->irq_done);
init_completion(&c->dma_done);
- c->gpmc_cs = pdata->cs;
- c->gpio_irq = pdata->gpio_irq;
- if (pdata->dma_channel < 0) {
- /* if -1, don't use DMA */
- c->gpio_irq = 0;
- }
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (res == NULL) {
- r = -EINVAL;
- dev_err(&pdev->dev, "error getting memory resource\n");
- goto err_kfree;
- }
-
+ c->gpmc_cs = val;
c->phys_base = res->start;
- c->mem_size = resource_size(res);
-
- if (request_mem_region(c->phys_base, c->mem_size,
- pdev->dev.driver->name) == NULL) {
- dev_err(&pdev->dev, "Cannot reserve memory region at 0x%08lx, size: 0x%x\n",
- c->phys_base, c->mem_size);
- r = -EBUSY;
- goto err_kfree;
- }
- c->onenand.base = ioremap(c->phys_base, c->mem_size);
- if (c->onenand.base == NULL) {
- r = -ENOMEM;
- goto err_release_mem_region;
- }

- if (pdata->onenand_setup != NULL) {
- r = pdata->onenand_setup(c->onenand.base, &c->freq);
- if (r < 0) {
- dev_err(&pdev->dev, "Onenand platform setup failed: "
- "%d\n", r);
- goto err_iounmap;
- }
- c->setup = pdata->onenand_setup;
+ c->onenand.base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(c->onenand.base)) {
+ dev_err(dev, "Cannot reserve memory region at 0x%08x, size: 0x%x\n",
+ res->start, resource_size(res));
+ return PTR_ERR(c->onenand.base);
}

- if (c->gpio_irq) {
- if ((r = gpio_request(c->gpio_irq, "OneNAND irq")) < 0) {
- dev_err(&pdev->dev, "Failed to request GPIO%d for "
- "OneNAND\n", c->gpio_irq);
- goto err_iounmap;
- }
- gpio_direction_input(c->gpio_irq);
+ c->int_gpiod = devm_gpiod_get_optional(dev, "int", GPIOD_IN);
+ if (IS_ERR(c->int_gpiod)) {
+ r = PTR_ERR(c->int_gpiod);
+ /* Just try again if this happens */
+ if (r != -EPROBE_DEFER)
+ dev_err(dev, "error getting gpio: %d\n", r);
+ return r;
+ }

- if ((r = request_irq(gpio_to_irq(c->gpio_irq),
- omap2_onenand_interrupt, IRQF_TRIGGER_RISING,
- pdev->dev.driver->name, c)) < 0)
- goto err_release_gpio;
+ if (c->int_gpiod) {
+ r = devm_request_irq(dev, gpiod_to_irq(c->int_gpiod),
+ omap2_onenand_interrupt,
+ IRQF_TRIGGER_RISING, "onenand", c);
+ if (r)
+ return r;

- this->wait = omap2_onenand_wait;
+ c->onenand.wait = omap2_onenand_wait;
}

dma_cap_zero(mask);
dma_cap_set(DMA_MEMCPY, mask);

c->dma_chan = dma_request_channel(mask, NULL, NULL);
-
- dev_info(&pdev->dev, "initializing on CS%d, phys base 0x%08lx, virtual "
- "base %p, freq %d MHz, %s mode\n", c->gpmc_cs, c->phys_base,
- c->onenand.base, c->freq, c->dma_chan ? "DMA" : "PIO");
+ if (c->dma_chan) {
+ c->onenand.read_bufferram = omap2_onenand_read_bufferram;
+ c->onenand.write_bufferram = omap2_onenand_write_bufferram;
+ }

c->pdev = pdev;
c->mtd.priv = &c->onenand;
+ c->mtd.dev.parent = dev;
+ mtd_set_of_node(&c->mtd, dev->of_node);

- c->mtd.dev.parent = &pdev->dev;
- mtd_set_of_node(&c->mtd, pdata->of_node);
-
- this = &c->onenand;
- if (c->dma_chan) {
- this->read_bufferram = omap2_onenand_read_bufferram;
- this->write_bufferram = omap2_onenand_write_bufferram;
- }
+ dev_info(dev, "initializing on CS%d (0x%08lx), va %p, %s mode\n",
+ c->gpmc_cs, c->phys_base, c->onenand.base,
+ c->dma_chan ? "DMA" : "PIO");

if ((r = onenand_scan(&c->mtd, 1)) < 0)
goto err_release_dma;

+ freq = omap2_onenand_get_freq(c->onenand.version_id);
+ if (freq > 0) {
+ switch (freq) {
+ case 104:
+ latency = 7;
+ break;
+ case 83:
+ latency = 6;
+ break;
+ case 66:
+ latency = 5;
+ break;
+ case 56:
+ latency = 4;
+ break;
+ default: /* 40 MHz or lower */
+ latency = 3;
+ break;
+ }
+
+ r = gpmc_omap_onenand_set_timings(dev, c->gpmc_cs,
+ freq, latency, &info);
+ if (r)
+ goto err_release_onenand;
+
+ r = omap2_onenand_set_cfg(c, info.sync_read, info.sync_write,
+ latency, info.burst_len);
+ if (r)
+ goto err_release_onenand;
+
+ if (info.sync_read || info.sync_write)
+ dev_info(dev, "optimized timings for %d MHz\n", freq);
+ }
+
r = mtd_device_register(&c->mtd, NULL, 0);
if (r)
goto err_release_onenand;
@@ -558,17 +625,6 @@ static int omap2_onenand_probe(struct platform_device *pdev)
err_release_dma:
if (c->dma_chan)
dma_release_channel(c->dma_chan);
- if (c->gpio_irq)
- free_irq(gpio_to_irq(c->gpio_irq), c);
-err_release_gpio:
- if (c->gpio_irq)
- gpio_free(c->gpio_irq);
-err_iounmap:
- iounmap(c->onenand.base);
-err_release_mem_region:
- release_mem_region(c->phys_base, c->mem_size);
-err_kfree:
- kfree(c);

return r;
}
@@ -581,23 +637,23 @@ static int omap2_onenand_remove(struct platform_device *pdev)
if (c->dma_chan)
dma_release_channel(c->dma_chan);
omap2_onenand_shutdown(pdev);
- if (c->gpio_irq) {
- free_irq(gpio_to_irq(c->gpio_irq), c);
- gpio_free(c->gpio_irq);
- }
- iounmap(c->onenand.base);
- release_mem_region(c->phys_base, c->mem_size);
- kfree(c);

return 0;
}

+static const struct of_device_id omap2_onenand_id_table[] = {
+ { .compatible = "ti,omap2-onenand", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, omap2_onenand_id_table);
+
static struct platform_driver omap2_onenand_driver = {
.probe = omap2_onenand_probe,
.remove = omap2_onenand_remove,
.shutdown = omap2_onenand_shutdown,
.driver = {
.name = DRIVER_NAME,
+ .of_match_table = omap2_onenand_id_table,
},
};

diff --git a/include/linux/omap-gpmc.h b/include/linux/omap-gpmc.h
index edfa280c3d56..053feb41510a 100644
--- a/include/linux/omap-gpmc.h
+++ b/include/linux/omap-gpmc.h
@@ -25,15 +25,43 @@ struct gpmc_nand_ops {

struct gpmc_nand_regs;

+struct gpmc_onenand_info {
+ bool sync_read;
+ bool sync_write;
+ int burst_len;
+};
+
#if IS_ENABLED(CONFIG_OMAP_GPMC)
struct gpmc_nand_ops *gpmc_omap_get_nand_ops(struct gpmc_nand_regs *regs,
int cs);
+/**
+ * gpmc_omap_onenand_set_timings - set optimized sync timings.
+ * @cs: Chip Select Region
+ * @freq: Chip frequency
+ * @latency: Burst latency cycle count
+ * @info: Structure describing parameters used
+ *
+ * Sets optimized timings for the @cs region based on @freq and @latency.
+ * Updates the @info structure based on the GPMC settings.
+ */
+int gpmc_omap_onenand_set_timings(struct device *dev, int cs, int freq,
+ int latency,
+ struct gpmc_onenand_info *info);
+
#else
static inline struct gpmc_nand_ops *gpmc_omap_get_nand_ops(struct gpmc_nand_regs *regs,
int cs)
{
return NULL;
}
+
+static inline
+int gpmc_omap_onenand_set_timings(struct device *dev, int cs, int freq,
+ int latency,
+ struct gpmc_onenand_info *info)
+{
+ return -EINVAL;
+}
#endif /* CONFIG_OMAP_GPMC */

extern int gpmc_calc_timings(struct gpmc_timings *gpmc_t,