ARM: OMAP2+: onenand: refactor for clarity
authorAfzal Mohammed <afzal@ti.com>
Tue, 5 Jun 2012 04:41:48 +0000 (10:11 +0530)
committerAfzal Mohammed <afzal@ti.com>
Mon, 15 Oct 2012 09:10:26 +0000 (14:40 +0530)
Refactor set_async_mode & set_sync_mode functions to
separate out timing calculation & actual configuration
(GPMC & OneNAND side).

Thanks to Jon for his suggestions.

Signed-off-by: Afzal Mohammed <afzal@ti.com>
Reviewed-by: Jon Hunter <jon-hunter@ti.com>
arch/arm/mach-omap2/gpmc-onenand.c

index 916716e1da3bf6644799d7969a3d9924b1ed94e9..29d391b273fcccaf50a6aa76f7529f955b9ecae4 100644 (file)
@@ -16,6 +16,7 @@
 #include <linux/mtd/onenand_regs.h>
 #include <linux/io.h>
 #include <linux/platform_data/mtd-onenand-omap2.h>
+#include <linux/err.h>
 
 #include <asm/mach/flash.h>
 
 
 #define        ONENAND_IO_SIZE SZ_128K
 
+#define        ONENAND_FLAG_SYNCREAD   (1 << 0)
+#define        ONENAND_FLAG_SYNCWRITE  (1 << 1)
+#define        ONENAND_FLAG_HF         (1 << 2)
+#define        ONENAND_FLAG_VHF        (1 << 3)
+
+static unsigned onenand_flags;
+static unsigned latency;
+static int fclk_offset;
+
 static struct omap_onenand_platform_data *gpmc_onenand_data;
 
 static struct resource gpmc_onenand_resource = {
@@ -38,11 +48,9 @@ static struct platform_device gpmc_onenand_device = {
        .resource       = &gpmc_onenand_resource,
 };
 
-static int omap2_onenand_set_async_mode(int cs, void __iomem *onenand_base)
+static struct gpmc_timings omap2_onenand_calc_async_timings(void)
 {
        struct gpmc_timings t;
-       u32 reg;
-       int err;
 
        const int t_cer = 15;
        const int t_avdp = 12;
@@ -55,11 +63,6 @@ static int omap2_onenand_set_async_mode(int cs, void __iomem *onenand_base)
        const int t_wpl = 40;
        const int t_wph = 30;
 
-       /* Ensure sync read and sync write are disabled */
-       reg = readw(onenand_base + ONENAND_REG_SYS_CFG1);
-       reg &= ~ONENAND_SYS_CFG1_SYNC_READ & ~ONENAND_SYS_CFG1_SYNC_WRITE;
-       writew(reg, onenand_base + ONENAND_REG_SYS_CFG1);
-
        memset(&t, 0, sizeof(t));
        t.sync_clk = 0;
        t.cs_on = 0;
@@ -86,25 +89,30 @@ static int omap2_onenand_set_async_mode(int cs, void __iomem *onenand_base)
        t.cs_wr_off = t.we_off + gpmc_round_ns_to_ticks(t_wph);
        t.wr_cycle  = t.cs_wr_off + gpmc_round_ns_to_ticks(t_cez);
 
+       return t;
+}
+
+static int gpmc_set_async_mode(int cs, struct gpmc_timings *t)
+{
        /* Configure GPMC for asynchronous read */
        gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1,
                          GPMC_CONFIG1_DEVICESIZE_16 |
                          GPMC_CONFIG1_MUXADDDATA);
 
-       err = gpmc_cs_set_timings(cs, &t);
-       if (err)
-               return err;
+       return gpmc_cs_set_timings(cs, t);
+}
+
+static void omap2_onenand_set_async_mode(void __iomem *onenand_base)
+{
+       u32 reg;
 
        /* Ensure sync read and sync write are disabled */
        reg = readw(onenand_base + ONENAND_REG_SYS_CFG1);
        reg &= ~ONENAND_SYS_CFG1_SYNC_READ & ~ONENAND_SYS_CFG1_SYNC_WRITE;
        writew(reg, onenand_base + ONENAND_REG_SYS_CFG1);
-
-       return 0;
 }
 
-static void set_onenand_cfg(void __iomem *onenand_base, int latency,
-                               int sync_read, int sync_write, int hf, int vhf)
+static void set_onenand_cfg(void __iomem *onenand_base)
 {
        u32 reg;
 
@@ -112,19 +120,19 @@ static void set_onenand_cfg(void __iomem *onenand_base, int latency,
        reg &= ~((0x7 << ONENAND_SYS_CFG1_BRL_SHIFT) | (0x7 << 9));
        reg |=  (latency << ONENAND_SYS_CFG1_BRL_SHIFT) |
                ONENAND_SYS_CFG1_BL_16;
-       if (sync_read)
+       if (onenand_flags & ONENAND_FLAG_SYNCREAD)
                reg |= ONENAND_SYS_CFG1_SYNC_READ;
        else
                reg &= ~ONENAND_SYS_CFG1_SYNC_READ;
-       if (sync_write)
+       if (onenand_flags & ONENAND_FLAG_SYNCWRITE)
                reg |= ONENAND_SYS_CFG1_SYNC_WRITE;
        else
                reg &= ~ONENAND_SYS_CFG1_SYNC_WRITE;
-       if (hf)
+       if (onenand_flags & ONENAND_FLAG_HF)
                reg |= ONENAND_SYS_CFG1_HF;
        else
                reg &= ~ONENAND_SYS_CFG1_HF;
-       if (vhf)
+       if (onenand_flags & ONENAND_FLAG_VHF)
                reg |= ONENAND_SYS_CFG1_VHF;
        else
                reg &= ~ONENAND_SYS_CFG1_VHF;
@@ -172,9 +180,9 @@ static int omap2_onenand_get_freq(struct omap_onenand_platform_data *cfg,
        return freq;
 }
 
-static int omap2_onenand_set_sync_mode(struct omap_onenand_platform_data *cfg,
-                                       void __iomem *onenand_base,
-                                       int *freq_ptr)
+static struct gpmc_timings
+omap2_onenand_calc_sync_timings(struct omap_onenand_platform_data *cfg,
+                               int freq, bool clk_dep)
 {
        struct gpmc_timings t;
        const int t_cer  = 15;
@@ -184,29 +192,15 @@ static int omap2_onenand_set_sync_mode(struct omap_onenand_platform_data *cfg,
        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;
-       int div, fclk_offset_ns, fclk_offset, gpmc_clk_ns, latency;
-       int first_time = 0, hf = 0, vhf = 0, sync_read = 0, sync_write = 0;
-       int err, ticks_cez;
-       int cs = cfg->cs, freq = *freq_ptr;
        u32 reg;
-       bool clk_dep = false;
-
-       if (cfg->flags & ONENAND_SYNC_READ) {
-               sync_read = 1;
-       } else if (cfg->flags & ONENAND_SYNC_READWRITE) {
-               sync_read = 1;
-               sync_write = 1;
-       } else
-               return omap2_onenand_set_async_mode(cs, onenand_base);
+       int div, fclk_offset_ns, gpmc_clk_ns;
+       int ticks_cez;
+       int cs = cfg->cs;
 
-       if (!freq) {
-               /* Very first call freq is not known */
-               err = omap2_onenand_set_async_mode(cs, onenand_base);
-               if (err)
-                       return err;
-               freq = omap2_onenand_get_freq(cfg, onenand_base, &clk_dep);
-               first_time = 1;
-       }
+       if (cfg->flags & ONENAND_SYNC_READ)
+               onenand_flags = ONENAND_FLAG_SYNCREAD;
+       else if (cfg->flags & ONENAND_SYNC_READWRITE)
+               onenand_flags = ONENAND_FLAG_SYNCREAD | ONENAND_FLAG_SYNCWRITE;
 
        switch (freq) {
        case 104:
@@ -244,19 +238,23 @@ static int omap2_onenand_set_sync_mode(struct omap_onenand_platform_data *cfg,
                t_ach   = 9;
                t_aavdh = 7;
                t_rdyo  = 15;
-               sync_write = 0;
+               onenand_flags &= ~ONENAND_FLAG_SYNCWRITE;
                break;
        }
 
        div = gpmc_cs_calc_divider(cs, min_gpmc_clk_period);
        gpmc_clk_ns = gpmc_ticks_to_ns(div);
        if (gpmc_clk_ns < 15) /* >66Mhz */
-               hf = 1;
+               onenand_flags |= ONENAND_FLAG_HF;
+       else
+               onenand_flags &= ~ONENAND_FLAG_HF;
        if (gpmc_clk_ns < 12) /* >83Mhz */
-               vhf = 1;
-       if (vhf)
+               onenand_flags |= ONENAND_FLAG_VHF;
+       else
+               onenand_flags &= ~ONENAND_FLAG_VHF;
+       if (onenand_flags & ONENAND_FLAG_VHF)
                latency = 8;
-       else if (hf)
+       else if (onenand_flags & ONENAND_FLAG_HF)
                latency = 6;
        else if (gpmc_clk_ns >= 25) /* 40 MHz*/
                latency = 3;
@@ -279,9 +277,8 @@ static int omap2_onenand_set_sync_mode(struct omap_onenand_platform_data *cfg,
                }
        }
 
-       if (first_time)
-               set_onenand_cfg(onenand_base, latency,
-                                       sync_read, sync_write, hf, vhf);
+       /* Set synchronous read timings */
+       memset(&t, 0, sizeof(t));
 
        if (div == 1) {
                reg = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG2);
@@ -307,8 +304,6 @@ static int omap2_onenand_set_sync_mode(struct omap_onenand_platform_data *cfg,
                gpmc_cs_write_reg(cs, GPMC_CS_CONFIG4, reg);
        }
 
-       /* Set synchronous read timings */
-       memset(&t, 0, sizeof(t));
        t.sync_clk = min_gpmc_clk_period;
        t.cs_on = 0;
        t.adv_on = 0;
@@ -330,7 +325,7 @@ static int omap2_onenand_set_sync_mode(struct omap_onenand_platform_data *cfg,
                     ticks_cez);
 
        /* Write */
-       if (sync_write) {
+       if (onenand_flags & ONENAND_FLAG_SYNCWRITE) {
                t.adv_wr_off = t.adv_rd_off;
                t.we_on  = 0;
                t.we_off = t.cs_rd_off;
@@ -355,6 +350,14 @@ static int omap2_onenand_set_sync_mode(struct omap_onenand_platform_data *cfg,
                }
        }
 
+       return t;
+}
+
+static int gpmc_set_sync_mode(int cs, struct gpmc_timings *t)
+{
+       unsigned sync_read = onenand_flags & ONENAND_FLAG_SYNCREAD;
+       unsigned sync_write = onenand_flags & ONENAND_FLAG_SYNCWRITE;
+
        /* Configure GPMC for synchronous read */
        gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1,
                          GPMC_CONFIG1_WRAPBURST_SUPP |
@@ -371,11 +374,47 @@ static int omap2_onenand_set_sync_mode(struct omap_onenand_platform_data *cfg,
                          GPMC_CONFIG1_DEVICETYPE_NOR |
                          GPMC_CONFIG1_MUXADDDATA);
 
-       err = gpmc_cs_set_timings(cs, &t);
-       if (err)
-               return err;
+       return gpmc_cs_set_timings(cs, t);
+}
+
+static int omap2_onenand_setup_async(void __iomem *onenand_base)
+{
+       struct gpmc_timings t;
+       int ret;
+
+       omap2_onenand_set_async_mode(onenand_base);
+
+       t = omap2_onenand_calc_async_timings();
+
+       ret = gpmc_set_async_mode(gpmc_onenand_data->cs, &t);
+       if (IS_ERR_VALUE(ret))
+               return ret;
+
+       omap2_onenand_set_async_mode(onenand_base);
+
+       return 0;
+}
+
+static int omap2_onenand_setup_sync(void __iomem *onenand_base, int *freq_ptr)
+{
+       int ret, freq = *freq_ptr;
+       struct gpmc_timings t;
+       bool clk_dep = false;
+
+       if (!freq) {
+               /* Very first call freq is not known */
+               freq = omap2_onenand_get_freq(gpmc_onenand_data,
+                                               onenand_base, &clk_dep);
+               set_onenand_cfg(onenand_base);
+       }
+
+       t = omap2_onenand_calc_sync_timings(gpmc_onenand_data, freq, clk_dep);
 
-       set_onenand_cfg(onenand_base, latency, sync_read, sync_write, hf, vhf);
+       ret = gpmc_set_sync_mode(gpmc_onenand_data->cs, &t);
+       if (IS_ERR_VALUE(ret))
+               return ret;
+
+       set_onenand_cfg(onenand_base);
 
        *freq_ptr = freq;
 
@@ -385,15 +424,22 @@ static int omap2_onenand_set_sync_mode(struct omap_onenand_platform_data *cfg,
 static int gpmc_onenand_setup(void __iomem *onenand_base, int *freq_ptr)
 {
        struct device *dev = &gpmc_onenand_device.dev;
+       unsigned l = ONENAND_SYNC_READ | ONENAND_SYNC_READWRITE;
+       int ret;
 
-       /* Set sync timings in GPMC */
-       if (omap2_onenand_set_sync_mode(gpmc_onenand_data, onenand_base,
-                       freq_ptr) < 0) {
-               dev_err(dev, "Unable to set synchronous mode\n");
-               return -EINVAL;
+       ret = omap2_onenand_setup_async(onenand_base);
+       if (ret) {
+               dev_err(dev, "unable to set to async mode\n");
+               return ret;
        }
 
-       return 0;
+       if (!(gpmc_onenand_data->flags & l))
+               return 0;
+
+       ret = omap2_onenand_setup_sync(onenand_base, freq_ptr);
+       if (ret)
+               dev_err(dev, "unable to set to sync mode\n");
+       return ret;
 }
 
 void __init gpmc_onenand_init(struct omap_onenand_platform_data *_onenand_data)