[PATCH v3 5/7] nvmem: imx-ocotp: Add i.MX7D timing write clock setup support

From: Bryan O'Donoghue
Date: Mon Oct 09 2017 - 10:12:23 EST


This patch adds logic to correctly setup the write timing parameters
when blowing an OTP fuse for the i.MX7S/D.

Fixes: 0642bac7da42 ("nvmem: imx-ocotp: add write support")

Signed-off-by: Bryan O'Donoghue <pure.logic@xxxxxxxxxxxxxxxxx>
---
drivers/nvmem/imx-ocotp.c | 63 ++++++++++++++++++++++++++++++++++++++---------
1 file changed, 52 insertions(+), 11 deletions(-)

diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c
index 2645ee3..f80aee9 100644
--- a/drivers/nvmem/imx-ocotp.c
+++ b/drivers/nvmem/imx-ocotp.c
@@ -51,16 +51,12 @@
#define IMX_OCOTP_BM_CTRL_REL_SHADOWS 0x00000400

#define DEF_RELAX 20 /* > 16.5ns */
+#define DEF_FSOURCE 1001
#define IMX_OCOTP_WR_UNLOCK 0x3E770000
#define IMX_OCOTP_READ_LOCKED_VAL 0xBADABADA

static DEFINE_MUTEX(ocotp_mutex);

-struct ocotp_params {
- unsigned int nregs;
- unsigned int bank_address_words;
-};
-
struct ocotp_priv {
struct device *dev;
struct clk *clk;
@@ -69,6 +65,12 @@ struct ocotp_priv {
struct nvmem_config *config;
};

+struct ocotp_params {
+ unsigned int nregs;
+ unsigned int bank_address_words;
+ void (*set_timing)(struct ocotp_priv *priv);
+};
+
static int imx_ocotp_wait_for_busy(void __iomem *base, u32 flags)
{
int count;
@@ -193,6 +195,25 @@ static void imx_ocotp_set_imx6_timing(struct ocotp_priv *priv)
writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
}

+static void imx_ocotp_set_imx7_timing(struct ocotp_priv *priv)
+{
+ unsigned long clk_rate = 0;
+ unsigned long fsource, strobe_prog;
+ u32 timing = 0;
+
+ /* i.MX 7Solo Applications Processor Reference Manual, Rev. 0.1
+ * 6.4.3.3
+ */
+ clk_rate = clk_get_rate(priv->clk);
+ fsource = DIV_ROUND_UP(((clk_rate / 1000) * DEF_FSOURCE), 1000000) + 1;
+ strobe_prog = ((clk_rate * 10) / 1000000) + 1;
+
+ timing = strobe_prog & 0x00000FFF;
+ timing |= (fsource << 12) & 0x000FF000;
+
+ writel(timing, priv->base + IMX_OCOTP_ADDR_TIMING);
+}
+
static int imx_ocotp_write(void *context, unsigned int offset, void *val,
size_t bytes)
{
@@ -219,7 +240,7 @@ static int imx_ocotp_write(void *context, unsigned int offset, void *val,
}

/* Setup the write timing values */
- imx_ocotp_set_imx6_timing(priv);
+ priv->params->set_timing(priv);

/* 47.3.1.3.2
* Check that HW_OCOTP_CTRL[BUSY] and HW_OCOTP_CTRL[ERROR] are clear.
@@ -372,11 +393,31 @@ static struct nvmem_config imx_ocotp_nvmem_config = {
};

static const struct ocotp_params params[] = {
- { .nregs = 128, .bank_address_words = 0 },
- { .nregs = 64, .bank_address_words = 0 },
- { .nregs = 128, .bank_address_words = 0 },
- { .nregs = 128, .bank_address_words = 0 },
- { .nregs = 64, .bank_address_words = 4 },
+ {
+ .nregs = 128,
+ .bank_address_words = 0,
+ .set_timing = imx_ocotp_set_imx6_timing,
+ },
+ {
+ .nregs = 64,
+ .bank_address_words = 0,
+ .set_timing = imx_ocotp_set_imx6_timing,
+ },
+ {
+ .nregs = 128,
+ .bank_address_words = 0,
+ .set_timing = imx_ocotp_set_imx6_timing,
+ },
+ {
+ .nregs = 128,
+ .bank_address_words = 0,
+ .set_timing = imx_ocotp_set_imx6_timing,
+ },
+ {
+ .nregs = 64,
+ .bank_address_words = 4,
+ .set_timing = imx_ocotp_set_imx7_timing,
+ },
};

static const struct of_device_id imx_ocotp_dt_ids[] = {
--
2.7.4