@@ -69,15 +69,15 @@
#define ACR_SSTROBE_MASK BIT(31)
#define ASIZE_16BIT 1
-#define CONFIG_MASK (TA(TA_MAX) | \
- RHOLD(RHOLD_MAX) | \
- RSTROBE(RSTROBE_MAX) | \
- RSETUP(RSETUP_MAX) | \
- WHOLD(WHOLD_MAX) | \
- WSTROBE(WSTROBE_MAX) | \
- WSETUP(WSETUP_MAX) | \
- EW(EW_MAX) | SSTROBE(SSTROBE_MAX) | \
- ASIZE_MAX)
+#define TIMINGS_MASK (TA(TA_MAX) | \
+ RHOLD(RHOLD_MAX) | \
+ RSTROBE(RSTROBE_MAX) | \
+ RSETUP(RSETUP_MAX) | \
+ WHOLD(WHOLD_MAX) | \
+ WSTROBE(WSTROBE_MAX) | \
+ WSETUP(WSETUP_MAX))
+
+#define CONFIG_MASK (EW(EW_MAX) | SSTROBE(SSTROBE_MAX) | ASIZE_MAX)
/**
* struct aemif_cs_data: structure to hold cs parameters
@@ -107,6 +107,27 @@ struct aemif_cs_data {
u8 asize;
};
+/**
+ * struct aemif_cs_timing: structure to hold cs timing configuration
+ * values are expressed in number of clock cycles - 1
+ * @ta: minimum turn around time
+ * @rhold read hold width
+ * @rstrobe read strobe width
+ * @rsetup read setup width
+ * @whold write hold width
+ * @wstrobe write strobe width
+ * @wsetup write setup width
+ */
+struct aemif_cs_timings {
+ u32 ta;
+ u32 rhold;
+ u32 rstrobe;
+ u32 rsetup;
+ u32 whold;
+ u32 wstrobe;
+ u32 wsetup;
+};
+
/**
* struct aemif_device: structure to hold device data
* @base: base address of AEMIF registers
@@ -125,6 +146,44 @@ struct aemif_device {
struct aemif_cs_data cs_data[NUM_CS];
};
+/**
+ * aemif_set_cs_timings - Set the timing configuration of a given chip select.
+ * @aemif: aemif device to configure
+ * @cs: index of the chip select to configure.
+ * @timings: timings configuration to set
+ *
+ * Returns 0 on success, else negative errno.
+ */
+static int aemif_set_cs_timings(struct aemif_device *aemif, u8 cs, struct aemif_cs_timings *timings)
+{
+ unsigned int offset;
+ u32 val, set;
+
+ if (!timings || !aemif)
+ return -EINVAL;
+
+ if (cs > aemif->num_cs)
+ return -EINVAL;
+
+ if (timings->ta > TA_MAX || timings->rhold > RHOLD_MAX || timings->rstrobe > RSTROBE_MAX ||
+ timings->rsetup > RSETUP_MAX || timings->whold > WHOLD_MAX ||
+ timings->wstrobe > WSTROBE_MAX || timings->wsetup > WSETUP_MAX)
+ return -EINVAL;
+
+ set = TA(timings->ta) | RHOLD(timings->rhold) | RSTROBE(timings->rstrobe) |
+ RSETUP(timings->rsetup) | WHOLD(timings->whold) |
+ WSTROBE(timings->wstrobe) | WSETUP(timings->wsetup);
+
+ offset = A1CR_OFFSET + cs * 4;
+
+ val = readl(aemif->base + offset);
+ val &= ~TIMINGS_MASK;
+ val |= set;
+ writel(val, aemif->base + offset);
+
+ return 0;
+}
+
/**
* aemif_calc_rate - calculate timing data.
* @pdev: platform device to calculate for
@@ -149,10 +208,6 @@ static int aemif_calc_rate(struct platform_device *pdev, int wanted,
if (result < 0)
result = 0;
- /* ... But configuring tighter timings is not an option. */
- else if (result > max)
- result = -EINVAL;
-
return result;
}
@@ -174,32 +229,22 @@ static int aemif_config_abus(struct platform_device *pdev, int csnum)
{
struct aemif_device *aemif = platform_get_drvdata(pdev);
struct aemif_cs_data *data = &aemif->cs_data[csnum];
- int ta, rhold, rstrobe, rsetup, whold, wstrobe, wsetup;
unsigned long clk_rate = aemif->clk_rate;
+ struct aemif_cs_timings timings;
unsigned offset;
u32 set, val;
offset = A1CR_OFFSET + (data->cs - aemif->cs_offset) * 4;
- ta = aemif_calc_rate(pdev, data->ta, clk_rate, TA_MAX);
- rhold = aemif_calc_rate(pdev, data->rhold, clk_rate, RHOLD_MAX);
- rstrobe = aemif_calc_rate(pdev, data->rstrobe, clk_rate, RSTROBE_MAX);
- rsetup = aemif_calc_rate(pdev, data->rsetup, clk_rate, RSETUP_MAX);
- whold = aemif_calc_rate(pdev, data->whold, clk_rate, WHOLD_MAX);
- wstrobe = aemif_calc_rate(pdev, data->wstrobe, clk_rate, WSTROBE_MAX);
- wsetup = aemif_calc_rate(pdev, data->wsetup, clk_rate, WSETUP_MAX);
-
- if (ta < 0 || rhold < 0 || rstrobe < 0 || rsetup < 0 ||
- whold < 0 || wstrobe < 0 || wsetup < 0) {
- dev_err(&pdev->dev, "%s: cannot get suitable timings\n",
- __func__);
- return -EINVAL;
- }
-
- set = TA(ta) | RHOLD(rhold) | RSTROBE(rstrobe) | RSETUP(rsetup) |
- WHOLD(whold) | WSTROBE(wstrobe) | WSETUP(wsetup);
+ timings.ta = aemif_calc_rate(pdev, data->ta, clk_rate, TA_MAX);
+ timings.rhold = aemif_calc_rate(pdev, data->rhold, clk_rate, RHOLD_MAX);
+ timings.rstrobe = aemif_calc_rate(pdev, data->rstrobe, clk_rate, RSTROBE_MAX);
+ timings.rsetup = aemif_calc_rate(pdev, data->rsetup, clk_rate, RSETUP_MAX);
+ timings.whold = aemif_calc_rate(pdev, data->whold, clk_rate, WHOLD_MAX);
+ timings.wstrobe = aemif_calc_rate(pdev, data->wstrobe, clk_rate, WSTROBE_MAX);
+ timings.wsetup = aemif_calc_rate(pdev, data->wsetup, clk_rate, WSETUP_MAX);
- set |= (data->asize & ACR_ASIZE_MASK);
+ set = (data->asize & ACR_ASIZE_MASK);
if (data->enable_ew)
set |= ACR_EW_MASK;
if (data->enable_ss)
@@ -210,7 +255,7 @@ static int aemif_config_abus(struct platform_device *pdev, int csnum)
val |= set;
writel(val, aemif->base + offset);
- return 0;
+ return aemif_set_cs_timings(aemif, data->cs - aemif->cs_offset, &timings);
}
static inline int aemif_cycles_to_nsec(int val, unsigned long clk_rate)
Create an aemif_set_cs_timings() function to isolate the setting of a chip select timing configuration and ease its exportation. Move the check of the configuration validity from aemif_calc_rate() to this new function. Signed-off-by: Bastien Curutchet <bastien.curutchet@bootlin.com> --- drivers/memory/ti-aemif.c | 111 ++++++++++++++++++++++++++------------ 1 file changed, 78 insertions(+), 33 deletions(-)