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Diffstat (limited to 'arch/arm/mach-tegra/clock.c')
-rw-r--r--arch/arm/mach-tegra/clock.c90
1 files changed, 88 insertions, 2 deletions
diff --git a/arch/arm/mach-tegra/clock.c b/arch/arm/mach-tegra/clock.c
index 36eabc8..3bb7233 100644
--- a/arch/arm/mach-tegra/clock.c
+++ b/arch/arm/mach-tegra/clock.c
@@ -206,6 +206,29 @@ int clock_ll_set_source_bits(enum periph_id periph_id, int mux_bits,
return 0;
}
+static int clock_ll_get_source_bits(enum periph_id periph_id, int mux_bits)
+{
+ u32 *reg = get_periph_source_reg(periph_id);
+ u32 val = readl(reg);
+
+ switch (mux_bits) {
+ case MASK_BITS_31_30:
+ val >>= OUT_CLK_SOURCE_31_30_SHIFT;
+ val &= OUT_CLK_SOURCE_31_30_MASK;
+ return val;
+ case MASK_BITS_31_29:
+ val >>= OUT_CLK_SOURCE_31_29_SHIFT;
+ val &= OUT_CLK_SOURCE_31_29_MASK;
+ return val;
+ case MASK_BITS_31_28:
+ val >>= OUT_CLK_SOURCE_31_28_SHIFT;
+ val &= OUT_CLK_SOURCE_31_28_MASK;
+ return val;
+ default:
+ return -1;
+ }
+}
+
void clock_ll_set_source(enum periph_id periph_id, unsigned source)
{
clock_ll_set_source_bits(periph_id, MASK_BITS_31_30, source);
@@ -288,9 +311,43 @@ unsigned long clock_get_periph_rate(enum periph_id periph_id,
enum clock_id parent)
{
u32 *reg = get_periph_source_reg(periph_id);
+ unsigned parent_rate = pll_rate[parent];
+ int div = (readl(reg) & OUT_CLK_DIVISOR_MASK) >> OUT_CLK_DIVISOR_SHIFT;
+
+ switch (periph_id) {
+ case PERIPH_ID_UART1:
+ case PERIPH_ID_UART2:
+ case PERIPH_ID_UART3:
+ case PERIPH_ID_UART4:
+ case PERIPH_ID_UART5:
+#ifdef CONFIG_TEGRA20
+ /* There's no divider for these clocks in this SoC. */
+ return parent_rate;
+#else
+ /*
+ * This undoes the +2 in get_rate_from_divider() which I
+ * believe is incorrect. Ideally we would fix
+ * get_rate_from_divider(), but... Removing the +2 from
+ * get_rate_from_divider() would probably require remove the -2
+ * from the tail of clk_get_divider() since I believe that's
+ * only there to invert get_rate_from_divider()'s +2. Observe
+ * how find_best_divider() uses those two functions together.
+ * However, doing so breaks other stuff, such as Seaboard's
+ * display, likely due to clock_set_pllout()'s call to
+ * clk_get_divider(). Attempting to fix that by making
+ * clock_set_pllout() subtract 2 from clk_get_divider()'s
+ * return value doesn't help. In summary this clock driver is
+ * quite broken but I'm afraid I have no idea how to fix it
+ * without completely replacing it.
+ */
+ div -= 2;
+ break;
+#endif
+ default:
+ break;
+ }
- return get_rate_from_divider(pll_rate[parent],
- (readl(reg) & OUT_CLK_DIVISOR_MASK) >> OUT_CLK_DIVISOR_SHIFT);
+ return get_rate_from_divider(parent_rate, div);
}
/**
@@ -363,6 +420,20 @@ static int adjust_periph_pll(enum periph_id periph_id, int source,
return 0;
}
+enum clock_id clock_get_periph_parent(enum periph_id periph_id)
+{
+ int err, mux_bits, divider_bits, type;
+ int source;
+
+ err = get_periph_clock_info(periph_id, &mux_bits, &divider_bits, &type);
+ if (err)
+ return CLOCK_ID_NONE;
+
+ source = clock_ll_get_source_bits(periph_id, mux_bits);
+
+ return get_periph_clock_id(periph_id, source);
+}
+
unsigned clock_adjust_periph_pll_div(enum periph_id periph_id,
enum clock_id parent, unsigned rate, int *extra_div)
{
@@ -612,6 +683,8 @@ int clock_verify(void)
void clock_init(void)
{
+ int i;
+
pll_rate[CLOCK_ID_CGENERAL] = clock_get_rate(CLOCK_ID_CGENERAL);
pll_rate[CLOCK_ID_MEMORY] = clock_get_rate(CLOCK_ID_MEMORY);
pll_rate[CLOCK_ID_PERIPH] = clock_get_rate(CLOCK_ID_PERIPH);
@@ -630,6 +703,19 @@ void clock_init(void)
debug("PLLU = %d\n", pll_rate[CLOCK_ID_USB]);
debug("PLLD = %d\n", pll_rate[CLOCK_ID_DISPLAY]);
debug("PLLX = %d\n", pll_rate[CLOCK_ID_XCPU]);
+
+ for (i = 0; periph_clk_init_table[i].periph_id != -1; i++) {
+ enum periph_id periph_id;
+ enum clock_id parent;
+ int source, mux_bits, divider_bits;
+
+ periph_id = periph_clk_init_table[i].periph_id;
+ parent = periph_clk_init_table[i].parent_clock_id;
+
+ source = get_periph_clock_source(periph_id, parent, &mux_bits,
+ &divider_bits);
+ clock_ll_set_source_bits(periph_id, mux_bits, source);
+ }
}
static void set_avp_clock_source(u32 src)