summaryrefslogtreecommitdiff
path: root/arch/arm/cpu/armv7/tegra2/clock.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/cpu/armv7/tegra2/clock.c')
-rw-r--r--arch/arm/cpu/armv7/tegra2/clock.c121
1 files changed, 99 insertions, 22 deletions
diff --git a/arch/arm/cpu/armv7/tegra2/clock.c b/arch/arm/cpu/armv7/tegra2/clock.c
index 11d2346d8..39376ab86 100644
--- a/arch/arm/cpu/armv7/tegra2/clock.c
+++ b/arch/arm/cpu/armv7/tegra2/clock.c
@@ -28,6 +28,7 @@
#include <asm/arch/tegra2.h>
#include <common.h>
#include <div64.h>
+#include <fdtdec.h>
/*
* This is our record of the current clock rate of each clock. We don't
@@ -67,6 +68,7 @@ enum clock_type_id {
CLOCK_TYPE_MCPT,
CLOCK_TYPE_PCM,
CLOCK_TYPE_PCMT,
+ CLOCK_TYPE_PCMT16, /* CLOCK_TYPE_PCMT with 16-bit divider */
CLOCK_TYPE_PCXTS,
CLOCK_TYPE_PDCT,
@@ -98,6 +100,7 @@ static enum clock_id clock_source[CLOCK_TYPE_COUNT][CLOCK_MAX_MUX] = {
{ CLK(MEMORY), CLK(CGENERAL), CLK(PERIPH), CLK(OSC) },
{ CLK(PERIPH), CLK(CGENERAL), CLK(MEMORY), CLK(NONE) },
{ CLK(PERIPH), CLK(CGENERAL), CLK(MEMORY), CLK(OSC) },
+ { CLK(PERIPH), CLK(CGENERAL), CLK(MEMORY), CLK(OSC) },
{ CLK(PERIPH), CLK(CGENERAL), CLK(XCPU), CLK(OSC) },
{ CLK(PERIPH), CLK(DISPLAY), CLK(CGENERAL), CLK(OSC) },
};
@@ -211,8 +214,8 @@ static enum clock_type_id clock_periph_type[PERIPHC_COUNT] = {
/* 0x08 */
TYPE(PERIPHC_XIO, CLOCK_TYPE_PCMT),
- TYPE(PERIPHC_I2C1, CLOCK_TYPE_PCMT),
- TYPE(PERIPHC_DVC_I2C, CLOCK_TYPE_PCMT),
+ TYPE(PERIPHC_I2C1, CLOCK_TYPE_PCMT16),
+ TYPE(PERIPHC_DVC_I2C, CLOCK_TYPE_PCMT16),
TYPE(PERIPHC_TWC, CLOCK_TYPE_PCMT),
TYPE(PERIPHC_NONE, CLOCK_TYPE_NONE),
TYPE(PERIPHC_SPI1, CLOCK_TYPE_PCMT),
@@ -246,7 +249,7 @@ static enum clock_type_id clock_periph_type[PERIPHC_COUNT] = {
TYPE(PERIPHC_HDMI, CLOCK_TYPE_PDCT),
TYPE(PERIPHC_NONE, CLOCK_TYPE_NONE),
TYPE(PERIPHC_TVDAC, CLOCK_TYPE_PDCT),
- TYPE(PERIPHC_I2C2, CLOCK_TYPE_PCMT),
+ TYPE(PERIPHC_I2C2, CLOCK_TYPE_PCMT16),
TYPE(PERIPHC_EMC, CLOCK_TYPE_MCPT),
/* 0x28 */
@@ -256,7 +259,7 @@ static enum clock_type_id clock_periph_type[PERIPHC_COUNT] = {
TYPE(PERIPHC_NONE, CLOCK_TYPE_NONE),
TYPE(PERIPHC_NONE, CLOCK_TYPE_NONE),
TYPE(PERIPHC_SPI4, CLOCK_TYPE_PCMT),
- TYPE(PERIPHC_I2C3, CLOCK_TYPE_PCMT),
+ TYPE(PERIPHC_I2C3, CLOCK_TYPE_PCMT16),
TYPE(PERIPHC_SDMMC3, CLOCK_TYPE_PCMT),
/* 0x30 */
@@ -518,14 +521,16 @@ void clock_ll_set_source(enum periph_id periph_id, unsigned source)
* Given the parent's rate and the required rate for the children, this works
* out the peripheral clock divider to use, in 7.1 binary format.
*
+ * @param divider_bits number of divider bits (8 or 16)
* @param parent_rate clock rate of parent clock in Hz
* @param rate required clock rate for this clock
* @return divider which should be used
*/
-static int clk_div7_1_get_divider(unsigned long parent_rate,
- unsigned long rate)
+static int clk_get_divider(unsigned divider_bits, unsigned long parent_rate,
+ unsigned long rate)
{
u64 divider = parent_rate * 2;
+ unsigned max_divider = 1 << divider_bits;
divider += rate - 1;
do_div(divider, rate);
@@ -533,7 +538,7 @@ static int clk_div7_1_get_divider(unsigned long parent_rate,
if ((s64)divider - 2 < 0)
return 0;
- if ((s64)divider - 2 > 255)
+ if ((s64)divider - 2 >= max_divider)
return -1;
return divider - 2;
@@ -571,6 +576,7 @@ unsigned long clock_get_periph_rate(enum periph_id periph_id,
* required child clock rate. This function assumes that a second-stage
* divisor is available which can divide by powers of 2 from 1 to 256.
*
+ * @param divider_bits number of divider bits (8 or 16)
* @param parent_rate clock rate of parent clock in Hz
* @param rate required clock rate for this clock
* @param extra_div value for the second-stage divisor (not set if this
@@ -578,8 +584,8 @@ unsigned long clock_get_periph_rate(enum periph_id periph_id,
* @return divider which should be used, or -1 if nothing is valid
*
*/
-static int find_best_divider(unsigned long parent_rate, unsigned long rate,
- int *extra_div)
+static int find_best_divider(unsigned divider_bits, unsigned long parent_rate,
+ unsigned long rate, int *extra_div)
{
int shift;
int best_divider = -1;
@@ -588,7 +594,8 @@ static int find_best_divider(unsigned long parent_rate, unsigned long rate,
/* try dividers from 1 to 256 and find closest match */
for (shift = 0; shift <= 8 && best_error > 0; shift++) {
unsigned divided_parent = parent_rate >> shift;
- int divider = clk_div7_1_get_divider(divided_parent, rate);
+ int divider = clk_get_divider(divider_bits, divided_parent,
+ rate);
unsigned effective_rate = get_rate_from_divider(divided_parent,
divider);
int error = rate - effective_rate;
@@ -614,10 +621,11 @@ static int find_best_divider(unsigned long parent_rate, unsigned long rate,
* @param periph_id peripheral to start
* @param source PLL id of required parent clock
* @param mux_bits Set to number of bits in mux register: 2 or 4
+ * @param divider_bits Set to number of divider bits (8 or 16)
* @return mux value (0-4, or -1 if not found)
*/
static int get_periph_clock_source(enum periph_id periph_id,
- enum clock_id parent, int *mux_bits)
+ enum clock_id parent, int *mux_bits, int *divider_bits)
{
enum clock_type_id type;
enum periphc_internal_id internal_id;
@@ -631,11 +639,18 @@ static int get_periph_clock_source(enum periph_id periph_id,
type = clock_periph_type[internal_id];
assert(clock_type_id_isvalid(type));
- /* Special case here for the clock with a 4-bit source mux */
+ /*
+ * Special cases here for the clock with a 4-bit source mux and I2C
+ * with its 16-bit divisor
+ */
if (type == CLOCK_TYPE_PCXTS)
*mux_bits = 4;
else
*mux_bits = 2;
+ if (type == CLOCK_TYPE_PCMT16)
+ *divider_bits = 16;
+ else
+ *divider_bits = 8;
for (mux = 0; mux < CLOCK_MAX_MUX; mux++)
if (clock_source[type][mux] == parent)
@@ -661,24 +676,22 @@ static int get_periph_clock_source(enum periph_id periph_id,
* Adjust peripheral PLL to use the given divider and source.
*
* @param periph_id peripheral to adjust
- * @param parent Required parent clock (for source mux)
- * @param divider Required divider in 7.1 format
+ * @param source Source number (0-3 or 0-7)
+ * @param mux_bits Number of mux bits (2 or 4)
+ * @param divider Required divider in 7.1 or 15.1 format
* @return 0 if ok, -1 on error (requesting a parent clock which is not valid
* for this peripheral)
*/
-static int adjust_periph_pll(enum periph_id periph_id,
- enum clock_id parent, unsigned divider)
+static int adjust_periph_pll(enum periph_id periph_id, int source,
+ int mux_bits, unsigned divider)
{
u32 *reg = get_periph_source_reg(periph_id);
- unsigned source;
- int mux_bits;
clrsetbits_le32(reg, OUT_CLK_DIVISOR_MASK,
divider << OUT_CLK_DIVISOR_SHIFT);
udelay(1);
/* work out the source clock and set it */
- source = get_periph_clock_source(periph_id, parent, &mux_bits);
if (source < 0)
return -1;
if (mux_bits == 4) {
@@ -696,14 +709,21 @@ unsigned clock_adjust_periph_pll_div(enum periph_id periph_id,
enum clock_id parent, unsigned rate, int *extra_div)
{
unsigned effective_rate;
+ int mux_bits, divider_bits, source;
int divider;
+ /* work out the source clock and set it */
+ source = get_periph_clock_source(periph_id, parent, &mux_bits,
+ &divider_bits);
+
if (extra_div)
- divider = find_best_divider(pll_rate[parent], rate, extra_div);
+ divider = find_best_divider(divider_bits, pll_rate[parent],
+ rate, extra_div);
else
- divider = clk_div7_1_get_divider(pll_rate[parent], rate);
+ divider = clk_get_divider(divider_bits, pll_rate[parent],
+ rate);
assert(divider >= 0);
- if (adjust_periph_pll(periph_id, parent, divider))
+ if (adjust_periph_pll(periph_id, source, mux_bits, divider))
return -1U;
debug("periph %d, rate=%d, reg=%p = %x\n", periph_id, rate,
get_periph_source_reg(periph_id),
@@ -918,6 +938,63 @@ void clock_ll_start_uart(enum periph_id periph_id)
reset_set_enable(periph_id, 0);
}
+#ifdef CONFIG_OF_CONTROL
+/*
+ * Convert a device tree clock ID to our peripheral ID. They are mostly
+ * the same but we are very cautious so we check that a valid clock ID is
+ * provided.
+ *
+ * @param clk_id Clock ID according to tegra2 device tree binding
+ * @return peripheral ID, or PERIPH_ID_NONE if the clock ID is invalid
+ */
+static enum periph_id clk_id_to_periph_id(int clk_id)
+{
+ if (clk_id > 95)
+ return PERIPH_ID_NONE;
+
+ switch (clk_id) {
+ case 1:
+ case 2:
+ case 7:
+ case 10:
+ case 20:
+ case 30:
+ case 35:
+ case 49:
+ case 56:
+ case 74:
+ case 76:
+ case 77:
+ case 78:
+ case 79:
+ case 80:
+ case 81:
+ case 82:
+ case 83:
+ case 91:
+ case 95:
+ return PERIPH_ID_NONE;
+ default:
+ return clk_id;
+ }
+}
+
+int clock_decode_periph_id(const void *blob, int node)
+{
+ enum periph_id id;
+ u32 cell[2];
+ int err;
+
+ err = fdtdec_get_int_array(blob, node, "clocks", cell,
+ ARRAY_SIZE(cell));
+ if (err)
+ return -1;
+ id = clk_id_to_periph_id(cell[1]);
+ assert(clock_periph_id_isvalid(id));
+ return id;
+}
+#endif /* CONFIG_OF_CONTROL */
+
int clock_verify(void)
{
struct clk_pll *pll = get_pll(CLOCK_ID_PERIPH);
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-10-31 18:16:36 +0000