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| author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2017-04-24 14:45:40 +1000 |
|---|---|---|
| committer | Stewart Smith <stewart@linux.vnet.ibm.com> | 2017-04-28 15:11:15 +1000 |
| commit | 0ccb51dcda80a9c7fded7ca45cd0ba97f81401c7 (patch) | |
| tree | 70890872f3e493514b0512a9ca9dc212bef74140 /hdata/i2c.c | |
| parent | 06117d0c466461458039d54e9cabcd706e4d8516 (diff) | |
| download | skiboot-0ccb51dcda80a9c7fded7ca45cd0ba97f81401c7.zip skiboot-0ccb51dcda80a9c7fded7ca45cd0ba97f81401c7.tar.gz skiboot-0ccb51dcda80a9c7fded7ca45cd0ba97f81401c7.tar.bz2 | |
hdata/i2c: Fix bus and clock frequencies
The clock-frequency of the i2c master should be derived from
the xscom bus frequency (itself derived from the nest frequency).
The bus-frequency of the i2c bus should be in Hz so convert the
HDAT value from kHz to Hz.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Diffstat (limited to 'hdata/i2c.c')
| -rw-r--r-- | hdata/i2c.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/hdata/i2c.c b/hdata/i2c.c index 5a74a7f..24e9257 100644 --- a/hdata/i2c.c +++ b/hdata/i2c.c @@ -31,6 +31,7 @@ static struct dt_node *get_i2cm_node(struct dt_node *xscom, int engine) { uint64_t xscom_base = P9_I2CM_XSCOM_BASE + P9_I2CM_XSCOM_SIZE * engine; struct dt_node *i2cm; + uint64_t freq, clock; i2cm = dt_find_by_name_addr(xscom, "i2cm", xscom_base); if (!i2cm) { @@ -45,8 +46,12 @@ static struct dt_node *get_i2cm_node(struct dt_node *xscom, int engine) dt_add_property_cells(i2cm, "#address-cells", 1); dt_add_property_cells(i2cm, "chip-engine#", engine); - /* XXX: verify this */ - dt_add_property_cells(i2cm, "clock-frequency", 150000000); + freq = dt_prop_get_u64_def(xscom, "bus-frequency", 0); + clock = (u32)(freq / 4); + if (clock) + dt_add_property_cells(i2cm, "clock-frequency", clock); + else + dt_add_property_cells(i2cm, "clock-frequency", 150000000); } return i2cm; @@ -73,7 +78,7 @@ static struct dt_node *get_bus_node(struct dt_node *i2cm, int port, int freq) * reduce the frequency to something that all devices * can tolerate. */ - dt_add_property_cells(bus, "bus-frequency", freq); + dt_add_property_cells(bus, "bus-frequency", freq * 1000); } return bus; |