Fix fdtdec_get_alias_seq() which is not checking full path to certain node and it incorrectly provides incorrect seq number. Checking full path ensure that if alias is present correct seq number is return. This problem was found on ZynqMP zcu102 where are several I2C muxes where the first bus name is i2c@0 and for following muxes incorrect seq numbers are return.
Signed-off-by: Michal Simek michal.simek@xilinx.com ---
I am not sure if there is any macro for max alias length which I can use instead of new macro.
Before: ZynqMP> i2c bus Bus 0: i2c@ff020000 20: gpio@20, offset len 1, flags 0 21: gpio@21, offset len 1, flags 0 75: i2cswitch@75, offset len 1, flags 0 Bus 750: i2c@0 Bus 751: i2c@1 Bus 752: i2c@2 Bus 1: i2c@ff030000 74: i2cswitch@74, offset len 1, flags 0 75: i2cswitch@75, offset len 1, flags 0 Bus 750: i2c@0 Bus 751: i2c@1 Bus 752: i2c@2 Bus 1743: i2c@3 Bus 1744: i2c@4 Bus 750: i2c@0 Bus 751: i2c@1 Bus 752: i2c@2 Bus 1743: i2c@3 Bus 1744: i2c@4 Bus 1755: i2c@5 Bus 1756: i2c@6 Bus 1757: i2c@7
After: ZynqMP> i2c bus Bus 0: i2c@ff020000 20: gpio@20, offset len 1, flags 0 21: gpio@21, offset len 1, flags 0 75: i2cswitch@75, offset len 1, flags 0 Bus 750: i2c@0 Bus 751: i2c@1 Bus 752: i2c@2 Bus 1: i2c@ff030000 74: i2cswitch@74, offset len 1, flags 0 75: i2cswitch@75, offset len 1, flags 0 Bus 1740: i2c@0 Bus 1741: i2c@1 Bus 1742: i2c@2 Bus 1743: i2c@3 Bus 1744: i2c@4 Bus 1750: i2c@0 Bus 1751: i2c@1 Bus 1752: i2c@2 Bus 1753: i2c@3 Bus 1754: i2c@4 Bus 1755: i2c@5 Bus 1756: i2c@6 Bus 1757: i2c@7
Which reflects my aliases i2c0 = &i2c0; i2c750 = &i2c0_75_0; i2c751 = &i2c0_75_1; i2c752 = &i2c0_75_2; i2c1 = &i2c1; i2c1740 = &i2c1_74_0; i2c1741 = &i2c1_74_1; i2c1742 = &i2c1_74_2; i2c1743 = &i2c1_74_3; i2c1744 = &i2c1_74_4; i2c1750 = &i2c1_75_0; i2c1751 = &i2c1_75_1; i2c1752 = &i2c1_75_2; i2c1753 = &i2c1_75_3; i2c1754 = &i2c1_75_4; i2c1755 = &i2c1_75_5; i2c1756 = &i2c1_75_6; i2c1757 = &i2c1_75_7;
--- lib/fdtdec.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/lib/fdtdec.c b/lib/fdtdec.c index 70acc29c924d..79efcf0cd6b0 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -506,6 +506,8 @@ int fdtdec_add_aliases_for_id(const void *blob, const char *name, return num_found; }
+#define FDT_ALIAS_PATH_LEN 64 + int fdtdec_get_alias_seq(const void *blob, const char *base, int offset, int *seqp) { @@ -514,9 +516,13 @@ int fdtdec_get_alias_seq(const void *blob, const char *base, int offset, int find_namelen; int prop_offset; int aliases; + char buf[FDT_ALIAS_PATH_LEN]; + + fdt_get_path(blob, offset, buf, sizeof(buf));
find_name = fdt_get_name(blob, offset, &find_namelen); - debug("Looking for '%s' at %d, name %s\n", base, offset, find_name); + debug("Looking for '%s' at %d, name %s, buf %s\n", + base, offset, find_name, buf);
aliases = fdt_path_offset(blob, "/aliases"); for (prop_offset = fdt_first_property_offset(blob, aliases); @@ -533,6 +539,13 @@ int fdtdec_get_alias_seq(const void *blob, const char *base, int offset, strncmp(name, base, base_len)) continue;
+ if (len >= FDT_ALIAS_PATH_LEN) + printf("Too long path in aliases node\n"); + + /* Check full path first not to point to incorrect alias */ + if (strncmp(prop, buf, min(len, FDT_ALIAS_PATH_LEN))) + continue; + slash = strrchr(prop, '/'); if (strcmp(slash + 1, find_name)) continue;