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| author | Laurentiu Tudor <laurentiu.tudor@nxp.com> | 2017-07-19 14:42:30 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-07-30 08:23:27 -0700 |
| commit | b064d0e6e42ed4774c42bfbec0db60f8249a9de2 (patch) | |
| tree | 28a51e979f69635aa32d128abf95b074e5430bb4 | |
| parent | f1027a8cb8d77ed00719d110c03a6aaf73fd137a (diff) | |
| download | linux-b064d0e6e42ed4774c42bfbec0db60f8249a9de2.tar.gz linux-b064d0e6e42ed4774c42bfbec0db60f8249a9de2.tar.bz2 linux-b064d0e6e42ed4774c42bfbec0db60f8249a9de2.zip | |
staging: fsl-mc: don't use raw device io functions
As raw device io functions are not portable and don't handle byte-order
(triggering suspicion that endianness isn't handled well) switch to
using the standard api.
Since MC expects LE byte-order and the upper layers already take care
of that, we need to trick the device io api by doing a LE -> CPU
conversion just before calling it. This way, the CPU -> LE conversion
done in the api puts the data back in the right byte-order. Obviously,
for reads the extra step is mirrored: there's a CPU -> LE conversion
following the API call.
Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/fsl-mc/bus/mc-sys.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/drivers/staging/fsl-mc/bus/mc-sys.c b/drivers/staging/fsl-mc/bus/mc-sys.c index 195d9f347788..8a6dc477920f 100644 --- a/drivers/staging/fsl-mc/bus/mc-sys.c +++ b/drivers/staging/fsl-mc/bus/mc-sys.c @@ -126,12 +126,15 @@ static inline void mc_write_command(struct mc_command __iomem *portal, /* copy command parameters into the portal */ for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++) - __raw_writeq(cmd->params[i], &portal->params[i]); - /* ensure command params are committed before submitting it */ - wmb(); + /* + * Data is already in the expected LE byte-order. Do an + * extra LE -> CPU conversion so that the CPU -> LE done in + * the device io write api puts it back in the right order. + */ + writeq_relaxed(le64_to_cpu(cmd->params[i]), &portal->params[i]); /* submit the command by writing the header */ - __raw_writeq(cmd->header, &portal->header); + writeq(le64_to_cpu(cmd->header), &portal->header); } /** @@ -151,14 +154,20 @@ static inline enum mc_cmd_status mc_read_response(struct mc_command __iomem * enum mc_cmd_status status; /* Copy command response header from MC portal: */ - resp->header = __raw_readq(&portal->header); + resp->header = cpu_to_le64(readq_relaxed(&portal->header)); status = mc_cmd_hdr_read_status(resp); if (status != MC_CMD_STATUS_OK) return status; /* Copy command response data from MC portal: */ for (i = 0; i < MC_CMD_NUM_OF_PARAMS; i++) - resp->params[i] = __raw_readq(&portal->params[i]); + /* + * Data is expected to be in LE byte-order. Do an + * extra CPU -> LE to revert the LE -> CPU done in + * the device io read api. + */ + resp->params[i] = + cpu_to_le64(readq_relaxed(&portal->params[i])); return status; } |