[PATCH v3 4/5] fpga: dfl: add fpga dfl bus support to MODULE_DEVICE_TABLE()

From: Xu Yilun
Date: Thu Sep 24 2020 - 13:07:41 EST


Device Feature List (DFL) is a linked list of feature headers within the
device MMIO space. It is used by FPGA to enumerate multiple sub features
within it. Each feature can be uniquely identified by DFL type and
feature id, which can be read out from feature headers.

A fpga dfl bus helps DFL framework modularize DFL device drivers for
different sub features. The fpga dfl bus matches its devices and drivers
by DFL type and feature id.

This patch adds fpga dfl bus support to MODULE_DEVICE_TABLE() by adding
info about struct fpga_dfl_device_id in devicetable-offsets.c and add a
fpga dfl entry point in file2alias.c.

Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
Signed-off-by: Wu Hao <hao.wu@xxxxxxxxx>
Signed-off-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
Acked-by: Wu Hao <hao.wu@xxxxxxxxx>
Signed-off-by: Moritz Fischer <mdf@xxxxxxxxxx>
---
v2: add comments for the format of modalias
v3: changes the names from dfl_XXX to fpga_dfl_XXX
delete the comments of valid bits for modalias format
---
scripts/mod/devicetable-offsets.c | 4 ++++
scripts/mod/file2alias.c | 13 +++++++++++++
2 files changed, 17 insertions(+)

diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c
index 27007c1..25fe19b 100644
--- a/scripts/mod/devicetable-offsets.c
+++ b/scripts/mod/devicetable-offsets.c
@@ -243,5 +243,9 @@ int main(void)
DEVID(mhi_device_id);
DEVID_FIELD(mhi_device_id, chan);

+ DEVID(fpga_dfl_device_id);
+ DEVID_FIELD(fpga_dfl_device_id, type);
+ DEVID_FIELD(fpga_dfl_device_id, feature_id);
+
return 0;
}
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 2417dd1..4fffdd5 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1368,6 +1368,18 @@ static int do_mhi_entry(const char *filename, void *symval, char *alias)
return 1;
}

+/* Looks like: fpga-dfl:tNfN */
+static int do_fpga_dfl_entry(const char *filename, void *symval, char *alias)
+{
+ DEF_FIELD(symval, fpga_dfl_device_id, type);
+ DEF_FIELD(symval, fpga_dfl_device_id, feature_id);
+
+ sprintf(alias, "fpga-dfl:t%04Xf%04X", type, feature_id);
+
+ add_wildcard(alias);
+ return 1;
+}
+
/* Does namelen bytes of name exactly match the symbol? */
static bool sym_is(const char *name, unsigned namelen, const char *symbol)
{
@@ -1442,6 +1454,7 @@ static const struct devtable devtable[] = {
{"tee", SIZE_tee_client_device_id, do_tee_entry},
{"wmi", SIZE_wmi_device_id, do_wmi_entry},
{"mhi", SIZE_mhi_device_id, do_mhi_entry},
+ {"fpgadfl", SIZE_fpga_dfl_device_id, do_fpga_dfl_entry},
};

/* Create MODULE_ALIAS() statements.
--
2.7.4