dtoc: Scan drivers for available information

At present we simply record the name of a driver parsed from its
implementation file. We also need to get the uclass and a few other
things so we can instantiate devices at build time. Add support for
collecting this information. This requires parsing each driver file.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 184 insertions, 10 deletions

diff --git a/tools/dtoc/src_scan.py b/tools/dtoc/src_scan.py
index f63c9fc166e..095fb6d4766 100644
--- a/tools/dtoc/src_scan.py
+++ b/tools/dtoc/src_scan.py
@@ -54,15 +54,30 @@ class Driver:
 
     Attributes:
         name: Name of driver. For U_BOOT_DRIVER(x) this is 'x'
+        fname: Filename where the driver was found
+        uclass_id: Name of uclass, e.g. 'UCLASS_I2C'
+        compat: Driver data for each compatible string:
+            key: Compatible string, e.g. 'rockchip,rk3288-grf'
+            value: Driver data, e,g, 'ROCKCHIP_SYSCON_GRF', or None
+        fname: Filename where the driver was found
+        priv (str): struct name of the priv_auto member, e.g. 'serial_priv'
     """
-    def __init__(self, name):
+    def __init__(self, name, fname):
         self.name = name
+        self.fname = fname
+        self.uclass_id = None
+        self.compat = None
+        self.priv = ''
 
     def __eq__(self, other):
-        return self.name == other.name
+        return (self.name == other.name and
+                self.uclass_id == other.uclass_id and
+                self.compat == other.compat and
+                self.priv == other.priv)
 
     def __repr__(self):
-        return "Driver(name='%s')" % self.name
+        return ("Driver(name='%s', uclass_id='%s', compat=%s, priv=%s)" %
+                (self.name, self.uclass_id, self.compat, self.priv))
 
 
 class Scanner:
@@ -81,6 +96,12 @@ class Scanner:
         _warning_disabled: true to disable warnings about driver names not found
         _drivers_additional (list or str): List of additional drivers to use
             during scanning
+        _of_match: Dict holding information about compatible strings
+            key: Name of struct udevice_id variable
+            value: Dict of compatible info in that variable:
+               key: Compatible string, e.g. 'rockchip,rk3288-grf'
+               value: Driver data, e,g, 'ROCKCHIP_SYSCON_GRF', or None
+        _compat_to_driver: Maps compatible strings to Driver
     """
     def __init__(self, basedir, warning_disabled, drivers_additional):
         """Set up a new Scanner
@@ -94,6 +115,8 @@ class Scanner:
         self._driver_aliases = {}
         self._drivers_additional = drivers_additional or []
         self._warning_disabled = warning_disabled
+        self._of_match = {}
+        self._compat_to_driver = {}
 
     def get_normalized_compat_name(self, node):
         """Get a node's normalized compat name
@@ -131,10 +154,163 @@ class Scanner:
 
         return compat_list_c[0], compat_list_c[1:]
 
+    @classmethod
+    def _get_re_for_member(cls, member):
+        """_get_re_for_member: Get a compiled regular expression
+
+        Args:
+            member (str): Struct member name, e.g. 'priv_auto'
+
+        Returns:
+            re.Pattern: Compiled regular expression that parses:
+
+               .member = sizeof(struct fred),
+
+            and returns "fred" as group 1
+        """
+        return re.compile(r'^\s*.%s\s*=\s*sizeof\(struct\s+(.*)\),$' % member)
+
+    def _parse_driver(self, fname, buff):
+        """Parse a C file to extract driver information contained within
+
+        This parses U_BOOT_DRIVER() structs to obtain various pieces of useful
+        information.
+
+        It updates the following members:
+            _drivers - updated with new Driver records for each driver found
+                in the file
+            _of_match - updated with each compatible string found in the file
+            _compat_to_driver - Maps compatible string to Driver
+
+        Args:
+            fname (str): Filename being parsed (used for warnings)
+            buff (str): Contents of file
+
+        Raises:
+            ValueError: Compatible variable is mentioned in .of_match in
+                U_BOOT_DRIVER() but not found in the file
+        """
+        # Dict holding information about compatible strings collected in this
+        # function so far
+        #    key: Name of struct udevice_id variable
+        #    value: Dict of compatible info in that variable:
+        #       key: Compatible string, e.g. 'rockchip,rk3288-grf'
+        #       value: Driver data, e,g, 'ROCKCHIP_SYSCON_GRF', or None
+        of_match = {}
+
+        # Dict holding driver information collected in this function so far
+        #    key: Driver name (C name as in U_BOOT_DRIVER(xxx))
+        #    value: Driver
+        drivers = {}
+
+        # Collect the driver info
+        driver = None
+        re_driver = re.compile(r'U_BOOT_DRIVER\((.*)\)')
+
+        # Collect the uclass ID, e.g. 'UCLASS_SPI'
+        re_id = re.compile(r'\s*\.id\s*=\s*(UCLASS_[A-Z0-9_]+)')
+
+        # Collect the compatible string, e.g. 'rockchip,rk3288-grf'
+        compat = None
+        re_compat = re.compile(r'{\s*.compatible\s*=\s*"(.*)"\s*'
+                               r'(,\s*.data\s*=\s*(\S*))?\s*},')
+
+        # This is a dict of compatible strings that were found:
+        #    key: Compatible string, e.g. 'rockchip,rk3288-grf'
+        #    value: Driver data, e,g, 'ROCKCHIP_SYSCON_GRF', or None
+        compat_dict = {}
+
+        # Holds the var nane of the udevice_id list, e.g.
+        # 'rk3288_syscon_ids_noc' in
+        # static const struct udevice_id rk3288_syscon_ids_noc[] = {
+        ids_name = None
+        re_ids = re.compile(r'struct udevice_id (.*)\[\]\s*=')
+
+        # Matches the references to the udevice_id list
+        re_of_match = re.compile(
+            r'\.of_match\s*=\s*(of_match_ptr\()?([a-z0-9_]+)(\))?,')
+
+        # Matches the struct name for priv
+        re_priv = self._get_re_for_member('priv_auto')
+
+        prefix = ''
+        for line in buff.splitlines():
+            # Handle line continuation
+            if prefix:
+                line = prefix + line
+                prefix = ''
+            if line.endswith('\\'):
+                prefix = line[:-1]
+                continue
+
+            driver_match = re_driver.search(line)
+
+            # If this line contains U_BOOT_DRIVER()...
+            if driver:
+                m_id = re_id.search(line)
+                m_of_match = re_of_match.search(line)
+                m_priv = re_priv.match(line)
+                if m_priv:
+                    driver.priv = m_priv.group(1)
+                elif m_id:
+                    driver.uclass_id = m_id.group(1)
+                elif m_of_match:
+                    compat = m_of_match.group(2)
+                elif '};' in line:
+                    if driver.uclass_id and compat:
+                        if compat not in of_match:
+                            raise ValueError(
+                                "%s: Unknown compatible var '%s' (found: %s)" %
+                                (fname, compat, ','.join(of_match.keys())))
+                        driver.compat = of_match[compat]
+
+                        # This needs to be deterministic, since a driver may
+                        # have multiple compatible strings pointing to it.
+                        # We record the one earliest in the alphabet so it
+                        # will produce the same result on all machines.
+                        for compat_id in of_match[compat]:
+                            old = self._compat_to_driver.get(compat_id)
+                            if not old or driver.name < old.name:
+                                self._compat_to_driver[compat_id] = driver
+                        drivers[driver.name] = driver
+                    else:
+                        # The driver does not have a uclass or compat string.
+                        # The first is required but the second is not, so just
+                        # ignore this.
+                        pass
+                    driver = None
+                    ids_name = None
+                    compat = None
+                    compat_dict = {}
+
+            elif ids_name:
+                compat_m = re_compat.search(line)
+                if compat_m:
+                    compat_dict[compat_m.group(1)] = compat_m.group(3)
+                elif '};' in line:
+                    of_match[ids_name] = compat_dict
+                    ids_name = None
+            elif driver_match:
+                driver_name = driver_match.group(1)
+                driver = Driver(driver_name, fname)
+            else:
+                ids_m = re_ids.search(line)
+                if ids_m:
+                    ids_name = ids_m.group(1)
+
+        # Make the updates based on what we found
+        self._drivers.update(drivers)
+        self._of_match.update(of_match)
+
     def scan_driver(self, fname):
         """Scan a driver file to build a list of driver names and aliases
 
-        This procedure will populate self._drivers and self._driver_aliases
+        It updates the following members:
+            _drivers - updated with new Driver records for each driver found
+                in the file
+            _of_match - updated with each compatible string found in the file
+            _compat_to_driver - Maps compatible string to Driver
+            _driver_aliases - Maps alias names to driver name
 
         Args
             fname: Driver filename to scan
@@ -147,12 +323,10 @@ class Scanner:
                 print("Skipping file '%s' due to unicode error" % fname)
                 return
 
-            # The following re will search for driver names declared as
-            # U_BOOT_DRIVER(driver_name)
-            drivers = re.findall(r'U_BOOT_DRIVER\((.*)\)', buff)
-
-            for driver in drivers:
-                self._drivers[driver] = Driver(driver)
+            # If this file has any U_BOOT_DRIVER() declarations, process it to
+            # obtain driver information
+            if 'U_BOOT_DRIVER' in buff:
+                self._parse_driver(fname, buff)
 
             # The following re will search for driver aliases declared as
             # DM_DRIVER_ALIAS(alias, driver_name)