From: Mauro Carvalho Chehab <mchehab@redhat.com>
Date: Tue, 28 Sep 2010 14:34:15 -0400
Subject: [edac] i7300_edac: improve inline comments/documentation
Message-id: <20100928113415.06ac5120@pedra>
Patchwork-id: 28452
O-Subject: [PATCH RHEL5 21/27] i7300_edac: Improve comments
Bugzilla: 487428
RH-Acked-by: Prarit Bhargava <prarit@redhat.com>
This is basically a cleanup patch, improving the comments for each
function.
While here, do a few cleanups.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
diff --git a/drivers/edac/i7300_edac.c b/drivers/edac/i7300_edac.c
index 6278209..a2a9ad4 100644
--- a/drivers/edac/i7300_edac.c
+++ b/drivers/edac/i7300_edac.c
@@ -122,14 +122,6 @@ static struct edac_pci_ctl_info *i7300_pci;
***************************************************/
/*
- * I7300 devices:
- * All 3 functions of Device 16 (0,1,2) share the SAME DID and
- * uses PCI_DEVICE_ID_INTEL_I7300_MCH_ERR for device 16 (0,1,2).
- * PCI_DEVICE_ID_INTEL_I7300_MCH_FB0 is used for device 21 (0,1)
- * and PCI_DEVICE_ID_INTEL_I7300_MCH_FB1 is used for device 21 (0,1).
- */
-
-/*
* Device 16,
* Function 0: System Address (not documented)
* Function 1: Memory Branch Map, Control, Errors Register
@@ -345,9 +337,24 @@ static const char *ferr_global_lo_name[] = {
* i7300 Functions related to error detection
********************************************/
-const char *get_err_from_table(const char *table[], int size, int pos)
+/**
+ * get_err_from_table() - Gets the error message from a table
+ * @table: table name (array of char *)
+ * @size: number of elements at the table
+ * @pos: position of the element to be returned
+ *
+ * This is a small routine that gets the pos-th element of a table. If the
+ * element doesn't exist (or it is empty), it returns "reserved".
+ * Instead of calling it directly, the better is to call via the macro
+ * GET_ERR_FROM_TABLE(), that automatically checks the table size via
+ * ARRAY_SIZE() macro
+ */
+static const char *get_err_from_table(const char *table[], int size, int pos)
{
- if (pos >= size)
+ if (unlikely(pos >= size))
+ return "Reserved";
+
+ if (unlikely(!table[pos]))
return "Reserved";
return table[pos];
@@ -356,10 +363,11 @@ const char *get_err_from_table(const char *table[], int size, int pos)
#define GET_ERR_FROM_TABLE(table, pos) \
get_err_from_table(table, ARRAY_SIZE(table), pos)
-/*
- * i7300_process_error_global Retrieve the hardware error information from
- * the hardware and cache it in the 'info'
- * structure
+/**
+ * i7300_process_error_global() - Retrieve the hardware error information from
+ * the hardware global error registers and
+ * sends it to dmesg
+ * @mci: struct mem_ctl_info pointer
*/
static void i7300_process_error_global(struct mem_ctl_info *mci)
{
@@ -410,10 +418,11 @@ error_global:
is_fatal ? "Fatal" : "NOT fatal", specific);
}
-/*
- * i7300_process_fbd_error Retrieve the hardware error information from
- * the hardware and cache it in the 'info'
- * structure
+/**
+ * i7300_process_fbd_error() - Retrieve the hardware error information from
+ * the FBD error registers and sends it via
+ * EDAC error API calls
+ * @mci: struct mem_ctl_info pointer
*/
static void i7300_process_fbd_error(struct mem_ctl_info *mci)
{
@@ -524,10 +533,9 @@ static void i7300_process_fbd_error(struct mem_ctl_info *mci)
return;
}
-/*
- * i7300_check_error Retrieve the hardware error information from
- * the hardware and cache it in the 'info'
- * structure
+/**
+ * i7300_check_error() - Calls the error checking subroutines
+ * @mci: struct mem_ctl_info pointer
*/
static void i7300_check_error(struct mem_ctl_info *mci)
{
@@ -535,11 +543,9 @@ static void i7300_check_error(struct mem_ctl_info *mci)
i7300_process_fbd_error(mci);
};
-/*
- * i7300_clear_error Retrieve any error from the hardware
- * but do NOT process that error.
- * Used for 'clearing' out of previous errors
- * Called by the Core module.
+/**
+ * i7300_clear_error() - Clears the error registers
+ * @mci: struct mem_ctl_info pointer
*/
static void i7300_clear_error(struct mem_ctl_info *mci)
{
@@ -573,9 +579,10 @@ static void i7300_clear_error(struct mem_ctl_info *mci)
FERR_NF_FBD, value);
}
-/*
- * i7300_enable_error_reporting
- * Turn on the memory reporting features of the hardware
+/**
+ * i7300_enable_error_reporting() - Enable the memory reporting logic at the
+ * hardware
+ * @mci: struct mem_ctl_info pointer
*/
static void i7300_enable_error_reporting(struct mem_ctl_info *mci)
{
@@ -597,10 +604,14 @@ static void i7300_enable_error_reporting(struct mem_ctl_info *mci)
* i7300 Functions related to memory enumberation
************************************************/
-/*
- * determine_mtr(pvt, csrow, channel)
- *
- * return the proper MTR register as determine by the csrow and desired channel
+/**
+ * decode_mtr() - Decodes the MTR descriptor, filling the edac structs
+ * @pvt: pointer to the private data struct used by i7300 driver
+ * @slot: DIMM slot (0 to 7)
+ * @ch: Channel number within the branch (0 or 1)
+ * @branch: Branch number (0 or 1)
+ * @dinfo: Pointer to DIMM info where dimm size is stored
+ * @p_csrow: Pointer to the struct csrow_info that corresponds to that element
*/
static int decode_mtr(struct i7300_pvt *pvt,
int slot, int ch, int branch,
@@ -619,14 +630,8 @@ static int decode_mtr(struct i7300_pvt *pvt,
ans ? "Present" : "NOT Present");
/* Determine if there is a DIMM present in this DIMM slot */
-
-#if 0
- if (!amb_present || !ans)
- return 0;
-#else
if (!ans)
return 0;
-#endif
/* Start with the number of bits for a Bank
* on the DRAM */
@@ -692,14 +697,15 @@ static int decode_mtr(struct i7300_pvt *pvt,
return mtr;
}
-/*
- * print_dimm_size
+/**
+ * print_dimm_size() - Prints dump of the memory organization
+ * @pvt: pointer to the private data struct used by i7300 driver
*
- * also will output a DIMM matrix map, if debug is enabled, for viewing
- * how the DIMMs are populated
+ * Useful for debug. If debug is disabled, this routine do nothing
*/
static void print_dimm_size(struct i7300_pvt *pvt)
{
+#ifdef CONFIG_EDAC_DEBUG
struct i7300_dimm_info *dinfo;
char *p;
int space, n;
@@ -751,30 +757,26 @@ static void print_dimm_size(struct i7300_pvt *pvt)
debugf2("%s\n", pvt->tmp_prt_buffer);
p = pvt->tmp_prt_buffer;
space = PAGE_SIZE;
+#endif
}
-/*
- * i7300_init_csrows Initialize the 'csrows' table within
- * the mci control structure with the
- * addressing of memory.
- *
- * return:
- * 0 success
- * 1 no actual memory found on this MC
+/**
+ * i7300_init_csrows() - Initialize the 'csrows' table within
+ * the mci control structure with the
+ * addressing of memory.
+ * @mci: struct mem_ctl_info pointer
*/
static int i7300_init_csrows(struct mem_ctl_info *mci)
{
struct i7300_pvt *pvt;
struct i7300_dimm_info *dinfo;
struct csrow_info *p_csrow;
- int empty;
+ int rc = -ENODEV;
int mtr;
int ch, branch, slot, channel;
pvt = mci->pvt_info;
- empty = 1; /* Assume NO memory */
-
debugf2("Memory Technology Registers:\n");
/* Get the AMB present registers for the four channels */
@@ -819,14 +821,19 @@ static int i7300_init_csrows(struct mem_ctl_info *mci)
p_csrow->last_page = 9 + slot * 20;
p_csrow->page_mask = 0xfff;
- empty = 0;
+ rc = 0;
}
}
}
- return empty;
+ return rc;
}
+/**
+ * decode_mir() - Decodes Memory Interleave Register (MIR) info
+ * @int mir_no: number of the MIR register to decode
+ * @mir: array with the MIR data cached on the driver
+ */
static void decode_mir(int mir_no, u16 mir[MAX_MIR])
{
if (mir[mir_no] & 3)
@@ -837,11 +844,11 @@ static void decode_mir(int mir_no, u16 mir[MAX_MIR])
(mir[mir_no] & 2) ? "B1": "");
}
-/*
- * i7300_get_mc_regs read in the necessary registers and
- * cache locally
+/**
+ * i7300_get_mc_regs() - Get the contents of the MC enumeration registers
+ * @mci: struct mem_ctl_info pointer
*
- * Fills in the private data members
+ * Data read is cached internally for its usage when needed
*/
static int i7300_get_mc_regs(struct mem_ctl_info *mci)
{
@@ -907,9 +914,9 @@ static int i7300_get_mc_regs(struct mem_ctl_info *mci)
* i7300 Functions related to device probe/release
*************************************************/
-/*
- * i7300_put_devices 'put' all the devices that we have
- * reserved via 'get'
+/**
+ * i7300_put_devices() - Release the PCI devices
+ * @mci: struct mem_ctl_info pointer
*/
static void i7300_put_devices(struct mem_ctl_info *mci)
{
@@ -925,13 +932,18 @@ static void i7300_put_devices(struct mem_ctl_info *mci)
pci_dev_put(pvt->pci_dev_16_1_fsb_addr_map);
}
-/*
- * i7300_get_devices Find and perform 'get' operation on the MCH's
- * device/functions we want to reference for this driver
+/**
+ * i7300_get_devices() - Find and perform 'get' operation on the MCH's
+ * device/functions we want to reference for this driver
+ * @mci: struct mem_ctl_info pointer
*
- * Need to 'get' device 16 func 1 and func 2
+ * Access and prepare the several devices for usage:
+ * I7300 devices used by this driver:
+ * Device 16, functions 0,1 and 2: PCI_DEVICE_ID_INTEL_I7300_MCH_ERR
+ * Device 21 function 0: PCI_DEVICE_ID_INTEL_I7300_MCH_FB0
+ * Device 22 function 0: PCI_DEVICE_ID_INTEL_I7300_MCH_FB1
*/
-static int i7300_get_devices(struct mem_ctl_info *mci, int dev_idx)
+static int __devinit i7300_get_devices(struct mem_ctl_info *mci)
{
struct i7300_pvt *pvt;
struct pci_dev *pdev;
@@ -1007,23 +1019,25 @@ error:
return -ENODEV;
}
-/*
- * i7300_probe1 Probe for ONE instance of device to see if it is
- * present.
- * return:
- * 0 for FOUND a device
- * < 0 for error code
+/**
+ * i7300_init_one() - Probe for one instance of the device
+ * @pdev: struct pci_dev pointer
+ * @id: struct pci_device_id pointer - currently unused
*/
-static int i7300_probe1(struct pci_dev *pdev, int dev_idx)
+static int __devinit i7300_init_one(struct pci_dev *pdev,
+ const struct pci_device_id *id)
{
struct mem_ctl_info *mci;
struct i7300_pvt *pvt;
int num_channels;
int num_dimms_per_channel;
int num_csrows;
+ int rc;
- if (dev_idx >= ARRAY_SIZE(i7300_devs))
- return -EINVAL;
+ /* wake up device */
+ rc = pci_enable_device(pdev);
+ if (rc == -EIO)
+ return rc;
debugf0("MC: " __FILE__ ": %s(), pdev bus %u dev=0x%x fn=0x%x\n",
__func__,
@@ -1068,7 +1082,7 @@ static int i7300_probe1(struct pci_dev *pdev, int dev_idx)
}
/* 'get' the pci devices we want to reserve for our use */
- if (i7300_get_devices(mci, dev_idx))
+ if (i7300_get_devices(mci))
goto fail0;
mci->mc_idx = 0;
@@ -1077,7 +1091,7 @@ static int i7300_probe1(struct pci_dev *pdev, int dev_idx)
mci->edac_cap = EDAC_FLAG_NONE;
mci->mod_name = "i7300_edac.c";
mci->mod_ver = I7300_REVISION;
- mci->ctl_name = i7300_devs[dev_idx].ctl_name;
+ mci->ctl_name = i7300_devs[0].ctl_name;
mci->dev_name = pci_name(pdev);
mci->ctl_page_to_phys = NULL;
@@ -1132,32 +1146,9 @@ fail0:
return -ENODEV;
}
-/*
- * i7300_init_one constructor for one instance of device
- *
- * returns:
- * negative on error
- * count (>= 0)
- */
-static int __devinit i7300_init_one(struct pci_dev *pdev,
- const struct pci_device_id *id)
-{
- int rc;
-
- debugf0("MC: " __FILE__ ": %s()\n", __func__);
-
- /* wake up device */
- rc = pci_enable_device(pdev);
- if (rc == -EIO)
- return rc;
-
- /* now probe and enable the device */
- return i7300_probe1(pdev, id->driver_data);
-}
-
-/*
- * i7300_remove_one destructor for one instance of device
- *
+/**
+ * i7300_remove_one() - Remove the driver
+ * @pdev: struct pci_dev pointer
*/
static void __devexit i7300_remove_one(struct pci_dev *pdev)
{
@@ -1183,9 +1174,9 @@ static void __devexit i7300_remove_one(struct pci_dev *pdev)
}
/*
- * pci_device_id table for which devices we are looking for
+ * pci_device_id: table for which devices we are looking for
*
- * The "E500P" device is the first device supported.
+ * Has only 8086:360c PCI ID
*/
static const struct pci_device_id i7300_pci_tbl[] __devinitdata = {
{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_I7300_MCH_ERR)},
@@ -1195,8 +1186,7 @@ static const struct pci_device_id i7300_pci_tbl[] __devinitdata = {
MODULE_DEVICE_TABLE(pci, i7300_pci_tbl);
/*
- * i7300_driver pci_driver structure for this module
- *
+ * i7300_driver: pci_driver structure for this module
*/
static struct pci_driver i7300_driver = {
.name = "i7300_edac",
@@ -1205,9 +1195,8 @@ static struct pci_driver i7300_driver = {
.id_table = i7300_pci_tbl,
};
-/*
- * i7300_init Module entry function
- * Try to initialize this module for its devices
+/**
+ * i7300_init() - Registers the driver
*/
static int __init i7300_init(void)
{
@@ -1223,9 +1212,8 @@ static int __init i7300_init(void)
return (pci_rc < 0) ? pci_rc : 0;
}
-/*
- * i7300_exit() Module exit function
- * Unregister the driver
+/**
+ * i7300_init() - Unregisters the driver
*/
static void __exit i7300_exit(void)
{
