On Mon, Sep 09, 2024 at 11:21:24AM +0800, Zhao Qunqin wrote:
> Subject: Re: [PATCH v4 2/2] Loongarch: EDAC driver for loongson memory controller
EDAC/loongson: Add EDAC driver ...
> Reports single bit errors (CE) only.
>
> Signed-off-by: Zhao Qunqin <zhaoqunqin@xxxxxxxxxxx>
> ---
...
> diff --git a/drivers/edac/loongson_edac.c b/drivers/edac/loongson_edac.c
> new file mode 100644
> index 000000000..b89d6e0e7
> --- /dev/null
> +++ b/drivers/edac/loongson_edac.c
> @@ -0,0 +1,182 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2024 Loongson Technology Corporation Limited.
> + */
> +
> +#include <linux/edac.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/platform_device.h>
> +
> +#include "edac_module.h"
> +
> +enum ecc_index {
> + ECC_SET = 0,
> + ECC_RESERVED,
> + ECC_COUNT,
> + ECC_CS_COUNT,
> + ECC_CODE,
> + ECC_ADDR,
> + ECC_DATA0,
> + ECC_DATA1,
> + ECC_DATA2,
> + ECC_DATA3,
> +};
> +
> +struct loongson_edac_pvt {
> + u64 *ecc_base;
> + int last_ce_count;
> +};
> +
> +static void loongson_update_ce_count(struct mem_ctl_info *mci,
Drop the loongson_ prefix from all static functions.
Also, align function arguments on the opening brace.
> + int chan,
> + int new)
> +{
> + int add;
> + struct loongson_edac_pvt *pvt = mci->pvt_info;
The EDAC tree preferred ordering of variable declarations at the
beginning of a function is reverse fir tree order::
struct long_struct_name *descriptive_name;
unsigned long foo, bar;
unsigned int tmp;
int ret;
The above is faster to parse than the reverse ordering::
int ret;
unsigned int tmp;
unsigned long foo, bar;
struct long_struct_name *descriptive_name;
And even more so than random ordering::
unsigned long foo, bar;
int ret;
struct long_struct_name *descriptive_name;
unsigned int tmp;
> +
> + add = new - pvt->last_ce_count;
> +
> + /* Store the new value */
Drop all those obvious comments.
> + pvt->last_ce_count = new;
> +
> + /* device resume or any other exceptions*/
No clue what that means.
Also, the check goes right under the assignment.
> + if (add < 0)
> + return;
> +
> + /*updated the edac core */
Useless comment.
> + if (add != 0) {
if (!add)
return;
and now you can save yourself an indentation level:
edac_mc_...(
> + edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, add,
> + 0, 0, 0,
> + chan, 0, -1, "error", "");
> + edac_mc_printk(mci, KERN_INFO, "add: %d", add);
> + }
> +}
> +
> +static int loongson_read_ecc(struct mem_ctl_info *mci)
> +{
> + u64 ecc;
> + int cs = 0;
> + struct loongson_edac_pvt *pvt = mci->pvt_info;
> +
> + if (!pvt->ecc_base)
> + return pvt->last_ce_count;
> +
> + ecc = pvt->ecc_base[ECC_CS_COUNT];
> + cs += ecc & 0xff; // cs0
> + cs += (ecc >> 8) & 0xff; // cs1
> + cs += (ecc >> 16) & 0xff; // cs2
> + cs += (ecc >> 24) & 0xff; // cs3
No side comments pls - put them over the line.
> +
> + return cs;
> +}
> +
> +static void loongson_edac_check(struct mem_ctl_info *mci)
> +{
> + loongson_update_ce_count(mci, 0, loongson_read_ecc(mci));
Drop this silly wrapper.
> +}
> +
> +static int get_dimm_config(struct mem_ctl_info *mci)
> +{
> + u32 size, npages;
> + struct dimm_info *dimm;
> +
> + /* size not used */
> + size = -1;
> + npages = MiB_TO_PAGES(size);
> +
> + dimm = edac_get_dimm(mci, 0, 0, 0);
> + dimm->nr_pages = npages;
> + snprintf(dimm->label, sizeof(dimm->label),
> + "MC#%uChannel#%u_DIMM#%u",
> + mci->mc_idx, 0, 0);
Align arguments on the opening brace.
> + dimm->grain = 8;
> +
> + return 0;
> +}
...
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
