On Fri, Jan 25, 2019 at 05:52:57PM +0100, Geert Uytterhoeven wrote:
> Perform some basic sanity checks on all built-in pinmux tables when
> DEBUG is defined, to help catching bugs early.
>
> For now the following checks are included:
> - Check register and field widths in descriptors for config registers
> with variable-width fields,
> - Check relations between pin groups and functions:
> - All pin functions must refer to existing pin groups,
> - All pin groups must be referred to by a pin function,
> - Warn if a pin group is referred to by multiple pin functions
> (which is OK for backwards-compatibility aliases),
> - Provide suggestions for reducing table sizes: reserved fields of
> more than 3 bits can better be split in smaller subfields, as the
> storage need is proportional to the square of the width of the
> (sub)field,
>
> Note that a dummy non-matching entry is added to the DT match table for
> checking r8a7795es1_pinmux_info, as R-Car H3 ES1.0 is matched using
> soc_device_match() in r8a7795_pinmux_init(), instead of by the DT match
> table.
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Hi Geert,
I noted a few nits below, but in writing them I got to feel
that perhaps its just me not appreciating the merit of
some of the idioms used. So feel free to ignore them.
Nits aside,
Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
> ---
> v2:
> - Drop RFC state,
> - Drop validation of fixed-with config register fields, as this is now
> done at build time,
> - Check relations between pin groups and functions,
> - Move compile-test support out,
> - Move checks depending on enum ID absorption out,
> - Move call to sh_pfc_check_driver() from sh_pfc_probe() to
> sh_pfc_init(), so the checks are even performed on non-native
> platforms when compile-testing.
> ---
> drivers/pinctrl/sh-pfc/core.c | 123 ++++++++++++++++++++++++++++++++++
> 1 file changed, 123 insertions(+)
>
> diff --git a/drivers/pinctrl/sh-pfc/core.c b/drivers/pinctrl/sh-pfc/core.c
> index f1cfcc8c65446662..f9371e160872f2b4 100644
> --- a/drivers/pinctrl/sh-pfc/core.c
> +++ b/drivers/pinctrl/sh-pfc/core.c
> @@ -571,6 +571,13 @@ static const struct of_device_id sh_pfc_of_table[] = {
> .compatible = "renesas,pfc-r8a7795",
> .data = &r8a7795_pinmux_info,
> },
> +#ifdef DEBUG
> + {
> + /* For sanity checks only (nothing matches against this) */
> + .compatible = "renesas,pfc-r8a77950", /* R-Car H3 ES1.0 */
> + .data = &r8a7795es1_pinmux_info,
> + },
> +#endif /* DEBUG */
> #endif
> #ifdef CONFIG_PINCTRL_PFC_R8A7796
> {
> @@ -709,6 +716,121 @@ static int sh_pfc_suspend_init(struct sh_pfc *pfc) { return 0; }
> #define DEV_PM_OPS NULL
> #endif /* CONFIG_PM_SLEEP && CONFIG_ARM_PSCI_FW */
>
> +#ifdef DEBUG
> +static bool is0s(const u16 *enum_ids, unsigned int n)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < n; i++)
> + if (enum_ids[i])
> + return false;
> +
> + return true;
> +}
> +
> +static unsigned int sh_pfc_errors;
> +static unsigned int sh_pfc_warnings;
> +
> +static void sh_pfc_check_cfg_reg(const char *drvname,
> + const struct pinmux_cfg_reg *cfg_reg)
> +{
> + unsigned int i, n, rw, fw;
> +
> + if (cfg_reg->field_width) {
> + /* Checked at build time */
> + return;
> + }
> +
> + for (i = 0, n = 0, rw = 0; (fw = cfg_reg->var_field_width[i]); i++) {
nit: The assignment in the conditional expression in the for loop is
perhaps not the clearest way to express this, and its
not clear that the parentheses are required.
> + if (fw > 3 && is0s(&cfg_reg->enum_ids[n], 1 << fw)) {
> + pr_warn("%s: reg 0x%x: reserved field [%u:%u] can be split to reduce table size\n",
> + drvname, cfg_reg->reg, rw, rw + fw - 1);
> + sh_pfc_warnings++;
> + }
> + n += 1 << fw;
> + rw += fw;
> + }
> +
> + if (rw != cfg_reg->reg_width) {
> + pr_err("%s: reg 0x%x: var_field_width declares %u instead of %u bits\n",
> + drvname, cfg_reg->reg, rw, cfg_reg->reg_width);
> + sh_pfc_errors++;
> + }
> +}
> +
> +static void sh_pfc_check_info(const struct sh_pfc_soc_info *info)
> +{
> + const struct sh_pfc_function *func;
> + const char *drvname = info->name;
> + unsigned int *refcnts;
> + unsigned int i, j, k;
> +
> + pr_info("Checking %s\n", drvname);
> +
> + /* Check groups and functions */
> + refcnts = kcalloc(info->nr_groups, sizeof(*refcnts), GFP_KERNEL);
> + if (!refcnts)
> + return;
> +
> + for (i = 0; func = &info->functions[i], i < info->nr_functions; i++) {
nit: It might be clearer to set (and declare) func inside the loop.
> + for (j = 0; j < func->nr_groups; j++) {
> + for (k = 0; k < info->nr_groups; k++) {
> + if (!strcmp(func->groups[j],
> + info->groups[k].name)) {
> + refcnts[k]++;
> + goto next;
nit: goto
> + }
> + }
> +
> + pr_err("%s: function %s: group %s not found\n",
> + drvname, func->name, func->groups[j]);
> + sh_pfc_errors++;
> +
> +next: ;
> + }
> + }
> +
> + for (i = 0; i < info->nr_groups; i++) {
> + if (!refcnts[i]) {
> + pr_err("%s: orphan group %s\n", drvname,
> + info->groups[i].name);
> + sh_pfc_errors++;
> + } else if (refcnts[i] > 1) {
> + pr_err("%s: group %s referred by %u functions\n",
> + drvname, info->groups[i].name, refcnts[i]);
> + sh_pfc_warnings++;
> + }
> + }
> +
> + kfree(refcnts);
> +
> + /* Check config register descriptions */
> + for (i = 0; info->cfg_regs && info->cfg_regs[i].reg; i++)
> + sh_pfc_check_cfg_reg(drvname, &info->cfg_regs[i]);
> +}
> +
> +static void sh_pfc_check_driver(const struct platform_driver *pdrv)
> +{
> + unsigned int i;
> +
> + pr_warn("Checking builtin pinmux tables\n");
> +
> + for (i = 0; pdrv->id_table[i].name[0]; i++)
> + sh_pfc_check_info((void *)pdrv->id_table[i].driver_data);
> +
> +#ifdef CONFIG_OF
> + for (i = 0; pdrv->driver.of_match_table[i].compatible[0]; i++)
> + sh_pfc_check_info(pdrv->driver.of_match_table[i].data);
> +#endif
> +
> + pr_warn("Detected %u errors and %u warnings\n", sh_pfc_errors,
> + sh_pfc_warnings);
> +}
> +
> +#else /* !DEBUG */
> +static inline void sh_pfc_check_driver(struct platform_driver *pdrv) {}
> +#endif /* !DEBUG */
> +
> static int sh_pfc_probe(struct platform_device *pdev)
> {
> #ifdef CONFIG_OF
> @@ -840,6 +962,7 @@ static struct platform_driver sh_pfc_driver = {
>
> static int __init sh_pfc_init(void)
> {
> + sh_pfc_check_driver(&sh_pfc_driver);
> return platform_driver_register(&sh_pfc_driver);
> }
> postcore_initcall(sh_pfc_init);
> --
> 2.17.1
>
