[PATCH] Revert "bus: ti-sysc: Probe for l4_wkup and l4_cfg interconnect devices first"

A. Sverdlin
2025-03-13T09:47:13Z

From: Alexander Sverdlin <alexander.sverdlin@siemens.com>

This reverts commit 4700a00755fb5a4bb5109128297d6fd2d1272ee6.

It brakes target-module@2b300050 ("ti,sysc-omap2") probe on AM62x in a case
when minimally-configured system tries to network-boot:

[ 6.888776] probe of 2b300050.target-module returned 517 after 258 usecs
[ 17.129637] probe of 2b300050.target-module returned 517 after 708 usecs
[ 17.137397] platform 2b300050.target-module: deferred probe pending: (reason unknown)
[ 26.878471] Waiting up to 100 more seconds for network.

Arbitrary 10 deferrals is really not a solution to any problem.
Stable mmc enumeration can be achiever by filling /aliases node properly
(4700a00755fb commit's rationale).

After revert:

[ 9.006816] IP-Config: Complete:
[ 9.010058] device=lan0, ...

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
---
drivers/bus/ti-sysc.c | 49 -------------------------------------------
1 file changed, 49 deletions(-)

diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c
index f67b927ae4caa..e5c02e950f2c1 100644
--- a/drivers/bus/ti-sysc.c
+++ b/drivers/bus/ti-sysc.c
@@ -677,51 +677,6 @@ static int sysc_parse_and_check_child_range(struct sysc *ddata)
return 0;
}

-/* Interconnect instances to probe before l4_per instances */
-static struct resource early_bus_ranges[] = {
- /* am3/4 l4_wkup */
- { .start = 0x44c00000, .end = 0x44c00000 + 0x300000, },
- /* omap4/5 and dra7 l4_cfg */
- { .start = 0x4a000000, .end = 0x4a000000 + 0x300000, },
- /* omap4 l4_wkup */
- { .start = 0x4a300000, .end = 0x4a300000 + 0x30000, },
- /* omap5 and dra7 l4_wkup without dra7 dcan segment */
- { .start = 0x4ae00000, .end = 0x4ae00000 + 0x30000, },
-};
-
-static atomic_t sysc_defer = ATOMIC_INIT(10);
-
-/**
- * sysc_defer_non_critical - defer non_critical interconnect probing
- * @ddata: device driver data
- *
- * We want to probe l4_cfg and l4_wkup interconnect instances before any
- * l4_per instances as l4_per instances depend on resources on l4_cfg and
- * l4_wkup interconnects.
- */
-static int sysc_defer_non_critical(struct sysc *ddata)
-{
- struct resource *res;
- int i;
-
- if (!atomic_read(&sysc_defer))
- return 0;
-
- for (i = 0; i < ARRAY_SIZE(early_bus_ranges); i++) {
- res = &early_bus_ranges[i];
- if (ddata->module_pa >= res->start &&
- ddata->module_pa <= res->end) {
- atomic_set(&sysc_defer, 0);
-
- return 0;
- }
- }
-
- atomic_dec_if_positive(&sysc_defer);
-
- return -EPROBE_DEFER;
-}
-
static struct device_node *stdout_path;

static void sysc_init_stdout_path(struct sysc *ddata)
@@ -947,10 +902,6 @@ static int sysc_map_and_check_registers(struct sysc *ddata)
if (error)
return error;

- error = sysc_defer_non_critical(ddata);
- if (error)
- return error;
-
sysc_check_children(ddata);

if (!of_property_present(np, "reg"))
--
2.48.1