[PATCH] wifi: ath11k: fix ce memory mapping for ahb devices

[Raj Kumar Bhagat]

Currently ath11k_ahb module is not loaded successfully and the wifi
interface is not created. Kernel trace is seen while loading the
ath11k_ahb module. The issue is seen in all ath11k AHB devices except
in IPQ5018.

This happens because in ath11k_ahb_probe(), ab->mem_ce is initialized
with the value of ab->mem. However, at this instant ab->mem is not
yet set.

Later, during write to a particular memory via ath11k_ahb_write32()
this ab->mem_ce is used with particular offset. Since ab->mem_ce is
not set properly this possibly leads to memory conflict to handle
kernel paging request and the below trace is seen.

[   93.035047] Unable to handle kernel paging request at virtual address ffff800100a00000
[   93.035083] Mem abort info:
[   93.041869]   ESR = 0x0000000096000045
[   93.044561]   EC = 0x25: DABT (current EL), IL = 32 bits
[   93.048377]   SET = 0, FnV = 0
[   93.053840]   EA = 0, S1PTW = 0
[   93.056704]   FSC = 0x05: level 1 translation fault
[   93.059745] Data abort info:
[   93.064603]   ISV = 0, ISS = 0x00000045
[   93.067729]   CM = 0, WnR = 1
[   93.071287] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000042219000
[   93.074409] [ffff800100a00000] pgd=100000007ffff003, p4d=100000007ffff003, pud=0000000000000000
[   93.081195] Internal error: Oops: 0000000096000045 [#1] PREEMPT SMP
[   93.089598] Modules linked in: ath11k_ahb ath11k_pci ath11k qmi_helpers
[   93.095851] CPU: 2 PID: 66 Comm: kworker/u8:3 Not tainted 6.1.0-rc8-wt-ath-658126-g58e4b9df840c-dirty #2
[   93.102454] Hardware name: Qualcomm Technologies, Inc. IPQ8074/AP-HK14 (DT)
[   93.112171] Workqueue: ath11k_qmi_driver_event ath11k_qmi_driver_event_work [ath11k]
[   93.118856] pstate: 40000005 (nZcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[   93.126838] pc : ath11k_ahb_write32+0xc/0x18 [ath11k_ahb]
[   93.133520] lr : ath11k_hal_srng_setup+0x860/0x8f0 [ath11k]
[   93.139075] sp : ffff80000aaebb70
[   93.144452] x29: ffff80000aaebb70 x28: 0000000000000020 x27: ffff80000aaebc50
[   93.147934] x26: ffff000004923750 x25: ffff000004921200 x24: ffff000004928000
[   93.155051] x23: 0000000000000020 x22: ffff000004930000 x21: ffff000004923200
[   93.162170] x20: ffff000004920000 x19: 00000000eea00000 x18: ffff0000049200f0
[   93.169288] x17: 0000000000000000 x16: 0000000000000000 x15: 000000000000025e
[   93.176405] x14: ffff000003c414f0 x13: 0000000000000000 x12: 0000000000000008
[   93.183524] x11: ffff000003c41488 x10: 0000000000000040 x9 : 0000000000000000
[   93.190641] x8 : ffff80000a9dd100 x7 : 0000000000000000 x6 : 000000000000003f
[   93.197759] x5 : ffff800100a00400 x4 : ffff8000031f4018 x3 : 0000000000000004
[   93.204877] x2 : 0000000047b62000 x1 : ffff800100a00000 x0 : ffff800012000000
[   93.211996] Call trace:
[   93.219104]  ath11k_ahb_write32+0xc/0x18 [ath11k_ahb]
[   93.221366]  ath11k_ce_init_ring+0x184/0x278 [ath11k]
[   93.226576]  ath11k_ce_init_pipes+0x4c/0x1a0 [ath11k]
[   93.231610]  ath11k_core_qmi_firmware_ready+0x3c/0x568 [ath11k]
[   93.236646]  ath11k_qmi_driver_event_work+0x168/0x4f8 [ath11k]
[   93.242376]  process_one_work+0x144/0x350
[   93.248275]  worker_thread+0x120/0x430
[   93.252352]  kthread+0xf4/0x110
[   93.255997]  ret_from_fork+0x10/0x20
[   93.259043] Code: d503201f f94e1c00 8b214001 d50332bf (b9000022)
[   93.262863] ---[ end trace 0000000000000000 ]---

However, for the device IPQ5018 ath11k_hw_params .ce_remap is
defined. This parameter is used to recalculate ab->mem_ce and hence,
this issue is not seen in IPQ5018.

Hence, fix this by initializing ab->mem_ce after ab->mem is set.
ab->mem is set inside the ath11k_ahb_setup_resources() therefore
initialize ab->mem_ce after ath11k_ahb_setup_resources().

Tested-on: IPQ8074 hw2.0 AHB WLAN.HK.2.7.0.1-01744-QCAHKSWPL_SILICONZ-1

Fixes: b42b3678c91f ("wifi: ath11k: remap ce register space for IPQ5018")

Signed-off-by: Raj Kumar Bhagat <quic_rajkbhag at quicinc.com>
---
 drivers/net/wireless/ath/ath11k/ahb.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/ahb.c b/drivers/net/wireless/ath/ath11k/ahb.c
index 085e99633951..cd48eca494ed 100644
--- a/drivers/net/wireless/ath/ath11k/ahb.c
+++ b/drivers/net/wireless/ath/ath11k/ahb.c
@@ -1157,12 +1157,16 @@ static int ath11k_ahb_probe(struct platform_device *pdev)
 		goto err_core_free;
 	}
 
-	ab->mem_ce = ab->mem;
-
 	ret = ath11k_core_pre_init(ab);
 	if (ret)
 		goto err_core_free;
 
+	ret = ath11k_ahb_setup_resources(ab);
+	if (ret)
+		goto err_core_free;
+
+	ab->mem_ce = ab->mem;
+
 	if (ab->hw_params.ce_remap) {
 		const struct ce_remap *ce_remap = ab->hw_params.ce_remap;
 		/* ce register space is moved out of wcss unlike ipq8074 or ipq6018
@@ -1177,10 +1181,6 @@ static int ath11k_ahb_probe(struct platform_device *pdev)
 		}
 	}
 
-	ret = ath11k_ahb_setup_resources(ab);
-	if (ret)
-		goto err_core_free;
-
 	ret = ath11k_ahb_fw_resources_init(ab);
 	if (ret)
 		goto err_core_free;

base-commit: e51980bf88c65f6ad4916baf720ad1234de01791
-- 
2.17.1