All of lore.kernel.org
 help / color / mirror / Atom feed
From: Luca Coelho <luca@coelho.fi>
To: kvalo@codeaurora.org
Cc: luca@coelho.fi, linux-wireless@vger.kernel.org
Subject: [PATCH 11/12] iwlwifi: pcie: remove TR/CR tail allocations
Date: Thu, 17 Jun 2021 10:08:51 +0300	[thread overview]
Message-ID: <iwlwifi.20210617100544.b5c639f3866f.I4d5de1929be048085767f1234a1e07b517ab6a2d@changeid> (raw)
In-Reply-To: <20210617070852.496985-1-luca@coelho.fi>

From: Johannes Berg <johannes.berg@intel.com>

The TR/CR tail data are meant to be per-queue-arrays, however,
we allocate them completely wrong (we have a separate allocation
per queue).

Looking at this more closely, it turns out that the hardware
never uses these - we have a separate free list per RX queue
and maintain a write pointer for that in a register, and the
RX itself is indicated in the RB status (rb_stts) DMA region.

Therefore, remove the TR/CR tail allocations completely.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
---
 .../intel/iwlwifi/pcie/ctxt-info-gen3.c       | 28 +++++++--------
 .../wireless/intel/iwlwifi/pcie/internal.h    | 11 ------
 drivers/net/wireless/intel/iwlwifi/pcie/rx.c  | 34 -------------------
 3 files changed, 14 insertions(+), 59 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c b/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c
index cecc32e7dbe8..49560e508b5e 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c
@@ -138,8 +138,15 @@ int iwl_pcie_ctxt_info_gen3_init(struct iwl_trans *trans,
 
 	/* Allocate prph information
 	 * currently we don't assign to the prph info anything, but it would get
-	 * assigned later */
-	prph_info = dma_alloc_coherent(trans->dev, sizeof(*prph_info),
+	 * assigned later
+	 *
+	 * We also use the second half of this page to give the device some
+	 * dummy TR/CR tail pointers - which shouldn't be necessary as we don't
+	 * use this, but the hardware still reads/writes there and we can't let
+	 * it go do that with a NULL pointer.
+	 */
+	BUILD_BUG_ON(sizeof(*prph_info) > PAGE_SIZE / 2);
+	prph_info = dma_alloc_coherent(trans->dev, PAGE_SIZE,
 				       &trans_pcie->prph_info_dma_addr,
 				       GFP_KERNEL);
 	if (!prph_info) {
@@ -166,13 +173,9 @@ int iwl_pcie_ctxt_info_gen3_init(struct iwl_trans *trans,
 	ctxt_info_gen3->cr_head_idx_arr_base_addr =
 		cpu_to_le64(trans_pcie->rxq->rb_stts_dma);
 	ctxt_info_gen3->tr_tail_idx_arr_base_addr =
-		cpu_to_le64(trans_pcie->rxq->tr_tail_dma);
+		cpu_to_le64(trans_pcie->prph_info_dma_addr + PAGE_SIZE / 2);
 	ctxt_info_gen3->cr_tail_idx_arr_base_addr =
-		cpu_to_le64(trans_pcie->rxq->cr_tail_dma);
-	ctxt_info_gen3->cr_idx_arr_size =
-		cpu_to_le16(IWL_NUM_OF_COMPLETION_RINGS);
-	ctxt_info_gen3->tr_idx_arr_size =
-		cpu_to_le16(IWL_NUM_OF_TRANSFER_RINGS);
+		cpu_to_le64(trans_pcie->prph_info_dma_addr + 3 * PAGE_SIZE / 4);
 	ctxt_info_gen3->mtr_base_addr =
 		cpu_to_le64(trans->txqs.txq[trans->txqs.cmd.q_id]->dma_addr);
 	ctxt_info_gen3->mcr_base_addr =
@@ -216,10 +219,8 @@ int iwl_pcie_ctxt_info_gen3_init(struct iwl_trans *trans,
 			  trans_pcie->ctxt_info_dma_addr);
 	trans_pcie->ctxt_info_gen3 = NULL;
 err_free_prph_info:
-	dma_free_coherent(trans->dev,
-			  sizeof(*prph_info),
-			prph_info,
-			trans_pcie->prph_info_dma_addr);
+	dma_free_coherent(trans->dev, PAGE_SIZE, prph_info,
+			  trans_pcie->prph_info_dma_addr);
 
 err_free_prph_scratch:
 	dma_free_coherent(trans->dev,
@@ -251,8 +252,7 @@ void iwl_pcie_ctxt_info_gen3_free(struct iwl_trans *trans)
 	trans_pcie->prph_scratch_dma_addr = 0;
 	trans_pcie->prph_scratch = NULL;
 
-	dma_free_coherent(trans->dev, sizeof(*trans_pcie->prph_info),
-			  trans_pcie->prph_info,
+	dma_free_coherent(trans->dev, PAGE_SIZE, trans_pcie->prph_info,
 			  trans_pcie->prph_info_dma_addr);
 	trans_pcie->prph_info_dma_addr = 0;
 	trans_pcie->prph_info = NULL;
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
index 1c740c382b9b..292b972a25db 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
@@ -111,10 +111,6 @@ struct iwl_rx_completion_desc {
  * @bd_dma: bus address of buffer of receive buffer descriptors (rbd)
  * @used_bd: driver's pointer to buffer of used receive buffer descriptors (rbd)
  * @used_bd_dma: physical address of buffer of used receive buffer descriptors (rbd)
- * @tr_tail: driver's pointer to the transmission ring tail buffer
- * @tr_tail_dma: physical address of the buffer for the transmission ring tail
- * @cr_tail: driver's pointer to the completion ring tail buffer
- * @cr_tail_dma: physical address of the buffer for the completion ring tail
  * @read: Shared index to newest available Rx buffer
  * @write: Shared index to oldest written Rx packet
  * @free_count: Number of pre-allocated buffers in rx_free
@@ -142,10 +138,6 @@ struct iwl_rxq {
 		struct iwl_rx_completion_desc *cd;
 	};
 	dma_addr_t used_bd_dma;
-	__le16 *tr_tail;
-	dma_addr_t tr_tail_dma;
-	__le16 *cr_tail;
-	dma_addr_t cr_tail_dma;
 	u32 read;
 	u32 write;
 	u32 free_count;
@@ -533,9 +525,6 @@ static inline void _iwl_disable_interrupts(struct iwl_trans *trans)
 	IWL_DEBUG_ISR(trans, "Disabled interrupts\n");
 }
 
-#define IWL_NUM_OF_COMPLETION_RINGS	31
-#define IWL_NUM_OF_TRANSFER_RINGS	527
-
 static inline int iwl_pcie_get_num_sections(const struct fw_img *fw,
 					    int start)
 {
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
index fb8491412be4..4f6f4b2720f0 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/rx.c
@@ -663,7 +663,6 @@ static int iwl_pcie_free_bd_size(struct iwl_trans *trans, bool use_rx_td)
 static void iwl_pcie_free_rxq_dma(struct iwl_trans *trans,
 				  struct iwl_rxq *rxq)
 {
-	struct device *dev = trans->dev;
 	bool use_rx_td = (trans->trans_cfg->device_family >=
 			  IWL_DEVICE_FAMILY_AX210);
 	int free_size = iwl_pcie_free_bd_size(trans, use_rx_td);
@@ -685,21 +684,6 @@ static void iwl_pcie_free_rxq_dma(struct iwl_trans *trans,
 				  rxq->used_bd, rxq->used_bd_dma);
 	rxq->used_bd_dma = 0;
 	rxq->used_bd = NULL;
-
-	if (trans->trans_cfg->device_family < IWL_DEVICE_FAMILY_AX210)
-		return;
-
-	if (rxq->tr_tail)
-		dma_free_coherent(dev, sizeof(__le16),
-				  rxq->tr_tail, rxq->tr_tail_dma);
-	rxq->tr_tail_dma = 0;
-	rxq->tr_tail = NULL;
-
-	if (rxq->cr_tail)
-		dma_free_coherent(dev, sizeof(__le16),
-				  rxq->cr_tail, rxq->cr_tail_dma);
-	rxq->cr_tail_dma = 0;
-	rxq->cr_tail = NULL;
 }
 
 static int iwl_pcie_alloc_rxq_dma(struct iwl_trans *trans,
@@ -744,21 +728,6 @@ static int iwl_pcie_alloc_rxq_dma(struct iwl_trans *trans,
 	rxq->rb_stts_dma =
 		trans_pcie->base_rb_stts_dma + rxq->id * rb_stts_size;
 
-	if (!use_rx_td)
-		return 0;
-
-	/* Allocate the driver's pointer to TR tail */
-	rxq->tr_tail = dma_alloc_coherent(dev, sizeof(__le16),
-					  &rxq->tr_tail_dma, GFP_KERNEL);
-	if (!rxq->tr_tail)
-		goto err;
-
-	/* Allocate the driver's pointer to CR tail */
-	rxq->cr_tail = dma_alloc_coherent(dev, sizeof(__le16),
-					  &rxq->cr_tail_dma, GFP_KERNEL);
-	if (!rxq->cr_tail)
-		goto err;
-
 	return 0;
 
 err:
@@ -1590,9 +1559,6 @@ static int iwl_pcie_rx_handle(struct iwl_trans *trans, int queue, int budget)
 out:
 	/* Backtrack one entry */
 	rxq->read = i;
-	/* update cr tail with the rxq read pointer */
-	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210)
-		*rxq->cr_tail = cpu_to_le16(r);
 	spin_unlock(&rxq->lock);
 
 	/*
-- 
2.32.0


  parent reply	other threads:[~2021-06-17  7:11 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-17  7:08 [PATCH 00/12] iwlwifi: updates intended for v5.14 2021-06-17 Luca Coelho
2021-06-17  7:08 ` [PATCH 01/12] iwlwifi: pcie: identify the RF module Luca Coelho
2021-06-17  7:08 ` [PATCH 02/12] iwlwifi: mvm: don't request SMPS in AP mode Luca Coelho
2021-06-17  7:08 ` [PATCH 03/12] iwlwifi: mvm: apply RX diversity per PHY context Luca Coelho
2021-06-17  7:08 ` [PATCH 04/12] iwlwifi: mvm: honour firmware SMPS requests Luca Coelho
2021-06-17  7:08 ` [PATCH 05/12] iwlwifi: mvm: fix error print when session protection ends Luca Coelho
2021-06-17  7:08 ` [PATCH 06/12] iwlwifi: mvm: Call NMI instead of REPLY_ERROR Luca Coelho
2021-06-17  7:08 ` [PATCH 07/12] iwlwifi: correct HE capabilities Luca Coelho
2021-06-17  7:08 ` [PATCH 08/12] iwlwifi: mvm: support LMR feedback Luca Coelho
2021-06-17  7:08 ` [PATCH 09/12] iwlwifi: advertise broadcast TWT support Luca Coelho
2021-06-22 12:19   ` Luca Coelho
2021-06-17  7:08 ` [PATCH 10/12] iwlwifi: pcie: fix some kernel-doc comments Luca Coelho
2021-06-17  7:08 ` Luca Coelho [this message]
2021-06-17  7:43   ` [PATCH 11/12] iwlwifi: pcie: remove TR/CR tail allocations Johannes Berg
2021-06-17  8:07     ` [PATCH v2 " Luca Coelho
2021-06-22 12:20       ` Luca Coelho
2021-06-17  7:08 ` [PATCH 12/12] iwlwifi: mvm: Read acpi dsm to get unii4 enable/disable bitmap Luca Coelho
2021-06-22 12:21   ` Luca Coelho

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=iwlwifi.20210617100544.b5c639f3866f.I4d5de1929be048085767f1234a1e07b517ab6a2d@changeid \
    --to=luca@coelho.fi \
    --cc=kvalo@codeaurora.org \
    --cc=linux-wireless@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.