1 files changed, 375 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/wil6210/pmc.c b/drivers/net/wireless/ath/wil6210/pmc.c
new file mode 100644
index 000000000000..8a8cdc61b25b
--- /dev/null
+++ b/drivers/net/wireless/ath/wil6210/pmc.c
@@ -0,0 +1,375 @@
+/*
+ * Copyright (c) 2012-2015 Qualcomm Atheros, Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include "wmi.h"
+#include "wil6210.h"
+#include "txrx.h"
+#include "pmc.h"
+
+struct desc_alloc_info {
+	dma_addr_t pa;
+	void	  *va;
+};
+
+static int wil_is_pmc_allocated(struct pmc_ctx *pmc)
+{
+	return !!pmc->pring_va;
+}
+
+void wil_pmc_init(struct wil6210_priv *wil)
+{
+	memset(&wil->pmc, 0, sizeof(struct pmc_ctx));
+	mutex_init(&wil->pmc.lock);
+}
+
+/**
+ * Allocate the physical ring (p-ring) and the required
+ * number of descriptors of required size.
+ * Initialize the descriptors as required by pmc dma.
+ * The descriptors' buffers dwords are initialized to hold
+ * dword's serial number in the lsw and reserved value
+ * PCM_DATA_INVALID_DW_VAL in the msw.
+ */
+void wil_pmc_alloc(struct wil6210_priv *wil,
+		   int num_descriptors,
+		   int descriptor_size)
+{
+	u32 i;
+	struct pmc_ctx *pmc = &wil->pmc;
+	struct device *dev = wil_to_dev(wil);
+	struct wmi_pmc_cmd pmc_cmd = {0};
+
+	mutex_lock(&pmc->lock);
+
+	if (wil_is_pmc_allocated(pmc)) {
+		/* sanity check */
+		wil_err(wil, "%s: ERROR pmc is already allocated\n", __func__);
+		goto no_release_err;
+	}
+
+	pmc->num_descriptors = num_descriptors;
+	pmc->descriptor_size = descriptor_size;
+
+	wil_dbg_misc(wil, "%s: %d descriptors x %d bytes each\n",
+		     __func__, num_descriptors, descriptor_size);
+
+	/* allocate descriptors info list in pmc context*/
+	pmc->descriptors = kcalloc(num_descriptors,
+				  sizeof(struct desc_alloc_info),
+				  GFP_KERNEL);
+	if (!pmc->descriptors) {
+		wil_err(wil, "%s: ERROR allocating pmc skb list\n", __func__);
+		goto no_release_err;
+	}
+
+	wil_dbg_misc(wil,
+		     "%s: allocated descriptors info list %p\n",
+		     __func__, pmc->descriptors);
+
+	/* Allocate pring buffer and descriptors.
+	 * vring->va should be aligned on its size rounded up to power of 2
+	 * This is granted by the dma_alloc_coherent
+	 */
+	pmc->pring_va = dma_alloc_coherent(dev,
+			sizeof(struct vring_tx_desc) * num_descriptors,
+			&pmc->pring_pa,
+			GFP_KERNEL);
+
+	wil_dbg_misc(wil,
+		     "%s: allocated pring %p => %pad. %zd x %d = total %zd bytes\n",
+		     __func__,
+		     pmc->pring_va, &pmc->pring_pa,
+		     sizeof(struct vring_tx_desc),
+		     num_descriptors,
+		     sizeof(struct vring_tx_desc) * num_descriptors);
+
+	if (!pmc->pring_va) {
+		wil_err(wil, "%s: ERROR allocating pmc pring\n", __func__);
+		goto release_pmc_skb_list;
+	}
+
+	/* initially, all descriptors are SW owned
+	 * For Tx, Rx, and PMC, ownership bit is at the same location, thus
+	 * we can use any
+	 */
+	for (i = 0; i < num_descriptors; i++) {
+		struct vring_tx_desc *_d = &pmc->pring_va[i];
+		struct vring_tx_desc dd, *d = &dd;
+		int j = 0;
+
+		pmc->descriptors[i].va = dma_alloc_coherent(dev,
+			descriptor_size,
+			&pmc->descriptors[i].pa,
+			GFP_KERNEL);
+
+		if (unlikely(!pmc->descriptors[i].va)) {
+			wil_err(wil,
+				"%s: ERROR allocating pmc descriptor %d",
+				__func__, i);
+			goto release_pmc_skbs;
+		}
+
+		for (j = 0; j < descriptor_size / sizeof(u32); j++) {
+			u32 *p = (u32 *)pmc->descriptors[i].va + j;
+			*p = PCM_DATA_INVALID_DW_VAL | j;
+		}
+
+		/* configure dma descriptor */
+		d->dma.addr.addr_low =
+			cpu_to_le32(lower_32_bits(pmc->descriptors[i].pa));
+		d->dma.addr.addr_high =
+			cpu_to_le16((u16)upper_32_bits(pmc->descriptors[i].pa));
+		d->dma.status = 0; /* 0 = HW_OWNED */
+		d->dma.length = cpu_to_le16(descriptor_size);
+		d->dma.d0 = BIT(9) | RX_DMA_D0_CMD_DMA_IT;
+		*_d = *d;
+	}
+
+	wil_dbg_misc(wil, "%s: allocated successfully\n", __func__);
+
+	pmc_cmd.op = WMI_PMC_ALLOCATE;
+	pmc_cmd.ring_size = cpu_to_le16(pmc->num_descriptors);
+	pmc_cmd.mem_base = cpu_to_le64(pmc->pring_pa);
+
+	wil_dbg_misc(wil, "%s: send WMI_PMC_CMD with ALLOCATE op\n", __func__);
+	pmc->last_cmd_status = wmi_send(wil,
+					WMI_PMC_CMDID,
+					&pmc_cmd,
+					sizeof(pmc_cmd));
+	if (pmc->last_cmd_status) {
+		wil_err(wil,
+			"%s: WMI_PMC_CMD with ALLOCATE op failed with status %d",
+			__func__, pmc->last_cmd_status);
+		goto release_pmc_skbs;
+	}
+
+	mutex_unlock(&pmc->lock);
+
+	return;
+
+release_pmc_skbs:
+	wil_err(wil, "%s: exit on error: Releasing skbs...\n", __func__);
+	for (i = 0; pmc->descriptors[i].va && i < num_descriptors; i++) {
+		dma_free_coherent(dev,
+				  descriptor_size,
+				  pmc->descriptors[i].va,
+				  pmc->descriptors[i].pa);
+
+		pmc->descriptors[i].va = NULL;
+	}
+	wil_err(wil, "%s: exit on error: Releasing pring...\n", __func__);
+
+	dma_free_coherent(dev,
+			  sizeof(struct vring_tx_desc) * num_descriptors,
+			  pmc->pring_va,
+			  pmc->pring_pa);
+
+	pmc->pring_va = NULL;
+
+release_pmc_skb_list:
+	wil_err(wil, "%s: exit on error: Releasing descriptors info list...\n",
+		__func__);
+	kfree(pmc->descriptors);
+	pmc->descriptors = NULL;
+
+no_release_err:
+	pmc->last_cmd_status = -ENOMEM;
+	mutex_unlock(&pmc->lock);
+}
+
+/**
+ * Traverse the p-ring and release all buffers.
+ * At the end release the p-ring memory
+ */
+void wil_pmc_free(struct wil6210_priv *wil, int send_pmc_cmd)
+{
+	struct pmc_ctx *pmc = &wil->pmc;
+	struct device *dev = wil_to_dev(wil);
+	struct wmi_pmc_cmd pmc_cmd = {0};
+
+	mutex_lock(&pmc->lock);
+
+	pmc->last_cmd_status = 0;
+
+	if (!wil_is_pmc_allocated(pmc)) {
+		wil_dbg_misc(wil, "%s: Error, can't free - not allocated\n",
+			     __func__);
+		pmc->last_cmd_status = -EPERM;
+		mutex_unlock(&pmc->lock);
+		return;
+	}
+
+	if (send_pmc_cmd) {
+		wil_dbg_misc(wil, "%s: send WMI_PMC_CMD with RELEASE op\n",
+			     __func__);
+		pmc_cmd.op = WMI_PMC_RELEASE;
+		pmc->last_cmd_status =
+				wmi_send(wil, WMI_PMC_CMDID, &pmc_cmd,
+					 sizeof(pmc_cmd));
+		if (pmc->last_cmd_status) {
+			wil_err(wil,
+				"%s WMI_PMC_CMD with RELEASE op failed, status %d",
+				__func__, pmc->last_cmd_status);
+			/* There's nothing we can do with this error.
+			 * Normally, it should never occur.
+			 * Continue to freeing all memory allocated for pmc.
+			 */
+		}
+	}
+
+	if (pmc->pring_va) {
+		size_t buf_size = sizeof(struct vring_tx_desc) *
+				  pmc->num_descriptors;
+
+		wil_dbg_misc(wil, "%s: free pring va %p\n",
+			     __func__, pmc->pring_va);
+		dma_free_coherent(dev, buf_size, pmc->pring_va, pmc->pring_pa);
+
+		pmc->pring_va = NULL;
+	} else {
+		pmc->last_cmd_status = -ENOENT;
+	}
+
+	if (pmc->descriptors) {
+		int i;
+
+		for (i = 0;
+		     pmc->descriptors[i].va && i < pmc->num_descriptors; i++) {
+			dma_free_coherent(dev,
+					  pmc->descriptor_size,
+					  pmc->descriptors[i].va,
+					  pmc->descriptors[i].pa);
+			pmc->descriptors[i].va = NULL;
+		}
+		wil_dbg_misc(wil, "%s: free descriptor info %d/%d\n",
+			     __func__, i, pmc->num_descriptors);
+		wil_dbg_misc(wil,
+			     "%s: free pmc descriptors info list %p\n",
+			     __func__, pmc->descriptors);
+		kfree(pmc->descriptors);
+		pmc->descriptors = NULL;
+	} else {
+		pmc->last_cmd_status = -ENOENT;
+	}
+
+	mutex_unlock(&pmc->lock);
+}
+
+/**
+ * Status of the last operation requested via debugfs: alloc/free/read.
+ * 0 - success or negative errno
+ */
+int wil_pmc_last_cmd_status(struct wil6210_priv *wil)
+{
+	wil_dbg_misc(wil, "%s: status %d\n", __func__,
+		     wil->pmc.last_cmd_status);
+
+	return wil->pmc.last_cmd_status;
+}
+
+/**
+ * Read from required position up to the end of current descriptor,
+ * depends on descriptor size configured during alloc request.
+ */
+ssize_t wil_pmc_read(struct file *filp, char __user *buf, size_t count,
+		     loff_t *f_pos)
+{
+	struct wil6210_priv *wil = filp->private_data;
+	struct pmc_ctx *pmc = &wil->pmc;
+	size_t retval = 0;
+	unsigned long long idx;
+	loff_t offset;
+	size_t pmc_size = pmc->descriptor_size * pmc->num_descriptors;
+
+	mutex_lock(&pmc->lock);
+
+	if (!wil_is_pmc_allocated(pmc)) {
+		wil_err(wil, "%s: error, pmc is not allocated!\n", __func__);
+		pmc->last_cmd_status = -EPERM;
+		mutex_unlock(&pmc->lock);
+		return -EPERM;
+	}
+
+	wil_dbg_misc(wil,
+		     "%s: size %u, pos %lld\n",
+		     __func__, (unsigned)count, *f_pos);
+
+	pmc->last_cmd_status = 0;
+
+	idx = *f_pos;
+	do_div(idx, pmc->descriptor_size);
+	offset = *f_pos - (idx * pmc->descriptor_size);
+
+	if (*f_pos >= pmc_size) {
+		wil_dbg_misc(wil, "%s: reached end of pmc buf: %lld >= %u\n",
+			     __func__, *f_pos, (unsigned)pmc_size);
+		pmc->last_cmd_status = -ERANGE;
+		goto out;
+	}
+
+	wil_dbg_misc(wil,
+		     "%s: read from pos %lld (descriptor %llu, offset %llu) %zu bytes\n",
+		     __func__, *f_pos, idx, offset, count);
+
+	/* if no errors, return the copied byte count */
+	retval = simple_read_from_buffer(buf,
+					 count,
+					 &offset,
+					 pmc->descriptors[idx].va,
+					 pmc->descriptor_size);
+	*f_pos += retval;
+out:
+	mutex_unlock(&pmc->lock);
+
+	return retval;
+}
+
+loff_t wil_pmc_llseek(struct file *filp, loff_t off, int whence)
+{
+	loff_t newpos;
+	struct wil6210_priv *wil = filp->private_data;
+	struct pmc_ctx *pmc = &wil->pmc;
+	size_t pmc_size = pmc->descriptor_size * pmc->num_descriptors;
+
+	switch (whence) {
+	case 0: /* SEEK_SET */
+		newpos = off;
+		break;
+
+	case 1: /* SEEK_CUR */
+		newpos = filp->f_pos + off;
+		break;
+
+	case 2: /* SEEK_END */
+		newpos = pmc_size;
+		break;
+
+	default: /* can't happen */
+		return -EINVAL;
+	}
+
+	if (newpos < 0)
+		return -EINVAL;
+	if (newpos > pmc_size)
+		newpos = pmc_size;
+
+	filp->f_pos = newpos;
+
+	return newpos;
+}