staging/atomisp: Add support for the Intel IPU v2

This patch adds support for the Intel IPU v2 as found on Android and IoT
Baytrail-T and Baytrail-CR platforms (those with the IPU PCI mapped). You
will also need the firmware files from your device (Android usually puts
them into /etc) - or you can find them in the downloadable restore/upgrade
kits if you blew them away for some reason.

It may be possible to extend the driver to handle the BYT/T windows
platforms such as the ASUS T100TA. These platforms don't expose the IPU via
the PCI interface but via ACPI buried in the GPU description and with the
camera information somewhere unknown so would need a platform driver
interface adding to the codebase *IFF* the firmware works on such devices.

To get good results you also need a suitable support library such as
libxcam. The camera is intended to be driven from Android so it has a lot of
features that many desktop apps don't fully spport.

In theory all the pieces are there to build it with -DISP2401 and some
differing files to get CherryTrail/T support, but unifying the drivers
properlly is a work in progress.

The IPU driver represents the work of a lot of people within Intel over many
years. It's historical goal was portability rather than Linux upstream. Any
queries about the upstream aimed driver should be sent to me not to the
original authors.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 258 insertions, 0 deletions

diff --git a/drivers/staging/media/atomisp/pci/atomisp2/hmm/hmm_reserved_pool.c b/drivers/staging/media/atomisp/pci/atomisp2/hmm/hmm_reserved_pool.c
new file mode 100644
index 000000000000..590ff7bc6c5f
--- /dev/null
+++ b/drivers/staging/media/atomisp/pci/atomisp2/hmm/hmm_reserved_pool.c
@@ -0,0 +1,258 @@
+/*
+ * Support for Medifield PNW Camera Imaging ISP subsystem.
+ *
+ * Copyright (c) 2010 Intel Corporation. All Rights Reserved.
+ *
+ * Copyright (c) 2010 Silicon Hive www.siliconhive.com.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ */
+/*
+ * This file contains functions for reserved memory pool management
+ */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+
+#include "asm/cacheflush.h"
+#include "atomisp_internal.h"
+#include "hmm/hmm_pool.h"
+
+/*
+ * reserved memory pool ops.
+ */
+static unsigned int get_pages_from_reserved_pool(void *pool,
+					struct hmm_page_object *page_obj,
+					unsigned int size, bool cached)
+{
+	unsigned long flags;
+	unsigned int i = 0;
+	unsigned int repool_pgnr;
+	int j;
+	struct hmm_reserved_pool_info *repool_info = pool;
+
+	if (!repool_info)
+		return 0;
+
+	spin_lock_irqsave(&repool_info->list_lock, flags);
+	if (repool_info->initialized) {
+		repool_pgnr = repool_info->index;
+
+		for (j = repool_pgnr-1; j >= 0; j--) {
+			page_obj[i].page = repool_info->pages[j];
+			page_obj[i].type = HMM_PAGE_TYPE_RESERVED;
+			i++;
+			repool_info->index--;
+			if (i == size)
+				break;
+		}
+	}
+	spin_unlock_irqrestore(&repool_info->list_lock, flags);
+	return i;
+}
+
+static void free_pages_to_reserved_pool(void *pool,
+					struct hmm_page_object *page_obj)
+{
+	unsigned long flags;
+	struct hmm_reserved_pool_info *repool_info = pool;
+
+	if (!repool_info)
+		return;
+
+	spin_lock_irqsave(&repool_info->list_lock, flags);
+
+	if (repool_info->initialized &&
+	    repool_info->index < repool_info->pgnr &&
+	    page_obj->type == HMM_PAGE_TYPE_RESERVED) {
+		repool_info->pages[repool_info->index++] = page_obj->page;
+	}
+
+	spin_unlock_irqrestore(&repool_info->list_lock, flags);
+}
+
+static int hmm_reserved_pool_setup(struct hmm_reserved_pool_info **repool_info,
+					unsigned int pool_size)
+{
+	struct hmm_reserved_pool_info *pool_info;
+
+	pool_info = atomisp_kernel_malloc(
+					sizeof(struct hmm_reserved_pool_info));
+	if (unlikely(!pool_info)) {
+		dev_err(atomisp_dev, "out of memory for repool_info.\n");
+		return -ENOMEM;
+	}
+
+	pool_info->pages = atomisp_kernel_malloc(
+					sizeof(struct page *) * pool_size);
+	if (unlikely(!pool_info->pages)) {
+		dev_err(atomisp_dev, "out of memory for repool_info->pages.\n");
+		atomisp_kernel_free(pool_info);
+		return -ENOMEM;
+	}
+
+	pool_info->index = 0;
+	pool_info->pgnr = 0;
+	spin_lock_init(&pool_info->list_lock);
+	pool_info->initialized = true;
+
+	*repool_info = pool_info;
+
+	return 0;
+}
+
+static int hmm_reserved_pool_init(void **pool, unsigned int pool_size)
+{
+	int ret;
+	unsigned int blk_pgnr;
+	unsigned int pgnr = pool_size;
+	unsigned int order = 0;
+	unsigned int i = 0;
+	int fail_number = 0;
+	struct page *pages;
+	int j;
+	struct hmm_reserved_pool_info *repool_info;
+	if (pool_size == 0)
+		return 0;
+
+	ret = hmm_reserved_pool_setup(&repool_info, pool_size);
+	if (ret) {
+		dev_err(atomisp_dev, "hmm_reserved_pool_setup failed.\n");
+		return ret;
+	}
+
+	pgnr = pool_size;
+
+	i = 0;
+	order = MAX_ORDER;
+
+	while (pgnr) {
+		blk_pgnr = 1U << order;
+		while (blk_pgnr > pgnr) {
+			order--;
+			blk_pgnr >>= 1U;
+		}
+		BUG_ON(order > MAX_ORDER);
+
+		pages = alloc_pages(GFP_KERNEL | __GFP_NOWARN, order);
+		if (unlikely(!pages)) {
+			if (order == 0) {
+				fail_number++;
+				dev_err(atomisp_dev, "%s: alloc_pages failed: %d\n",
+						__func__, fail_number);
+				/* if fail five times, will goto end */
+
+				/* FIXME: whether is the mechanism is ok? */
+				if (fail_number == ALLOC_PAGE_FAIL_NUM)
+					goto end;
+			} else {
+				order--;
+			}
+		} else {
+			blk_pgnr = 1U << order;
+
+			ret = set_pages_uc(pages, blk_pgnr);
+			if (ret) {
+				dev_err(atomisp_dev,
+						"set pages uncached failed\n");
+				__free_pages(pages, order);
+				goto end;
+			}
+
+			for (j = 0; j < blk_pgnr; j++)
+				repool_info->pages[i++] = pages + j;
+
+			repool_info->index += blk_pgnr;
+			repool_info->pgnr += blk_pgnr;
+
+			pgnr -= blk_pgnr;
+
+			fail_number = 0;
+		}
+	}
+
+end:
+	repool_info->initialized = true;
+
+	*pool = repool_info;
+
+	dev_info(atomisp_dev,
+			"hmm_reserved_pool init successfully,"
+			"hmm_reserved_pool is with %d pages.\n",
+			repool_info->pgnr);
+	return 0;
+}
+
+static void hmm_reserved_pool_exit(void **pool)
+{
+	unsigned long flags;
+	int i, ret;
+	unsigned int pgnr;
+	struct hmm_reserved_pool_info *repool_info = *pool;
+
+	if (!repool_info)
+		return;
+
+	spin_lock_irqsave(&repool_info->list_lock, flags);
+	if (!repool_info->initialized) {
+		spin_unlock_irqrestore(&repool_info->list_lock, flags);
+		return;
+	}
+	pgnr = repool_info->pgnr;
+	repool_info->index = 0;
+	repool_info->pgnr = 0;
+	repool_info->initialized = false;
+	spin_unlock_irqrestore(&repool_info->list_lock, flags);
+
+	for (i = 0; i < pgnr; i++) {
+		ret = set_pages_wb(repool_info->pages[i], 1);
+		if (ret)
+			dev_err(atomisp_dev,
+				"set page to WB err...ret=%d\n", ret);
+		/*
+		W/A: set_pages_wb seldom return value = -EFAULT
+		indicate that address of page is not in valid
+		range(0xffff880000000000~0xffffc7ffffffffff)
+		then, _free_pages would panic; Do not know why
+		page address be valid, it maybe memory corruption by lowmemory
+		*/
+		if (!ret)
+			__free_pages(repool_info->pages[i], 0);
+	}
+
+	atomisp_kernel_free(repool_info->pages);
+	atomisp_kernel_free(repool_info);
+
+	*pool = NULL;
+}
+
+static int hmm_reserved_pool_inited(void *pool)
+{
+	struct hmm_reserved_pool_info *repool_info = pool;
+
+	if (!repool_info)
+		return 0;
+
+	return repool_info->initialized;
+}
+
+struct hmm_pool_ops reserved_pops = {
+	.pool_init		= hmm_reserved_pool_init,
+	.pool_exit		= hmm_reserved_pool_exit,
+	.pool_alloc_pages	= get_pages_from_reserved_pool,
+	.pool_free_pages	= free_pages_to_reserved_pool,
+	.pool_inited		= hmm_reserved_pool_inited,
+};