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>

4 files changed, 257 insertions, 0 deletions

diff --git a/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf.host.c b/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf.host.c
new file mode 100644
index 0000000..ab75625
--- /dev/null
+++ b/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf.host.c
@@ -0,0 +1,141 @@
+/*
+ * Support for Intel Camera Imaging ISP subsystem.
+ * Copyright (c) 2015, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#include "ia_css_vf.host.h"
+#include <assert_support.h>
+#include <ia_css_err.h>
+#include <ia_css_frame.h>
+#include <ia_css_frame_public.h>
+#include <ia_css_pipeline.h>
+#define IA_CSS_INCLUDE_CONFIGURATIONS
+#include "ia_css_isp_configs.h"
+#include <assert_support.h>
+
+#include "isp.h"
+
+void
+ia_css_vf_config(
+	struct sh_css_isp_vf_isp_config      *to,
+	const struct ia_css_vf_configuration *from,
+	unsigned size)
+{
+	unsigned elems_a = ISP_VEC_NELEMS;
+
+	(void)size;
+	to->vf_downscale_bits = from->vf_downscale_bits;
+	to->enable = from->info != NULL;
+
+	if (from->info) {
+		ia_css_frame_info_to_frame_sp_info(&to->info, from->info);
+		ia_css_dma_configure_from_info(&to->dma.port_b, from->info);
+		to->dma.width_a_over_b = elems_a / to->dma.port_b.elems;
+
+		/* Assume divisiblity here, may need to generalize to fixed point. */
+		assert (elems_a % to->dma.port_b.elems == 0);
+	}
+}
+
+/* compute the log2 of the downscale factor needed to get closest
+ * to the requested viewfinder resolution on the upper side. The output cannot
+ * be smaller than the requested viewfinder resolution.
+ */
+enum ia_css_err
+sh_css_vf_downscale_log2(
+	const struct ia_css_frame_info *out_info,
+	const struct ia_css_frame_info *vf_info,
+	unsigned int *downscale_log2)
+{
+       unsigned int ds_log2 = 0;
+       unsigned int out_width;
+
+       if ((out_info == NULL) | (vf_info == NULL))
+	       return IA_CSS_ERR_INVALID_ARGUMENTS;
+
+       out_width = out_info->res.width;
+
+       if (out_width == 0)
+	       return IA_CSS_ERR_INVALID_ARGUMENTS;
+
+       /* downscale until width smaller than the viewfinder width. We don't
+	* test for the height since the vmem buffers only put restrictions on
+	* the width of a line, not on the number of lines in a frame.
+	*/
+       while (out_width >= vf_info->res.width) {
+	       ds_log2++;
+	       out_width /= 2;
+       }
+       /* now width is smaller, so we go up one step */
+       if ((ds_log2 > 0) && (out_width < ia_css_binary_max_vf_width()))
+	       ds_log2--;
+       /* TODO: use actual max input resolution of vf_pp binary */
+       if ((out_info->res.width >> ds_log2) >= 2 * ia_css_binary_max_vf_width())
+	       return IA_CSS_ERR_INVALID_ARGUMENTS;
+       *downscale_log2 = ds_log2;
+       return IA_CSS_SUCCESS;
+}
+
+static enum ia_css_err
+configure_kernel(
+	const struct ia_css_binary_info *info,
+	const struct ia_css_frame_info *out_info,
+	const struct ia_css_frame_info *vf_info,
+	unsigned int *downscale_log2,
+	struct ia_css_vf_configuration *config)
+{
+       enum ia_css_err err;
+       unsigned vf_log_ds = 0;
+
+       /* First compute value */
+       if (vf_info) {
+	       err = sh_css_vf_downscale_log2(out_info, vf_info, &vf_log_ds);
+	       if (err != IA_CSS_SUCCESS)
+		       return err;
+       }
+       vf_log_ds = min(vf_log_ds, info->vf_dec.max_log_downscale);
+       *downscale_log2 = vf_log_ds;
+
+       /* Then store it in isp config section */
+       config->vf_downscale_bits = vf_log_ds;
+       return IA_CSS_SUCCESS;
+}
+
+static void
+configure_dma(
+	struct ia_css_vf_configuration *config,
+	const struct ia_css_frame_info *vf_info)
+{
+	config->info = vf_info;
+}
+
+enum ia_css_err
+ia_css_vf_configure(
+	const struct ia_css_binary *binary,
+	const struct ia_css_frame_info *out_info,
+	struct ia_css_frame_info *vf_info,
+	unsigned int *downscale_log2)
+{
+	enum ia_css_err err;
+	struct ia_css_vf_configuration config;
+	const struct ia_css_binary_info *info = &binary->info->sp;
+
+	err = configure_kernel(info, out_info, vf_info, downscale_log2, &config);
+	configure_dma(&config, vf_info);
+	if (binary) {
+		if (vf_info)
+			vf_info->raw_bit_depth = info->dma.vfdec_bits_per_pixel;
+		ia_css_configure_vf (binary, &config);
+	}
+	return IA_CSS_SUCCESS;
+}
+
diff --git a/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf.host.h b/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf.host.h
new file mode 100644
index 0000000..c7c3625
--- /dev/null
+++ b/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf.host.h
@@ -0,0 +1,47 @@
+/*
+ * Support for Intel Camera Imaging ISP subsystem.
+ * Copyright (c) 2015, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#ifndef __IA_CSS_VF_HOST_H
+#define __IA_CSS_VF_HOST_H
+
+#include "ia_css_frame_public.h"
+#include "ia_css_binary.h"
+
+#include "ia_css_vf_types.h"
+#include "ia_css_vf_param.h"
+
+/* compute the log2 of the downscale factor needed to get closest
+ * to the requested viewfinder resolution on the upper side. The output cannot
+ * be smaller than the requested viewfinder resolution.
+ */
+enum ia_css_err
+sh_css_vf_downscale_log2(
+	const struct ia_css_frame_info *out_info,
+	const struct ia_css_frame_info *vf_info,
+	unsigned int *downscale_log2);
+
+void
+ia_css_vf_config(
+	struct sh_css_isp_vf_isp_config *to,
+	const struct ia_css_vf_configuration *from,
+	unsigned size);
+
+enum ia_css_err
+ia_css_vf_configure(
+	const struct ia_css_binary *binary,
+	const struct ia_css_frame_info *out_info,
+	struct ia_css_frame_info *vf_info,
+	unsigned int *downscale_log2);
+
+#endif /* __IA_CSS_VF_HOST_H */
diff --git a/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf_param.h b/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf_param.h
new file mode 100644
index 0000000..df5d37c
--- /dev/null
+++ b/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf_param.h
@@ -0,0 +1,37 @@
+/*
+ * Support for Intel Camera Imaging ISP subsystem.
+ * Copyright (c) 2015, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#ifndef __IA_CSS_VF_PARAM_H
+#define __IA_CSS_VF_PARAM_H
+
+#include "type_support.h"
+#include "dma.h"
+#include "gc/gc_1.0/ia_css_gc_param.h" /* GAMMA_OUTPUT_BITS */
+#include "ia_css_frame_comm.h" /* ia_css_frame_sp_info */
+#include "ia_css_vf_types.h"
+
+#define VFDEC_BITS_PER_PIXEL	GAMMA_OUTPUT_BITS
+
+/** Viewfinder decimation */
+struct sh_css_isp_vf_isp_config {
+	uint32_t vf_downscale_bits; /**< Log VF downscale value */
+	uint32_t enable;
+	struct ia_css_frame_sp_info info;
+	struct {
+		uint32_t width_a_over_b;
+		struct dma_port_config port_b;
+	} dma;
+};
+
+#endif /* __IA_CSS_VF_PARAM_H */
diff --git a/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf_types.h b/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf_types.h
new file mode 100644
index 0000000..d8cfdfb
--- /dev/null
+++ b/drivers/staging/media/atomisp/pci/atomisp2/css2400/isp/kernels/vf/vf_1.0/ia_css_vf_types.h
@@ -0,0 +1,32 @@
+/*
+ * Support for Intel Camera Imaging ISP subsystem.
+ * Copyright (c) 2015, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#ifndef __IA_CSS_VF_TYPES_H
+#define __IA_CSS_VF_TYPES_H
+
+/** Viewfinder decimation
+ *
+ *  ISP block: vfeven_horizontal_downscale
+ */
+
+#include <ia_css_frame_public.h>
+#include <type_support.h>
+
+struct ia_css_vf_configuration {
+	uint32_t vf_downscale_bits; /**< Log VF downscale value */
+	const struct ia_css_frame_info *info;
+};
+
+#endif /* __IA_CSS_VF_TYPES_H */
+