Re: [PATCH V2 12/16] drm/radeon: Make radeon card usable for Loongson.

From: "j.glisse" <j.glisse@gmail.com>
To: Huacai Chen <chenhuacai@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>,
	linux-mips@linux-mips.org, Zhangjin Wu <wuzhangjin@gmail.com>,
	Hua Yan <yanh@lemote.com>, Fuxin Zhang <zhangfx@lemote.com>,
	dri-devel@lists.freedesktop.org, Hongliang Tao <taohl@lemote.com>,
	Huacai Chen <chenhc@lemote.com>
Subject: Re: [PATCH V2 12/16] drm/radeon: Make radeon card usable for Loongson.
Date: Tue, 19 Jun 2012 09:57:04 -0400	[thread overview]
Message-ID: <20120619135703.GA1979@gmail.com> (raw)
In-Reply-To: <1340088624-25550-13-git-send-email-chenhc@lemote.com>

On Tue, Jun 19, 2012 at 02:50:20PM +0800, Huacai Chen wrote:
> 1, Use 32-bit DMA as a workaround (Loongson has a hardware bug that it
>    doesn't support DMA address above 4GB).
> 2, Read vga bios offered by system firmware.
> 3, Handle io prot correctly for MIPS.
> 4, Don't use swiotlb on Loongson machines (when use swiotlb, GPU reset
>    occurs at resume from suspend).
> 
> Signed-off-by: Huacai Chen <chenhc@lemote.com>
> Signed-off-by: Hongliang Tao <taohl@lemote.com>
> Signed-off-by: Hua Yan <yanh@lemote.com>
> Cc: dri-devel@lists.freedesktop.org
> ---
>  drivers/gpu/drm/drm_vm.c               |    2 +-
>  drivers/gpu/drm/radeon/radeon_bios.c   |   32 ++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/radeon/radeon_device.c |    5 +++++
>  drivers/gpu/drm/radeon/radeon_ttm.c    |    6 +++---
>  drivers/gpu/drm/ttm/ttm_bo_util.c      |    2 +-
>  include/drm/drm_sarea.h                |    2 ++
>  6 files changed, 44 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_vm.c b/drivers/gpu/drm/drm_vm.c
> index 961ee08..3f06166 100644
> --- a/drivers/gpu/drm/drm_vm.c
> +++ b/drivers/gpu/drm/drm_vm.c
> @@ -62,7 +62,7 @@ static pgprot_t drm_io_prot(uint32_t map_type, struct vm_area_struct *vma)
>  		tmp = pgprot_writecombine(tmp);
>  	else
>  		tmp = pgprot_noncached(tmp);
> -#elif defined(__sparc__) || defined(__arm__)
> +#elif defined(__sparc__) || defined(__arm__) || defined(__mips__)
>  	tmp = pgprot_noncached(tmp);
>  #endif
>  	return tmp;
> diff --git a/drivers/gpu/drm/radeon/radeon_bios.c b/drivers/gpu/drm/radeon/radeon_bios.c
> index 501f488..2630e22 100644
> --- a/drivers/gpu/drm/radeon/radeon_bios.c
> +++ b/drivers/gpu/drm/radeon/radeon_bios.c
> @@ -29,6 +29,7 @@
>  #include "radeon_reg.h"
>  #include "radeon.h"
>  #include "atom.h"
> +#include <asm/bootinfo.h>
>  
>  #include <linux/vga_switcheroo.h>
>  #include <linux/slab.h>
> @@ -73,6 +74,32 @@ static bool igp_read_bios_from_vram(struct radeon_device *rdev)
>  	return true;
>  }
>  
> +#ifdef CONFIG_CPU_LOONGSON3
> +extern u64 vgabios_addr;

Ugly, is this how platform specific stuff are handled usualy ? I hope not,
i would rather see a platform specific function such as loongson3_get_vga_bios.

Cheers,
Jerome

> +static bool loongson3_read_bios(struct radeon_device *rdev)
> +{
> +	u8 *bios;
> +	resource_size_t size = 512 * 1024; /* ??? */
> +
> +	rdev->bios = NULL;
> +
> +	bios = (u8 *)vgabios_addr;
> +	if (!bios) {
> +		return false;
> +	}
> +
> +	if (size == 0 || bios[0] != 0x55 || bios[1] != 0xaa) {
> +		return false;
> +	}
> +	rdev->bios = kmalloc(size, GFP_KERNEL);
> +	if (rdev->bios == NULL) {
> +		return false;
> +	}
> +	memcpy(rdev->bios, bios, size);
> +	return true;
> +}
> +#endif
> +
>  static bool radeon_read_bios(struct radeon_device *rdev)
>  {
>  	uint8_t __iomem *bios;
> @@ -490,6 +517,11 @@ bool radeon_get_bios(struct radeon_device *rdev)
>  	if (r == false) {
>  		r = radeon_read_disabled_bios(rdev);
>  	}
> +#ifdef CONFIG_CPU_LOONGSON3
> +	if (r == false) {
> +		r = loongson3_read_bios(rdev);
> +	}
> +#endif
>  	if (r == false || rdev->bios == NULL) {
>  		DRM_ERROR("Unable to locate a BIOS ROM\n");
>  		rdev->bios = NULL;
> diff --git a/drivers/gpu/drm/radeon/radeon_device.c b/drivers/gpu/drm/radeon/radeon_device.c
> index 066c98b..8aac7ab 100644
> --- a/drivers/gpu/drm/radeon/radeon_device.c
> +++ b/drivers/gpu/drm/radeon/radeon_device.c
> @@ -777,6 +777,11 @@ int radeon_device_init(struct radeon_device *rdev,
>  	    (rdev->family < CHIP_RS400))
>  		rdev->need_dma32 = true;
>  
> +#ifdef CONFIG_CPU_LOONGSON3
> +	/* Workaround: Loongson 3 doesn't support 40-bits DMA */
> +	rdev->need_dma32 = true;
> +#endif
> +
>  	dma_bits = rdev->need_dma32 ? 32 : 40;
>  	r = pci_set_dma_mask(rdev->pdev, DMA_BIT_MASK(dma_bits));
>  	if (r) {
> diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
> index c94a225..f49bdd1 100644
> --- a/drivers/gpu/drm/radeon/radeon_ttm.c
> +++ b/drivers/gpu/drm/radeon/radeon_ttm.c
> @@ -630,7 +630,7 @@ static int radeon_ttm_tt_populate(struct ttm_tt *ttm)
>  	}
>  #endif
>  
> -#ifdef CONFIG_SWIOTLB
> +#if defined(CONFIG_SWIOTLB) && !defined(CONFIG_CPU_LOONGSON3)
>  	if (swiotlb_nr_tbl()) {
>  		return ttm_dma_populate(&gtt->ttm, rdev->dev);
>  	}
> @@ -676,7 +676,7 @@ static void radeon_ttm_tt_unpopulate(struct ttm_tt *ttm)
>  	}
>  #endif
>  
> -#ifdef CONFIG_SWIOTLB
> +#if defined(CONFIG_SWIOTLB) && !defined(CONFIG_CPU_LOONGSON3)
>  	if (swiotlb_nr_tbl()) {
>  		ttm_dma_unpopulate(&gtt->ttm, rdev->dev);
>  		return;
> @@ -906,7 +906,7 @@ static int radeon_ttm_debugfs_init(struct radeon_device *rdev)
>  	radeon_mem_types_list[i].show = &ttm_page_alloc_debugfs;
>  	radeon_mem_types_list[i].driver_features = 0;
>  	radeon_mem_types_list[i++].data = NULL;
> -#ifdef CONFIG_SWIOTLB
> +#if defined(CONFIG_SWIOTLB) && !defined(CONFIG_CPU_LOONGSON3)
>  	if (swiotlb_nr_tbl()) {
>  		sprintf(radeon_mem_types_names[i], "ttm_dma_page_pool");
>  		radeon_mem_types_list[i].name = radeon_mem_types_names[i];
> diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
> index f8187ea..0df71ea 100644
> --- a/drivers/gpu/drm/ttm/ttm_bo_util.c
> +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
> @@ -472,7 +472,7 @@ pgprot_t ttm_io_prot(uint32_t caching_flags, pgprot_t tmp)
>  	else
>  		tmp = pgprot_noncached(tmp);
>  #endif
> -#if defined(__sparc__)
> +#if defined(__sparc__) || defined(__mips__)
>  	if (!(caching_flags & TTM_PL_FLAG_CACHED))
>  		tmp = pgprot_noncached(tmp);
>  #endif
> diff --git a/include/drm/drm_sarea.h b/include/drm/drm_sarea.h
> index ee5389d..1d1a858 100644
> --- a/include/drm/drm_sarea.h
> +++ b/include/drm/drm_sarea.h
> @@ -37,6 +37,8 @@
>  /* SAREA area needs to be at least a page */
>  #if defined(__alpha__)
>  #define SAREA_MAX                       0x2000U
> +#elif defined(__mips__)
> +#define SAREA_MAX                       0x4000U
>  #elif defined(__ia64__)
>  #define SAREA_MAX                       0x10000U	/* 64kB */
>  #else
> -- 
> 1.7.7.3
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel