* drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false
@ 2020-08-08 2:53 kernel test robot
2020-08-08 12:59 ` Vinod Koul
0 siblings, 1 reply; 4+ messages in thread
From: kernel test robot @ 2020-08-08 2:53 UTC (permalink / raw)
To: Ulf Hansson; +Cc: kbuild-all, linux-kernel, Vinod Koul
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 30185b69a2d533c4ba6ca926b8390ce7de495e29
commit: a39cddc9e3775100100a4272feed64faac831be9 dmaengine: pl330: Drop boilerplate code for suspend/resume
date: 8 months ago
compiler: aarch64-linux-gcc (GCC) 9.3.0
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
cppcheck warnings: (new ones prefixed by >>)
>> drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false [identicalConditionAfterEarlyExit]
return ret;
^
drivers/dma/pl330.c:2976:6: note: first condition
if (ret)
^
drivers/dma/pl330.c:2981:9: note: second condition
return ret;
^
>> drivers/dma/pl330.c:2798:23: warning: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used. [redundantAssignment]
desc->rqcfg.brst_len = get_burst_len(desc, len);
^
drivers/dma/pl330.c:2796:24: note: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used.
desc->rqcfg.brst_len = 1;
^
drivers/dma/pl330.c:2798:23: note: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used.
desc->rqcfg.brst_len = get_burst_len(desc, len);
^
vim +/ret +2981 drivers/dma/pl330.c
42bc9cf45939c2 Boojin Kim 2011-09-02 2753
b3040e40675ec2 Jassi Brar 2010-05-23 2754 static struct dma_async_tx_descriptor *
b3040e40675ec2 Jassi Brar 2010-05-23 2755 pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
b3040e40675ec2 Jassi Brar 2010-05-23 2756 dma_addr_t src, size_t len, unsigned long flags)
b3040e40675ec2 Jassi Brar 2010-05-23 2757 {
b3040e40675ec2 Jassi Brar 2010-05-23 2758 struct dma_pl330_desc *desc;
b3040e40675ec2 Jassi Brar 2010-05-23 2759 struct dma_pl330_chan *pch = to_pchan(chan);
f5636854f3fcee Maninder Singh 2015-05-26 2760 struct pl330_dmac *pl330;
b3040e40675ec2 Jassi Brar 2010-05-23 2761 int burst;
b3040e40675ec2 Jassi Brar 2010-05-23 2762
4e0e6109a1cc18 Rob Herring 2011-07-25 2763 if (unlikely(!pch || !len))
b3040e40675ec2 Jassi Brar 2010-05-23 2764 return NULL;
b3040e40675ec2 Jassi Brar 2010-05-23 2765
f5636854f3fcee Maninder Singh 2015-05-26 2766 pl330 = pch->dmac;
f5636854f3fcee Maninder Singh 2015-05-26 2767
b3040e40675ec2 Jassi Brar 2010-05-23 2768 desc = __pl330_prep_dma_memcpy(pch, dst, src, len);
b3040e40675ec2 Jassi Brar 2010-05-23 2769 if (!desc)
b3040e40675ec2 Jassi Brar 2010-05-23 2770 return NULL;
b3040e40675ec2 Jassi Brar 2010-05-23 2771
b3040e40675ec2 Jassi Brar 2010-05-23 2772 desc->rqcfg.src_inc = 1;
b3040e40675ec2 Jassi Brar 2010-05-23 2773 desc->rqcfg.dst_inc = 1;
9dc5a315fe515e Lars-Peter Clausen 2014-07-06 2774 desc->rqtype = DMA_MEM_TO_MEM;
b3040e40675ec2 Jassi Brar 2010-05-23 2775
b3040e40675ec2 Jassi Brar 2010-05-23 2776 /* Select max possible burst size */
f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2777 burst = pl330->pcfg.data_bus_width / 8;
b3040e40675ec2 Jassi Brar 2010-05-23 2778
137bd11090d89b Jon Medhurst 2014-11-07 2779 /*
137bd11090d89b Jon Medhurst 2014-11-07 2780 * Make sure we use a burst size that aligns with all the memcpy
137bd11090d89b Jon Medhurst 2014-11-07 2781 * parameters because our DMA programming algorithm doesn't cope with
137bd11090d89b Jon Medhurst 2014-11-07 2782 * transfers which straddle an entry in the DMA device's MFIFO.
137bd11090d89b Jon Medhurst 2014-11-07 2783 */
137bd11090d89b Jon Medhurst 2014-11-07 2784 while ((src | dst | len) & (burst - 1))
b3040e40675ec2 Jassi Brar 2010-05-23 2785 burst /= 2;
b3040e40675ec2 Jassi Brar 2010-05-23 2786
b3040e40675ec2 Jassi Brar 2010-05-23 2787 desc->rqcfg.brst_size = 0;
b3040e40675ec2 Jassi Brar 2010-05-23 2788 while (burst != (1 << desc->rqcfg.brst_size))
b3040e40675ec2 Jassi Brar 2010-05-23 2789 desc->rqcfg.brst_size++;
b3040e40675ec2 Jassi Brar 2010-05-23 2790
137bd11090d89b Jon Medhurst 2014-11-07 2791 /*
137bd11090d89b Jon Medhurst 2014-11-07 2792 * If burst size is smaller than bus width then make sure we only
137bd11090d89b Jon Medhurst 2014-11-07 2793 * transfer one at a time to avoid a burst stradling an MFIFO entry.
137bd11090d89b Jon Medhurst 2014-11-07 2794 */
137bd11090d89b Jon Medhurst 2014-11-07 2795 if (desc->rqcfg.brst_size * 8 < pl330->pcfg.data_bus_width)
137bd11090d89b Jon Medhurst 2014-11-07 2796 desc->rqcfg.brst_len = 1;
137bd11090d89b Jon Medhurst 2014-11-07 2797
b3040e40675ec2 Jassi Brar 2010-05-23 @2798 desc->rqcfg.brst_len = get_burst_len(desc, len);
ae128293d97404 Krzysztof Kozlowski 2015-06-15 2799 desc->bytes_requested = len;
b3040e40675ec2 Jassi Brar 2010-05-23 2800
b3040e40675ec2 Jassi Brar 2010-05-23 2801 desc->txd.flags = flags;
b3040e40675ec2 Jassi Brar 2010-05-23 2802
b3040e40675ec2 Jassi Brar 2010-05-23 2803 return &desc->txd;
b3040e40675ec2 Jassi Brar 2010-05-23 2804 }
b3040e40675ec2 Jassi Brar 2010-05-23 2805
f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2806 static void __pl330_giveback_desc(struct pl330_dmac *pl330,
52a9d179109c50 Chanho Park 2013-08-09 2807 struct dma_pl330_desc *first)
52a9d179109c50 Chanho Park 2013-08-09 2808 {
52a9d179109c50 Chanho Park 2013-08-09 2809 unsigned long flags;
52a9d179109c50 Chanho Park 2013-08-09 2810 struct dma_pl330_desc *desc;
52a9d179109c50 Chanho Park 2013-08-09 2811
52a9d179109c50 Chanho Park 2013-08-09 2812 if (!first)
52a9d179109c50 Chanho Park 2013-08-09 2813 return;
52a9d179109c50 Chanho Park 2013-08-09 2814
f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2815 spin_lock_irqsave(&pl330->pool_lock, flags);
52a9d179109c50 Chanho Park 2013-08-09 2816
52a9d179109c50 Chanho Park 2013-08-09 2817 while (!list_empty(&first->node)) {
52a9d179109c50 Chanho Park 2013-08-09 2818 desc = list_entry(first->node.next,
52a9d179109c50 Chanho Park 2013-08-09 2819 struct dma_pl330_desc, node);
f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2820 list_move_tail(&desc->node, &pl330->desc_pool);
52a9d179109c50 Chanho Park 2013-08-09 2821 }
52a9d179109c50 Chanho Park 2013-08-09 2822
f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2823 list_move_tail(&first->node, &pl330->desc_pool);
52a9d179109c50 Chanho Park 2013-08-09 2824
f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2825 spin_unlock_irqrestore(&pl330->pool_lock, flags);
52a9d179109c50 Chanho Park 2013-08-09 2826 }
52a9d179109c50 Chanho Park 2013-08-09 2827
b3040e40675ec2 Jassi Brar 2010-05-23 2828 static struct dma_async_tx_descriptor *
b3040e40675ec2 Jassi Brar 2010-05-23 2829 pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
db8196df4bb6f1 Vinod Koul 2011-10-13 2830 unsigned int sg_len, enum dma_transfer_direction direction,
185ecb5f4fd439 Alexandre Bounine 2012-03-08 2831 unsigned long flg, void *context)
b3040e40675ec2 Jassi Brar 2010-05-23 2832 {
b3040e40675ec2 Jassi Brar 2010-05-23 2833 struct dma_pl330_desc *first, *desc = NULL;
b3040e40675ec2 Jassi Brar 2010-05-23 2834 struct dma_pl330_chan *pch = to_pchan(chan);
b3040e40675ec2 Jassi Brar 2010-05-23 2835 struct scatterlist *sg;
1b9bb715e7c4c1 Boojin Kim 2011-09-02 2836 int i;
b3040e40675ec2 Jassi Brar 2010-05-23 2837
cd072515215ccc Thomas Abraham 2011-10-24 2838 if (unlikely(!pch || !sgl || !sg_len))
b3040e40675ec2 Jassi Brar 2010-05-23 2839 return NULL;
b3040e40675ec2 Jassi Brar 2010-05-23 2840
445897cbc9d3e2 Vinod Koul 2018-10-25 2841 pl330_config_write(chan, &pch->slave_config, direction);
445897cbc9d3e2 Vinod Koul 2018-10-25 2842
4d6d74e2209654 Robin Murphy 2017-05-19 2843 if (!pl330_prep_slave_fifo(pch, direction))
4d6d74e2209654 Robin Murphy 2017-05-19 2844 return NULL;
b3040e40675ec2 Jassi Brar 2010-05-23 2845
b3040e40675ec2 Jassi Brar 2010-05-23 2846 first = NULL;
b3040e40675ec2 Jassi Brar 2010-05-23 2847
b3040e40675ec2 Jassi Brar 2010-05-23 2848 for_each_sg(sgl, sg, sg_len, i) {
b3040e40675ec2 Jassi Brar 2010-05-23 2849
b3040e40675ec2 Jassi Brar 2010-05-23 2850 desc = pl330_get_desc(pch);
b3040e40675ec2 Jassi Brar 2010-05-23 2851 if (!desc) {
f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2852 struct pl330_dmac *pl330 = pch->dmac;
b3040e40675ec2 Jassi Brar 2010-05-23 2853
f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2854 dev_err(pch->dmac->ddma.dev,
b3040e40675ec2 Jassi Brar 2010-05-23 2855 "%s:%d Unable to fetch desc\n",
b3040e40675ec2 Jassi Brar 2010-05-23 2856 __func__, __LINE__);
f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2857 __pl330_giveback_desc(pl330, first);
b3040e40675ec2 Jassi Brar 2010-05-23 2858
b3040e40675ec2 Jassi Brar 2010-05-23 2859 return NULL;
b3040e40675ec2 Jassi Brar 2010-05-23 2860 }
b3040e40675ec2 Jassi Brar 2010-05-23 2861
b3040e40675ec2 Jassi Brar 2010-05-23 2862 if (!first)
b3040e40675ec2 Jassi Brar 2010-05-23 2863 first = desc;
b3040e40675ec2 Jassi Brar 2010-05-23 2864 else
b3040e40675ec2 Jassi Brar 2010-05-23 2865 list_add_tail(&desc->node, &first->node);
b3040e40675ec2 Jassi Brar 2010-05-23 2866
db8196df4bb6f1 Vinod Koul 2011-10-13 2867 if (direction == DMA_MEM_TO_DEV) {
b3040e40675ec2 Jassi Brar 2010-05-23 2868 desc->rqcfg.src_inc = 1;
b3040e40675ec2 Jassi Brar 2010-05-23 2869 desc->rqcfg.dst_inc = 0;
4d6d74e2209654 Robin Murphy 2017-05-19 2870 fill_px(&desc->px, pch->fifo_dma, sg_dma_address(sg),
4d6d74e2209654 Robin Murphy 2017-05-19 2871 sg_dma_len(sg));
b3040e40675ec2 Jassi Brar 2010-05-23 2872 } else {
b3040e40675ec2 Jassi Brar 2010-05-23 2873 desc->rqcfg.src_inc = 0;
b3040e40675ec2 Jassi Brar 2010-05-23 2874 desc->rqcfg.dst_inc = 1;
4d6d74e2209654 Robin Murphy 2017-05-19 2875 fill_px(&desc->px, sg_dma_address(sg), pch->fifo_dma,
4d6d74e2209654 Robin Murphy 2017-05-19 2876 sg_dma_len(sg));
b3040e40675ec2 Jassi Brar 2010-05-23 2877 }
b3040e40675ec2 Jassi Brar 2010-05-23 2878
1b9bb715e7c4c1 Boojin Kim 2011-09-02 2879 desc->rqcfg.brst_size = pch->burst_sz;
1d48745b192a7a Frank Mori Hess 2018-04-18 2880 desc->rqcfg.brst_len = pch->burst_len;
9dc5a315fe515e Lars-Peter Clausen 2014-07-06 2881 desc->rqtype = direction;
aee4d1fac88725 Robert Baldyga 2015-02-11 2882 desc->bytes_requested = sg_dma_len(sg);
b3040e40675ec2 Jassi Brar 2010-05-23 2883 }
b3040e40675ec2 Jassi Brar 2010-05-23 2884
b3040e40675ec2 Jassi Brar 2010-05-23 2885 /* Return the last desc in the chain */
b3040e40675ec2 Jassi Brar 2010-05-23 2886 desc->txd.flags = flg;
b3040e40675ec2 Jassi Brar 2010-05-23 2887 return &desc->txd;
b3040e40675ec2 Jassi Brar 2010-05-23 2888 }
b3040e40675ec2 Jassi Brar 2010-05-23 2889
b3040e40675ec2 Jassi Brar 2010-05-23 2890 static irqreturn_t pl330_irq_handler(int irq, void *data)
b3040e40675ec2 Jassi Brar 2010-05-23 2891 {
b3040e40675ec2 Jassi Brar 2010-05-23 2892 if (pl330_update(data))
b3040e40675ec2 Jassi Brar 2010-05-23 2893 return IRQ_HANDLED;
b3040e40675ec2 Jassi Brar 2010-05-23 2894 else
b3040e40675ec2 Jassi Brar 2010-05-23 2895 return IRQ_NONE;
b3040e40675ec2 Jassi Brar 2010-05-23 2896 }
b3040e40675ec2 Jassi Brar 2010-05-23 2897
ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2898 #define PL330_DMA_BUSWIDTHS \
ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2899 BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2900 BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2901 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2902 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2903 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)
ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2904
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2905 #ifdef CONFIG_DEBUG_FS
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2906 static int pl330_debugfs_show(struct seq_file *s, void *data)
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2907 {
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2908 struct pl330_dmac *pl330 = s->private;
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2909 int chans, pchs, ch, pr;
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2910
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2911 chans = pl330->pcfg.num_chan;
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2912 pchs = pl330->num_peripherals;
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2913
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2914 seq_puts(s, "PL330 physical channels:\n");
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2915 seq_puts(s, "THREAD:\t\tCHANNEL:\n");
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2916 seq_puts(s, "--------\t-----\n");
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2917 for (ch = 0; ch < chans; ch++) {
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2918 struct pl330_thread *thrd = &pl330->channels[ch];
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2919 int found = -1;
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2920
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2921 for (pr = 0; pr < pchs; pr++) {
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2922 struct dma_pl330_chan *pch = &pl330->peripherals[pr];
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2923
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2924 if (!pch->thread || thrd->id != pch->thread->id)
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2925 continue;
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2926
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2927 found = pr;
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2928 }
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2929
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2930 seq_printf(s, "%d\t\t", thrd->id);
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2931 if (found == -1)
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2932 seq_puts(s, "--\n");
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2933 else
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2934 seq_printf(s, "%d\n", found);
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2935 }
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2936
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2937 return 0;
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2938 }
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2939
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2940 DEFINE_SHOW_ATTRIBUTE(pl330_debugfs);
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2941
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2942 static inline void init_pl330_debugfs(struct pl330_dmac *pl330)
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2943 {
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2944 debugfs_create_file(dev_name(pl330->ddma.dev),
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2945 S_IFREG | 0444, NULL, pl330,
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2946 &pl330_debugfs_fops);
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2947 }
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2948 #else
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2949 static inline void init_pl330_debugfs(struct pl330_dmac *pl330)
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2950 {
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2951 }
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2952 #endif
b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2953
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2954 /*
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2955 * Runtime PM callbacks are provided by amba/bus.c driver.
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2956 *
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2957 * It is assumed here that IRQ safe runtime PM is chosen in probe and amba
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2958 * bus driver will only disable/enable the clock in runtime PM callbacks.
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2959 */
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2960 static int __maybe_unused pl330_suspend(struct device *dev)
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2961 {
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2962 struct amba_device *pcdev = to_amba_device(dev);
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2963
a39cddc9e37751 Ulf Hansson 2019-12-05 2964 pm_runtime_force_suspend(dev);
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2965 amba_pclk_unprepare(pcdev);
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2966
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2967 return 0;
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2968 }
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2969
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2970 static int __maybe_unused pl330_resume(struct device *dev)
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2971 {
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2972 struct amba_device *pcdev = to_amba_device(dev);
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2973 int ret;
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2974
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2975 ret = amba_pclk_prepare(pcdev);
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2976 if (ret)
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2977 return ret;
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2978
a39cddc9e37751 Ulf Hansson 2019-12-05 2979 pm_runtime_force_resume(dev);
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2980
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 @2981 return ret;
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2982 }
b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2983
:::::: The code at line 2981 was first introduced by commit
:::::: b816ccc5c01fb7fe1fb001ff7aa5aa7e5a8aa76b ARM: 8206/1: dmaengine: pl330: Add PM sleep support
:::::: TO: Krzysztof Kozlowski <k.kozlowski@samsung.com>
:::::: CC: Russell King <rmk+kernel@arm.linux.org.uk>
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false
2020-08-08 2:53 drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false kernel test robot
@ 2020-08-08 12:59 ` Vinod Koul
2020-08-24 13:50 ` Marek Szyprowski
0 siblings, 1 reply; 4+ messages in thread
From: Vinod Koul @ 2020-08-08 12:59 UTC (permalink / raw)
To: kernel test robot, Sugar Zhang, Marek Szyprowski
Cc: Ulf Hansson, kbuild-all, linux-kernel
On 08-08-20, 10:53, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 30185b69a2d533c4ba6ca926b8390ce7de495e29
> commit: a39cddc9e3775100100a4272feed64faac831be9 dmaengine: pl330: Drop boilerplate code for suspend/resume
> date: 8 months ago
> compiler: aarch64-linux-gcc (GCC) 9.3.0
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
>
>
> cppcheck warnings: (new ones prefixed by >>)
>
> >> drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false [identicalConditionAfterEarlyExit]
> return ret;
> ^
> drivers/dma/pl330.c:2976:6: note: first condition
> if (ret)
> ^
> drivers/dma/pl330.c:2981:9: note: second condition
> return ret;
This one could be fixed by making this as return 0, but is harmless
> ^
> >> drivers/dma/pl330.c:2798:23: warning: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used. [redundantAssignment]
> desc->rqcfg.brst_len = get_burst_len(desc, len);
> ^
> drivers/dma/pl330.c:2796:24: note: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used.
> desc->rqcfg.brst_len = 1;
> ^
> drivers/dma/pl330.c:2798:23: note: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used.
> desc->rqcfg.brst_len = get_burst_len(desc, len);
This one actually seems like a bug. Reading the code I think
get_burst_len() should be called first before checking if burst size is
smaller and setting to 1 in that case
Sugar Zhang, Marek Szyprowski can you folks check this?
> ^
>
> vim +/ret +2981 drivers/dma/pl330.c
>
> 42bc9cf45939c2 Boojin Kim 2011-09-02 2753
> b3040e40675ec2 Jassi Brar 2010-05-23 2754 static struct dma_async_tx_descriptor *
> b3040e40675ec2 Jassi Brar 2010-05-23 2755 pl330_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dst,
> b3040e40675ec2 Jassi Brar 2010-05-23 2756 dma_addr_t src, size_t len, unsigned long flags)
> b3040e40675ec2 Jassi Brar 2010-05-23 2757 {
> b3040e40675ec2 Jassi Brar 2010-05-23 2758 struct dma_pl330_desc *desc;
> b3040e40675ec2 Jassi Brar 2010-05-23 2759 struct dma_pl330_chan *pch = to_pchan(chan);
> f5636854f3fcee Maninder Singh 2015-05-26 2760 struct pl330_dmac *pl330;
> b3040e40675ec2 Jassi Brar 2010-05-23 2761 int burst;
> b3040e40675ec2 Jassi Brar 2010-05-23 2762
> 4e0e6109a1cc18 Rob Herring 2011-07-25 2763 if (unlikely(!pch || !len))
> b3040e40675ec2 Jassi Brar 2010-05-23 2764 return NULL;
> b3040e40675ec2 Jassi Brar 2010-05-23 2765
> f5636854f3fcee Maninder Singh 2015-05-26 2766 pl330 = pch->dmac;
> f5636854f3fcee Maninder Singh 2015-05-26 2767
> b3040e40675ec2 Jassi Brar 2010-05-23 2768 desc = __pl330_prep_dma_memcpy(pch, dst, src, len);
> b3040e40675ec2 Jassi Brar 2010-05-23 2769 if (!desc)
> b3040e40675ec2 Jassi Brar 2010-05-23 2770 return NULL;
> b3040e40675ec2 Jassi Brar 2010-05-23 2771
> b3040e40675ec2 Jassi Brar 2010-05-23 2772 desc->rqcfg.src_inc = 1;
> b3040e40675ec2 Jassi Brar 2010-05-23 2773 desc->rqcfg.dst_inc = 1;
> 9dc5a315fe515e Lars-Peter Clausen 2014-07-06 2774 desc->rqtype = DMA_MEM_TO_MEM;
> b3040e40675ec2 Jassi Brar 2010-05-23 2775
> b3040e40675ec2 Jassi Brar 2010-05-23 2776 /* Select max possible burst size */
> f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2777 burst = pl330->pcfg.data_bus_width / 8;
> b3040e40675ec2 Jassi Brar 2010-05-23 2778
> 137bd11090d89b Jon Medhurst 2014-11-07 2779 /*
> 137bd11090d89b Jon Medhurst 2014-11-07 2780 * Make sure we use a burst size that aligns with all the memcpy
> 137bd11090d89b Jon Medhurst 2014-11-07 2781 * parameters because our DMA programming algorithm doesn't cope with
> 137bd11090d89b Jon Medhurst 2014-11-07 2782 * transfers which straddle an entry in the DMA device's MFIFO.
> 137bd11090d89b Jon Medhurst 2014-11-07 2783 */
> 137bd11090d89b Jon Medhurst 2014-11-07 2784 while ((src | dst | len) & (burst - 1))
> b3040e40675ec2 Jassi Brar 2010-05-23 2785 burst /= 2;
> b3040e40675ec2 Jassi Brar 2010-05-23 2786
> b3040e40675ec2 Jassi Brar 2010-05-23 2787 desc->rqcfg.brst_size = 0;
> b3040e40675ec2 Jassi Brar 2010-05-23 2788 while (burst != (1 << desc->rqcfg.brst_size))
> b3040e40675ec2 Jassi Brar 2010-05-23 2789 desc->rqcfg.brst_size++;
> b3040e40675ec2 Jassi Brar 2010-05-23 2790
> 137bd11090d89b Jon Medhurst 2014-11-07 2791 /*
> 137bd11090d89b Jon Medhurst 2014-11-07 2792 * If burst size is smaller than bus width then make sure we only
> 137bd11090d89b Jon Medhurst 2014-11-07 2793 * transfer one at a time to avoid a burst stradling an MFIFO entry.
> 137bd11090d89b Jon Medhurst 2014-11-07 2794 */
> 137bd11090d89b Jon Medhurst 2014-11-07 2795 if (desc->rqcfg.brst_size * 8 < pl330->pcfg.data_bus_width)
> 137bd11090d89b Jon Medhurst 2014-11-07 2796 desc->rqcfg.brst_len = 1;
> 137bd11090d89b Jon Medhurst 2014-11-07 2797
> b3040e40675ec2 Jassi Brar 2010-05-23 @2798 desc->rqcfg.brst_len = get_burst_len(desc, len);
> ae128293d97404 Krzysztof Kozlowski 2015-06-15 2799 desc->bytes_requested = len;
> b3040e40675ec2 Jassi Brar 2010-05-23 2800
> b3040e40675ec2 Jassi Brar 2010-05-23 2801 desc->txd.flags = flags;
> b3040e40675ec2 Jassi Brar 2010-05-23 2802
> b3040e40675ec2 Jassi Brar 2010-05-23 2803 return &desc->txd;
> b3040e40675ec2 Jassi Brar 2010-05-23 2804 }
> b3040e40675ec2 Jassi Brar 2010-05-23 2805
> f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2806 static void __pl330_giveback_desc(struct pl330_dmac *pl330,
> 52a9d179109c50 Chanho Park 2013-08-09 2807 struct dma_pl330_desc *first)
> 52a9d179109c50 Chanho Park 2013-08-09 2808 {
> 52a9d179109c50 Chanho Park 2013-08-09 2809 unsigned long flags;
> 52a9d179109c50 Chanho Park 2013-08-09 2810 struct dma_pl330_desc *desc;
> 52a9d179109c50 Chanho Park 2013-08-09 2811
> 52a9d179109c50 Chanho Park 2013-08-09 2812 if (!first)
> 52a9d179109c50 Chanho Park 2013-08-09 2813 return;
> 52a9d179109c50 Chanho Park 2013-08-09 2814
> f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2815 spin_lock_irqsave(&pl330->pool_lock, flags);
> 52a9d179109c50 Chanho Park 2013-08-09 2816
> 52a9d179109c50 Chanho Park 2013-08-09 2817 while (!list_empty(&first->node)) {
> 52a9d179109c50 Chanho Park 2013-08-09 2818 desc = list_entry(first->node.next,
> 52a9d179109c50 Chanho Park 2013-08-09 2819 struct dma_pl330_desc, node);
> f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2820 list_move_tail(&desc->node, &pl330->desc_pool);
> 52a9d179109c50 Chanho Park 2013-08-09 2821 }
> 52a9d179109c50 Chanho Park 2013-08-09 2822
> f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2823 list_move_tail(&first->node, &pl330->desc_pool);
> 52a9d179109c50 Chanho Park 2013-08-09 2824
> f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2825 spin_unlock_irqrestore(&pl330->pool_lock, flags);
> 52a9d179109c50 Chanho Park 2013-08-09 2826 }
> 52a9d179109c50 Chanho Park 2013-08-09 2827
> b3040e40675ec2 Jassi Brar 2010-05-23 2828 static struct dma_async_tx_descriptor *
> b3040e40675ec2 Jassi Brar 2010-05-23 2829 pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
> db8196df4bb6f1 Vinod Koul 2011-10-13 2830 unsigned int sg_len, enum dma_transfer_direction direction,
> 185ecb5f4fd439 Alexandre Bounine 2012-03-08 2831 unsigned long flg, void *context)
> b3040e40675ec2 Jassi Brar 2010-05-23 2832 {
> b3040e40675ec2 Jassi Brar 2010-05-23 2833 struct dma_pl330_desc *first, *desc = NULL;
> b3040e40675ec2 Jassi Brar 2010-05-23 2834 struct dma_pl330_chan *pch = to_pchan(chan);
> b3040e40675ec2 Jassi Brar 2010-05-23 2835 struct scatterlist *sg;
> 1b9bb715e7c4c1 Boojin Kim 2011-09-02 2836 int i;
> b3040e40675ec2 Jassi Brar 2010-05-23 2837
> cd072515215ccc Thomas Abraham 2011-10-24 2838 if (unlikely(!pch || !sgl || !sg_len))
> b3040e40675ec2 Jassi Brar 2010-05-23 2839 return NULL;
> b3040e40675ec2 Jassi Brar 2010-05-23 2840
> 445897cbc9d3e2 Vinod Koul 2018-10-25 2841 pl330_config_write(chan, &pch->slave_config, direction);
> 445897cbc9d3e2 Vinod Koul 2018-10-25 2842
> 4d6d74e2209654 Robin Murphy 2017-05-19 2843 if (!pl330_prep_slave_fifo(pch, direction))
> 4d6d74e2209654 Robin Murphy 2017-05-19 2844 return NULL;
> b3040e40675ec2 Jassi Brar 2010-05-23 2845
> b3040e40675ec2 Jassi Brar 2010-05-23 2846 first = NULL;
> b3040e40675ec2 Jassi Brar 2010-05-23 2847
> b3040e40675ec2 Jassi Brar 2010-05-23 2848 for_each_sg(sgl, sg, sg_len, i) {
> b3040e40675ec2 Jassi Brar 2010-05-23 2849
> b3040e40675ec2 Jassi Brar 2010-05-23 2850 desc = pl330_get_desc(pch);
> b3040e40675ec2 Jassi Brar 2010-05-23 2851 if (!desc) {
> f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2852 struct pl330_dmac *pl330 = pch->dmac;
> b3040e40675ec2 Jassi Brar 2010-05-23 2853
> f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2854 dev_err(pch->dmac->ddma.dev,
> b3040e40675ec2 Jassi Brar 2010-05-23 2855 "%s:%d Unable to fetch desc\n",
> b3040e40675ec2 Jassi Brar 2010-05-23 2856 __func__, __LINE__);
> f6f2421c0a1cb6 Lars-Peter Clausen 2014-07-06 2857 __pl330_giveback_desc(pl330, first);
> b3040e40675ec2 Jassi Brar 2010-05-23 2858
> b3040e40675ec2 Jassi Brar 2010-05-23 2859 return NULL;
> b3040e40675ec2 Jassi Brar 2010-05-23 2860 }
> b3040e40675ec2 Jassi Brar 2010-05-23 2861
> b3040e40675ec2 Jassi Brar 2010-05-23 2862 if (!first)
> b3040e40675ec2 Jassi Brar 2010-05-23 2863 first = desc;
> b3040e40675ec2 Jassi Brar 2010-05-23 2864 else
> b3040e40675ec2 Jassi Brar 2010-05-23 2865 list_add_tail(&desc->node, &first->node);
> b3040e40675ec2 Jassi Brar 2010-05-23 2866
> db8196df4bb6f1 Vinod Koul 2011-10-13 2867 if (direction == DMA_MEM_TO_DEV) {
> b3040e40675ec2 Jassi Brar 2010-05-23 2868 desc->rqcfg.src_inc = 1;
> b3040e40675ec2 Jassi Brar 2010-05-23 2869 desc->rqcfg.dst_inc = 0;
> 4d6d74e2209654 Robin Murphy 2017-05-19 2870 fill_px(&desc->px, pch->fifo_dma, sg_dma_address(sg),
> 4d6d74e2209654 Robin Murphy 2017-05-19 2871 sg_dma_len(sg));
> b3040e40675ec2 Jassi Brar 2010-05-23 2872 } else {
> b3040e40675ec2 Jassi Brar 2010-05-23 2873 desc->rqcfg.src_inc = 0;
> b3040e40675ec2 Jassi Brar 2010-05-23 2874 desc->rqcfg.dst_inc = 1;
> 4d6d74e2209654 Robin Murphy 2017-05-19 2875 fill_px(&desc->px, sg_dma_address(sg), pch->fifo_dma,
> 4d6d74e2209654 Robin Murphy 2017-05-19 2876 sg_dma_len(sg));
> b3040e40675ec2 Jassi Brar 2010-05-23 2877 }
> b3040e40675ec2 Jassi Brar 2010-05-23 2878
> 1b9bb715e7c4c1 Boojin Kim 2011-09-02 2879 desc->rqcfg.brst_size = pch->burst_sz;
> 1d48745b192a7a Frank Mori Hess 2018-04-18 2880 desc->rqcfg.brst_len = pch->burst_len;
> 9dc5a315fe515e Lars-Peter Clausen 2014-07-06 2881 desc->rqtype = direction;
> aee4d1fac88725 Robert Baldyga 2015-02-11 2882 desc->bytes_requested = sg_dma_len(sg);
> b3040e40675ec2 Jassi Brar 2010-05-23 2883 }
> b3040e40675ec2 Jassi Brar 2010-05-23 2884
> b3040e40675ec2 Jassi Brar 2010-05-23 2885 /* Return the last desc in the chain */
> b3040e40675ec2 Jassi Brar 2010-05-23 2886 desc->txd.flags = flg;
> b3040e40675ec2 Jassi Brar 2010-05-23 2887 return &desc->txd;
> b3040e40675ec2 Jassi Brar 2010-05-23 2888 }
> b3040e40675ec2 Jassi Brar 2010-05-23 2889
> b3040e40675ec2 Jassi Brar 2010-05-23 2890 static irqreturn_t pl330_irq_handler(int irq, void *data)
> b3040e40675ec2 Jassi Brar 2010-05-23 2891 {
> b3040e40675ec2 Jassi Brar 2010-05-23 2892 if (pl330_update(data))
> b3040e40675ec2 Jassi Brar 2010-05-23 2893 return IRQ_HANDLED;
> b3040e40675ec2 Jassi Brar 2010-05-23 2894 else
> b3040e40675ec2 Jassi Brar 2010-05-23 2895 return IRQ_NONE;
> b3040e40675ec2 Jassi Brar 2010-05-23 2896 }
> b3040e40675ec2 Jassi Brar 2010-05-23 2897
> ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2898 #define PL330_DMA_BUSWIDTHS \
> ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2899 BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
> ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2900 BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
> ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2901 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
> ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2902 BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
> ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2903 BIT(DMA_SLAVE_BUSWIDTH_8_BYTES)
> ca38ff133eb85b Lars-Peter Clausen 2013-07-15 2904
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2905 #ifdef CONFIG_DEBUG_FS
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2906 static int pl330_debugfs_show(struct seq_file *s, void *data)
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2907 {
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2908 struct pl330_dmac *pl330 = s->private;
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2909 int chans, pchs, ch, pr;
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2910
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2911 chans = pl330->pcfg.num_chan;
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2912 pchs = pl330->num_peripherals;
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2913
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2914 seq_puts(s, "PL330 physical channels:\n");
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2915 seq_puts(s, "THREAD:\t\tCHANNEL:\n");
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2916 seq_puts(s, "--------\t-----\n");
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2917 for (ch = 0; ch < chans; ch++) {
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2918 struct pl330_thread *thrd = &pl330->channels[ch];
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2919 int found = -1;
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2920
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2921 for (pr = 0; pr < pchs; pr++) {
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2922 struct dma_pl330_chan *pch = &pl330->peripherals[pr];
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2923
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2924 if (!pch->thread || thrd->id != pch->thread->id)
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2925 continue;
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2926
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2927 found = pr;
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2928 }
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2929
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2930 seq_printf(s, "%d\t\t", thrd->id);
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2931 if (found == -1)
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2932 seq_puts(s, "--\n");
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2933 else
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2934 seq_printf(s, "%d\n", found);
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2935 }
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2936
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2937 return 0;
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2938 }
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2939
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2940 DEFINE_SHOW_ATTRIBUTE(pl330_debugfs);
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2941
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2942 static inline void init_pl330_debugfs(struct pl330_dmac *pl330)
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2943 {
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2944 debugfs_create_file(dev_name(pl330->ddma.dev),
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2945 S_IFREG | 0444, NULL, pl330,
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2946 &pl330_debugfs_fops);
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2947 }
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2948 #else
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2949 static inline void init_pl330_debugfs(struct pl330_dmac *pl330)
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2950 {
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2951 }
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2952 #endif
> b45aef3aef6361 Katsuhiro Suzuki 2019-03-17 2953
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2954 /*
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2955 * Runtime PM callbacks are provided by amba/bus.c driver.
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2956 *
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2957 * It is assumed here that IRQ safe runtime PM is chosen in probe and amba
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2958 * bus driver will only disable/enable the clock in runtime PM callbacks.
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2959 */
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2960 static int __maybe_unused pl330_suspend(struct device *dev)
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2961 {
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2962 struct amba_device *pcdev = to_amba_device(dev);
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2963
> a39cddc9e37751 Ulf Hansson 2019-12-05 2964 pm_runtime_force_suspend(dev);
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2965 amba_pclk_unprepare(pcdev);
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2966
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2967 return 0;
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2968 }
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2969
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2970 static int __maybe_unused pl330_resume(struct device *dev)
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2971 {
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2972 struct amba_device *pcdev = to_amba_device(dev);
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2973 int ret;
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2974
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2975 ret = amba_pclk_prepare(pcdev);
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2976 if (ret)
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2977 return ret;
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2978
> a39cddc9e37751 Ulf Hansson 2019-12-05 2979 pm_runtime_force_resume(dev);
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2980
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 @2981 return ret;
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2982 }
> b816ccc5c01fb7 Krzysztof Kozlowski 2014-11-18 2983
>
> :::::: The code at line 2981 was first introduced by commit
> :::::: b816ccc5c01fb7fe1fb001ff7aa5aa7e5a8aa76b ARM: 8206/1: dmaengine: pl330: Add PM sleep support
>
> :::::: TO: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> :::::: CC: Russell King <rmk+kernel@arm.linux.org.uk>
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
--
~Vinod
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false
2020-08-08 12:59 ` Vinod Koul
@ 2020-08-24 13:50 ` Marek Szyprowski
2020-08-24 13:54 ` Vinod Koul
0 siblings, 1 reply; 4+ messages in thread
From: Marek Szyprowski @ 2020-08-24 13:50 UTC (permalink / raw)
To: Vinod Koul, kernel test robot, Sugar Zhang
Cc: Ulf Hansson, kbuild-all, linux-kernel
Hi Vinod,
On 08.08.2020 14:59, Vinod Koul wrote:
> On 08-08-20, 10:53, kernel test robot wrote:
>> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
>> head: 30185b69a2d533c4ba6ca926b8390ce7de495e29
>> commit: a39cddc9e3775100100a4272feed64faac831be9 dmaengine: pl330: Drop boilerplate code for suspend/resume
>> date: 8 months ago
>> compiler: aarch64-linux-gcc (GCC) 9.3.0
>>
>> If you fix the issue, kindly add following tag as appropriate
>> Reported-by: kernel test robot <lkp@intel.com>
>>
>>
>> cppcheck warnings: (new ones prefixed by >>)
>>
>>>> drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false [identicalConditionAfterEarlyExit]
>> return ret;
>> ^
>> drivers/dma/pl330.c:2976:6: note: first condition
>> if (ret)
>> ^
>> drivers/dma/pl330.c:2981:9: note: second condition
>> return ret;
> This one could be fixed by making this as return 0, but is harmless
Right, with CONFIG_PM disabled, pm_runtime_force_resume() is noop, what
causes the above warning.
>> ^
>>>> drivers/dma/pl330.c:2798:23: warning: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used. [redundantAssignment]
>> desc->rqcfg.brst_len = get_burst_len(desc, len);
>> ^
>> drivers/dma/pl330.c:2796:24: note: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used.
>> desc->rqcfg.brst_len = 1;
>> ^
>> drivers/dma/pl330.c:2798:23: note: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used.
>> desc->rqcfg.brst_len = get_burst_len(desc, len);
> This one actually seems like a bug. Reading the code I think
> get_burst_len() should be called first before checking if burst size is
> smaller and setting to 1 in that case
>
> Sugar Zhang, Marek Szyprowski can you folks check this?
Indeed. It look that the commit 137bd11090d89b added
desc->rqcfg.brst_len = 1 assignment before the desc->rqcfg.brst_len is
set. Maybe this was a result of the broken rebase or so. No idea. It
makes sense to switch the order and call desc->rqcfg.brst_len =
get_burst_len(desc, len) first. I can send a patch if you want.
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false
2020-08-24 13:50 ` Marek Szyprowski
@ 2020-08-24 13:54 ` Vinod Koul
0 siblings, 0 replies; 4+ messages in thread
From: Vinod Koul @ 2020-08-24 13:54 UTC (permalink / raw)
To: Marek Szyprowski
Cc: kernel test robot, Sugar Zhang, Ulf Hansson, kbuild-all, linux-kernel
On 24-08-20, 15:50, Marek Szyprowski wrote:
> Hi Vinod,
>
> On 08.08.2020 14:59, Vinod Koul wrote:
> > On 08-08-20, 10:53, kernel test robot wrote:
> >> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> >> head: 30185b69a2d533c4ba6ca926b8390ce7de495e29
> >> commit: a39cddc9e3775100100a4272feed64faac831be9 dmaengine: pl330: Drop boilerplate code for suspend/resume
> >> date: 8 months ago
> >> compiler: aarch64-linux-gcc (GCC) 9.3.0
> >>
> >> If you fix the issue, kindly add following tag as appropriate
> >> Reported-by: kernel test robot <lkp@intel.com>
> >>
> >>
> >> cppcheck warnings: (new ones prefixed by >>)
> >>
> >>>> drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false [identicalConditionAfterEarlyExit]
> >> return ret;
> >> ^
> >> drivers/dma/pl330.c:2976:6: note: first condition
> >> if (ret)
> >> ^
> >> drivers/dma/pl330.c:2981:9: note: second condition
> >> return ret;
> > This one could be fixed by making this as return 0, but is harmless
>
> Right, with CONFIG_PM disabled, pm_runtime_force_resume() is noop, what
> causes the above warning.
>
> >> ^
> >>>> drivers/dma/pl330.c:2798:23: warning: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used. [redundantAssignment]
> >> desc->rqcfg.brst_len = get_burst_len(desc, len);
> >> ^
> >> drivers/dma/pl330.c:2796:24: note: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used.
> >> desc->rqcfg.brst_len = 1;
> >> ^
> >> drivers/dma/pl330.c:2798:23: note: Variable 'desc->rqcfg.brst_len' is reassigned a value before the old one has been used.
> >> desc->rqcfg.brst_len = get_burst_len(desc, len);
> > This one actually seems like a bug. Reading the code I think
> > get_burst_len() should be called first before checking if burst size is
> > smaller and setting to 1 in that case
> >
> > Sugar Zhang, Marek Szyprowski can you folks check this?
>
> Indeed. It look that the commit 137bd11090d89b added
> desc->rqcfg.brst_len = 1 assignment before the desc->rqcfg.brst_len is
> set. Maybe this was a result of the broken rebase or so. No idea. It
> makes sense to switch the order and call desc->rqcfg.brst_len =
> get_burst_len(desc, len) first. I can send a patch if you want.
That would be great Marek
Thanks
--
~Vinod
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-08-24 13:54 UTC | newest]
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2020-08-08 2:53 drivers/dma/pl330.c:2981:9: warning: Identical condition 'ret', second condition is always false kernel test robot
2020-08-08 12:59 ` Vinod Koul
2020-08-24 13:50 ` Marek Szyprowski
2020-08-24 13:54 ` Vinod Koul
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