drivers/i3c/master/dw-i3c-master.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
Bus-speed could be default(12.5MHz) or defined by users in dts.
Dw-i3c-master should not hard-code the initial speed to be
I3C_BUS_TYP_I3C_SCL_RATE (12.5MHz)
And because of Synopsys's I3C controller limit (hcnt/lcnt register
length) and core-clk provided, there is a limit to bus speed, too.
For example, when core-clk is 250 MHz, the bus speed cannot be
lowered below 1MHz.
Tested: tested with an i3c sensor and captured with a logic analyzer.
Signed-off-by: Jack Chen <zenghuchen@google.com>
---
drivers/i3c/master/dw-i3c-master.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index 51a8608203de..13309dde1518 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -531,7 +531,7 @@ static int dw_i3c_clk_cfg(struct dw_i3c_master *master)
if (hcnt < SCL_I3C_TIMING_CNT_MIN)
hcnt = SCL_I3C_TIMING_CNT_MIN;
- lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_TYP_I3C_SCL_RATE) - hcnt;
+ lcnt = DIV_ROUND_UP(core_rate, master->base.bus.scl_rate.i3c) - hcnt;
if (lcnt < SCL_I3C_TIMING_CNT_MIN)
lcnt = SCL_I3C_TIMING_CNT_MIN;
@@ -541,7 +541,7 @@ static int dw_i3c_clk_cfg(struct dw_i3c_master *master)
if (!(readl(master->regs + DEVICE_CTRL) & DEV_CTRL_I2C_SLAVE_PRESENT))
writel(BUS_I3C_MST_FREE(lcnt), master->regs + BUS_FREE_TIMING);
- lcnt = DIV_ROUND_UP(I3C_BUS_TLOW_OD_MIN_NS, core_period);
+ lcnt = max(DIV_ROUND_UP(I3C_BUS_TLOW_OD_MIN_NS, core_period), lcnt);
scl_timing = SCL_I3C_TIMING_HCNT(hcnt) | SCL_I3C_TIMING_LCNT(lcnt);
writel(scl_timing, master->regs + SCL_I3C_OD_TIMING);
--
2.39.1.581.gbfd45094c4-goog
Hi Jack, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v6.2-rc8 next-20230213] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Jack-Chen/i3c-update-dw-i3c-master-i3c_clk_cfg-function/20230213-222533 patch link: https://lore.kernel.org/r/20230213142336.192875-1-zenghuchen%40google.com patch subject: [PATCH] i3c: update dw-i3c-master i3c_clk_cfg function config: i386-randconfig-s001 (https://download.01.org/0day-ci/archive/20230214/202302141029.2CS1z9de-lkp@intel.com/config) compiler: gcc-11 (Debian 11.3.0-8) 11.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.4-39-gce1a6720-dirty # https://github.com/intel-lab-lkp/linux/commit/e85b41ae5bb17077ac7d01bdd13c48ea1f83ea42 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Jack-Chen/i3c-update-dw-i3c-master-i3c_clk_cfg-function/20230213-222533 git checkout e85b41ae5bb17077ac7d01bdd13c48ea1f83ea42 # save the config file mkdir build_dir && cp config build_dir/.config make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 olddefconfig make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 SHELL=/bin/bash drivers/i3c/master/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@intel.com> | Link: https://lore.kernel.org/oe-kbuild-all/202302141029.2CS1z9de-lkp@intel.com/ sparse warnings: (new ones prefixed by >>) >> drivers/i3c/master/dw-i3c-master.c:544:16: sparse: sparse: incompatible types in comparison expression (different type sizes): >> drivers/i3c/master/dw-i3c-master.c:544:16: sparse: unsigned long * >> drivers/i3c/master/dw-i3c-master.c:544:16: sparse: unsigned char * vim +544 drivers/i3c/master/dw-i3c-master.c 517 518 static int dw_i3c_clk_cfg(struct dw_i3c_master *master) 519 { 520 unsigned long core_rate, core_period; 521 u32 scl_timing; 522 u8 hcnt, lcnt; 523 524 core_rate = clk_get_rate(master->core_clk); 525 if (!core_rate) 526 return -EINVAL; 527 528 core_period = DIV_ROUND_UP(1000000000, core_rate); 529 530 hcnt = DIV_ROUND_UP(I3C_BUS_THIGH_MAX_NS, core_period) - 1; 531 if (hcnt < SCL_I3C_TIMING_CNT_MIN) 532 hcnt = SCL_I3C_TIMING_CNT_MIN; 533 534 lcnt = DIV_ROUND_UP(core_rate, master->base.bus.scl_rate.i3c) - hcnt; 535 if (lcnt < SCL_I3C_TIMING_CNT_MIN) 536 lcnt = SCL_I3C_TIMING_CNT_MIN; 537 538 scl_timing = SCL_I3C_TIMING_HCNT(hcnt) | SCL_I3C_TIMING_LCNT(lcnt); 539 writel(scl_timing, master->regs + SCL_I3C_PP_TIMING); 540 541 if (!(readl(master->regs + DEVICE_CTRL) & DEV_CTRL_I2C_SLAVE_PRESENT)) 542 writel(BUS_I3C_MST_FREE(lcnt), master->regs + BUS_FREE_TIMING); 543 > 544 lcnt = max(DIV_ROUND_UP(I3C_BUS_TLOW_OD_MIN_NS, core_period), lcnt); 545 scl_timing = SCL_I3C_TIMING_HCNT(hcnt) | SCL_I3C_TIMING_LCNT(lcnt); 546 writel(scl_timing, master->regs + SCL_I3C_OD_TIMING); 547 548 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR1_SCL_RATE) - hcnt; 549 scl_timing = SCL_EXT_LCNT_1(lcnt); 550 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR2_SCL_RATE) - hcnt; 551 scl_timing |= SCL_EXT_LCNT_2(lcnt); 552 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR3_SCL_RATE) - hcnt; 553 scl_timing |= SCL_EXT_LCNT_3(lcnt); 554 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR4_SCL_RATE) - hcnt; 555 scl_timing |= SCL_EXT_LCNT_4(lcnt); 556 writel(scl_timing, master->regs + SCL_EXT_LCNT_TIMING); 557 558 return 0; 559 } 560 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
Thanks Intel kernel test robot. This patch was meant for i3c tree. And I have submitted a new V2 patch which replaced max with max_t to do the type cast.
Thanks Intel kernel test robot. I have submitted the V2 patch, which replaced max with max_t to do a type cast. On Mon, Feb 13, 2023 at 9:13 PM kernel test robot <lkp@intel.com> wrote: > > Hi Jack, > > Thank you for the patch! Perhaps something to improve: > > [auto build test WARNING on linus/master] > [also build test WARNING on v6.2-rc8 next-20230213] > [If your patch is applied to the wrong git tree, kindly drop us a note. > And when submitting patch, we suggest to use '--base' as documented in > https://git-scm.com/docs/git-format-patch#_base_tree_information] > > url: https://github.com/intel-lab-lkp/linux/commits/Jack-Chen/i3c-update-dw-i3c-master-i3c_clk_cfg-function/20230213-222533 > patch link: https://lore.kernel.org/r/20230213142336.192875-1-zenghuchen%40google.com > patch subject: [PATCH] i3c: update dw-i3c-master i3c_clk_cfg function > config: i386-randconfig-s001 (https://download.01.org/0day-ci/archive/20230214/202302141029.2CS1z9de-lkp@intel.com/config) > compiler: gcc-11 (Debian 11.3.0-8) 11.3.0 > reproduce: > # apt-get install sparse > # sparse version: v0.6.4-39-gce1a6720-dirty > # https://github.com/intel-lab-lkp/linux/commit/e85b41ae5bb17077ac7d01bdd13c48ea1f83ea42 > git remote add linux-review https://github.com/intel-lab-lkp/linux > git fetch --no-tags linux-review Jack-Chen/i3c-update-dw-i3c-master-i3c_clk_cfg-function/20230213-222533 > git checkout e85b41ae5bb17077ac7d01bdd13c48ea1f83ea42 > # save the config file > mkdir build_dir && cp config build_dir/.config > make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 olddefconfig > make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=i386 SHELL=/bin/bash drivers/i3c/master/ > > If you fix the issue, kindly add following tag where applicable > | Reported-by: kernel test robot <lkp@intel.com> > | Link: https://lore.kernel.org/oe-kbuild-all/202302141029.2CS1z9de-lkp@intel.com/ > > sparse warnings: (new ones prefixed by >>) > >> drivers/i3c/master/dw-i3c-master.c:544:16: sparse: sparse: incompatible types in comparison expression (different type sizes): > >> drivers/i3c/master/dw-i3c-master.c:544:16: sparse: unsigned long * > >> drivers/i3c/master/dw-i3c-master.c:544:16: sparse: unsigned char * > > vim +544 drivers/i3c/master/dw-i3c-master.c > > 517 > 518 static int dw_i3c_clk_cfg(struct dw_i3c_master *master) > 519 { > 520 unsigned long core_rate, core_period; > 521 u32 scl_timing; > 522 u8 hcnt, lcnt; > 523 > 524 core_rate = clk_get_rate(master->core_clk); > 525 if (!core_rate) > 526 return -EINVAL; > 527 > 528 core_period = DIV_ROUND_UP(1000000000, core_rate); > 529 > 530 hcnt = DIV_ROUND_UP(I3C_BUS_THIGH_MAX_NS, core_period) - 1; > 531 if (hcnt < SCL_I3C_TIMING_CNT_MIN) > 532 hcnt = SCL_I3C_TIMING_CNT_MIN; > 533 > 534 lcnt = DIV_ROUND_UP(core_rate, master->base.bus.scl_rate.i3c) - hcnt; > 535 if (lcnt < SCL_I3C_TIMING_CNT_MIN) > 536 lcnt = SCL_I3C_TIMING_CNT_MIN; > 537 > 538 scl_timing = SCL_I3C_TIMING_HCNT(hcnt) | SCL_I3C_TIMING_LCNT(lcnt); > 539 writel(scl_timing, master->regs + SCL_I3C_PP_TIMING); > 540 > 541 if (!(readl(master->regs + DEVICE_CTRL) & DEV_CTRL_I2C_SLAVE_PRESENT)) > 542 writel(BUS_I3C_MST_FREE(lcnt), master->regs + BUS_FREE_TIMING); > 543 > > 544 lcnt = max(DIV_ROUND_UP(I3C_BUS_TLOW_OD_MIN_NS, core_period), lcnt); > 545 scl_timing = SCL_I3C_TIMING_HCNT(hcnt) | SCL_I3C_TIMING_LCNT(lcnt); > 546 writel(scl_timing, master->regs + SCL_I3C_OD_TIMING); > 547 > 548 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR1_SCL_RATE) - hcnt; > 549 scl_timing = SCL_EXT_LCNT_1(lcnt); > 550 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR2_SCL_RATE) - hcnt; > 551 scl_timing |= SCL_EXT_LCNT_2(lcnt); > 552 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR3_SCL_RATE) - hcnt; > 553 scl_timing |= SCL_EXT_LCNT_3(lcnt); > 554 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR4_SCL_RATE) - hcnt; > 555 scl_timing |= SCL_EXT_LCNT_4(lcnt); > 556 writel(scl_timing, master->regs + SCL_EXT_LCNT_TIMING); > 557 > 558 return 0; > 559 } > 560 > > -- > 0-DAY CI Kernel Test Service > https://github.com/intel/lkp-tests
Hi Jack, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v6.2-rc8 next-20230213] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Jack-Chen/i3c-update-dw-i3c-master-i3c_clk_cfg-function/20230213-222533 patch link: https://lore.kernel.org/r/20230213142336.192875-1-zenghuchen%40google.com patch subject: [PATCH] i3c: update dw-i3c-master i3c_clk_cfg function config: hexagon-randconfig-r041-20230213 (https://download.01.org/0day-ci/archive/20230214/202302140331.EVRBei1L-lkp@intel.com/config) compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project db89896bbbd2251fff457699635acbbedeead27f) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/intel-lab-lkp/linux/commit/e85b41ae5bb17077ac7d01bdd13c48ea1f83ea42 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Jack-Chen/i3c-update-dw-i3c-master-i3c_clk_cfg-function/20230213-222533 git checkout e85b41ae5bb17077ac7d01bdd13c48ea1f83ea42 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/i3c/master/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@intel.com> | Link: https://lore.kernel.org/oe-kbuild-all/202302140331.EVRBei1L-lkp@intel.com/ All warnings (new ones prefixed by >>): In file included from drivers/i3c/master/dw-i3c-master.c:13: In file included from include/linux/i3c/master.h:14: In file included from include/linux/i2c.h:19: In file included from include/linux/regulator/consumer.h:35: In file included from include/linux/suspend.h:5: In file included from include/linux/swap.h:9: In file included from include/linux/memcontrol.h:13: In file included from include/linux/cgroup.h:26: In file included from include/linux/kernel_stat.h:9: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __raw_readb(PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu' #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) ^ In file included from drivers/i3c/master/dw-i3c-master.c:13: In file included from include/linux/i3c/master.h:14: In file included from include/linux/i2c.h:19: In file included from include/linux/regulator/consumer.h:35: In file included from include/linux/suspend.h:5: In file included from include/linux/swap.h:9: In file included from include/linux/memcontrol.h:13: In file included from include/linux/cgroup.h:26: In file included from include/linux/kernel_stat.h:9: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) ^ In file included from drivers/i3c/master/dw-i3c-master.c:13: In file included from include/linux/i3c/master.h:14: In file included from include/linux/i2c.h:19: In file included from include/linux/regulator/consumer.h:35: In file included from include/linux/suspend.h:5: In file included from include/linux/swap.h:9: In file included from include/linux/memcontrol.h:13: In file included from include/linux/cgroup.h:26: In file included from include/linux/kernel_stat.h:9: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writeb(value, PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ >> drivers/i3c/master/dw-i3c-master.c:544:9: warning: comparison of distinct pointer types ('typeof ((((200) + (core_period) - 1) / (core_period))) *' (aka 'unsigned long *') and 'typeof (lcnt) *' (aka 'unsigned char *')) [-Wcompare-distinct-pointer-types] lcnt = max(DIV_ROUND_UP(I3C_BUS_TLOW_OD_MIN_NS, core_period), lcnt); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:74:19: note: expanded from macro 'max' #define max(x, y) __careful_cmp(x, y, >) ^~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp' __builtin_choose_expr(__safe_cmp(x, y), \ ^~~~~~~~~~~~~~~~ include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp' (__typecheck(x, y) && __no_side_effects(x, y)) ^~~~~~~~~~~~~~~~~ include/linux/minmax.h:20:28: note: expanded from macro '__typecheck' (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) ~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~ 7 warnings generated. vim +544 drivers/i3c/master/dw-i3c-master.c 517 518 static int dw_i3c_clk_cfg(struct dw_i3c_master *master) 519 { 520 unsigned long core_rate, core_period; 521 u32 scl_timing; 522 u8 hcnt, lcnt; 523 524 core_rate = clk_get_rate(master->core_clk); 525 if (!core_rate) 526 return -EINVAL; 527 528 core_period = DIV_ROUND_UP(1000000000, core_rate); 529 530 hcnt = DIV_ROUND_UP(I3C_BUS_THIGH_MAX_NS, core_period) - 1; 531 if (hcnt < SCL_I3C_TIMING_CNT_MIN) 532 hcnt = SCL_I3C_TIMING_CNT_MIN; 533 534 lcnt = DIV_ROUND_UP(core_rate, master->base.bus.scl_rate.i3c) - hcnt; 535 if (lcnt < SCL_I3C_TIMING_CNT_MIN) 536 lcnt = SCL_I3C_TIMING_CNT_MIN; 537 538 scl_timing = SCL_I3C_TIMING_HCNT(hcnt) | SCL_I3C_TIMING_LCNT(lcnt); 539 writel(scl_timing, master->regs + SCL_I3C_PP_TIMING); 540 541 if (!(readl(master->regs + DEVICE_CTRL) & DEV_CTRL_I2C_SLAVE_PRESENT)) 542 writel(BUS_I3C_MST_FREE(lcnt), master->regs + BUS_FREE_TIMING); 543 > 544 lcnt = max(DIV_ROUND_UP(I3C_BUS_TLOW_OD_MIN_NS, core_period), lcnt); 545 scl_timing = SCL_I3C_TIMING_HCNT(hcnt) | SCL_I3C_TIMING_LCNT(lcnt); 546 writel(scl_timing, master->regs + SCL_I3C_OD_TIMING); 547 548 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR1_SCL_RATE) - hcnt; 549 scl_timing = SCL_EXT_LCNT_1(lcnt); 550 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR2_SCL_RATE) - hcnt; 551 scl_timing |= SCL_EXT_LCNT_2(lcnt); 552 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR3_SCL_RATE) - hcnt; 553 scl_timing |= SCL_EXT_LCNT_3(lcnt); 554 lcnt = DIV_ROUND_UP(core_rate, I3C_BUS_SDR4_SCL_RATE) - hcnt; 555 scl_timing |= SCL_EXT_LCNT_4(lcnt); 556 writel(scl_timing, master->regs + SCL_EXT_LCNT_TIMING); 557 558 return 0; 559 } 560 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
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