Re: [PATCH v2 6/7] phy: qualcomm: phy-qcom-qmp-ufs: Add High Speed Gear 5 support for SM8550

Manivannan Sadhasivam
2023-11-14T06:12:26Z

On Sun, Nov 12, 2023 at 01:13:30PM +0800, Can Guo wrote:
> Hi Mani,
>
> On 11/11/2023 12:12 PM, Manivannan Sadhasivam wrote:
> > On Fri, Nov 10, 2023 at 10:40:53PM +0800, Can Guo wrote:
> > >
> > >
> > > On 11/10/2023 9:18 PM, Manivannan Sadhasivam wrote:
> > > > On Fri, Nov 10, 2023 at 12:11:46AM +0200, Dmitry Baryshkov wrote:
> > > > > On Thu, 9 Nov 2023 at 18:04, Manivannan Sadhasivam <mani@kernel.org> wrote:
> > > > > >
> > > > > > On Thu, Nov 09, 2023 at 01:00:51PM +0200, Dmitry Baryshkov wrote:
> > > > > > > On Thu, 9 Nov 2023 at 12:43, Manivannan Sadhasivam <mani@kernel.org> wrote:
> > > > > > > >
> > > > > > > > On Thu, Nov 09, 2023 at 11:40:51AM +0200, Dmitry Baryshkov wrote:
> > > > > > > > > On Thu, 9 Nov 2023 at 05:24, Manivannan Sadhasivam <mani@kernel.org> wrote:
> > > > > > > > > >
> > > > > > > > > > On Wed, Nov 08, 2023 at 08:56:16AM +0200, Dmitry Baryshkov wrote:
> > > > > > > > > > > On Wed, 8 Nov 2023 at 07:49, Manivannan Sadhasivam <mani@kernel.org> wrote:
> > > > > > > > > > > >
> > > > > > > > > > > > On Tue, Nov 07, 2023 at 03:18:09PM +0200, Dmitry Baryshkov wrote:
> > > > > > > > > > > > > On Tue, 7 Nov 2023 at 06:47, Can Guo <cang@qti.qualcomm.com> wrote:
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > From: Can Guo <quic_cang@quicinc.com>
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > On SM8550, two sets of UFS PHY settings are provided, one set is to support
> > > > > > > > > > > > > > HS-G5, another set is to support HS-G4 and lower gears. The two sets of PHY
> > > > > > > > > > > > > > settings are programming different values to different registers, mixing
> > > > > > > > > > > > > > the two sets and/or overwriting one set with another set is definitely not
> > > > > > > > > > > > > > blessed by UFS PHY designers. In order to add HS-G5 support for SM8550, we
> > > > > > > > > > > > > > need to split the two sets into their dedicated tables, and leave only the
> > > > > > > > > > > > > > common settings in the .tlbs. To have the PHY programmed with the correct
> > > > > > > > > > > > > > set of PHY settings, the submode passed to PHY driver must be either HS-G4
> > > > > > > > > > > > > > or HS-G5.
> > > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > > > You should also mention that this issue is also present in G4 supported targets.
> > > > > > > > > > > > And a note that it will get fixed later.
> > > > > > > > > > > >
> > > > > > > > > > > > > > Signed-off-by: Can Guo <quic_cang@quicinc.com>
> > > > > > > > > > > > > > ---
> > > > > > > > > > > > > > drivers/phy/qualcomm/phy-qcom-qmp-pcs-ufs-v6.h | 2 +
> > > > > > > > > > > > > > drivers/phy/qualcomm/phy-qcom-qmp-qserdes-com-v6.h | 2 +
> > > > > > > > > > > > > > .../qualcomm/phy-qcom-qmp-qserdes-txrx-ufs-v6.h | 12 +++
> > > > > > > > > > > > > > drivers/phy/qualcomm/phy-qcom-qmp-ufs.c | 112 ++++++++++++++++++---
> > > > > > > > > > > > > > 4 files changed, 115 insertions(+), 13 deletions(-)
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-pcs-ufs-v6.h b/drivers/phy/qualcomm/phy-qcom-qmp-pcs-ufs-v6.h
> > > > > > > > > > > > > > index c23d5e4..e563af5 100644
> > > > > > > > > > > > > > --- a/drivers/phy/qualcomm/phy-qcom-qmp-pcs-ufs-v6.h
> > > > > > > > > > > > > > +++ b/drivers/phy/qualcomm/phy-qcom-qmp-pcs-ufs-v6.h
> > > > > > > > > > > > > > @@ -18,6 +18,7 @@
> > > > > > > > > > > > > > #define QPHY_V6_PCS_UFS_BIST_FIXED_PAT_CTRL 0x060
> > > > > > > > > > > > > > #define QPHY_V6_PCS_UFS_TX_HSGEAR_CAPABILITY 0x074
> > > > > > > > > > > > > > #define QPHY_V6_PCS_UFS_RX_HSGEAR_CAPABILITY 0x0bc
> > > > > > > > > > > > > > +#define QPHY_V6_PCS_UFS_RX_HS_G5_SYNC_LENGTH_CAPABILITY 0x12c
> > > > > > > > > > > > > > #define QPHY_V6_PCS_UFS_DEBUG_BUS_CLKSEL 0x158
> > > > > > > > > > > > > > #define QPHY_V6_PCS_UFS_LINECFG_DISABLE 0x17c
> > > > > > > > > > > > > > #define QPHY_V6_PCS_UFS_RX_MIN_HIBERN8_TIME 0x184
> > > > > > > > > > > > > > @@ -27,5 +28,6 @@
> > > > > > > > > > > > > > #define QPHY_V6_PCS_UFS_READY_STATUS 0x1a8
> > > > > > > > > > > > > > #define QPHY_V6_PCS_UFS_TX_MID_TERM_CTRL1 0x1f4
> > > > > > > > > > > > > > #define QPHY_V6_PCS_UFS_MULTI_LANE_CTRL1 0x1fc
> > > > > > > > > > > > > > +#define QPHY_V6_PCS_UFS_RX_HSG5_SYNC_WAIT_TIME 0x220
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > #endif
> > > > > > > > > > > > > > diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-qserdes-com-v6.h b/drivers/phy/qualcomm/phy-qcom-qmp-qserdes-com-v6.h
> > > > > > > > > > > > > > index f420f8f..ef392ce 100644
> > > > > > > > > > > > > > --- a/drivers/phy/qualcomm/phy-qcom-qmp-qserdes-com-v6.h
> > > > > > > > > > > > > > +++ b/drivers/phy/qualcomm/phy-qcom-qmp-qserdes-com-v6.h
> > > > > > > > > > > > > > @@ -56,6 +56,8 @@
> > > > > > > > > > > > > > #define QSERDES_V6_COM_SYS_CLK_CTRL 0xe4
> > > > > > > > > > > > > > #define QSERDES_V6_COM_SYSCLK_BUF_ENABLE 0xe8
> > > > > > > > > > > > > > #define QSERDES_V6_COM_PLL_IVCO 0xf4
> > > > > > > > > > > > > > +#define QSERDES_V6_COM_CMN_IETRIM 0xfc
> > > > > > > > > > > > > > +#define QSERDES_V6_COM_CMN_IPTRIM 0x100
> > > > > > > > > > > > > > #define QSERDES_V6_COM_SYSCLK_EN_SEL 0x110
> > > > > > > > > > > > > > #define QSERDES_V6_COM_RESETSM_CNTRL 0x118
> > > > > > > > > > > > > > #define QSERDES_V6_COM_LOCK_CMP_EN 0x120
> > > > > > > > > > > > > > diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-qserdes-txrx-ufs-v6.h b/drivers/phy/qualcomm/phy-qcom-qmp-qserdes-txrx-ufs-v6.h
> > > > > > > > > > > > > > index 15bcb4b..48f31c8 100644
> > > > > > > > > > > > > > --- a/drivers/phy/qualcomm/phy-qcom-qmp-qserdes-txrx-ufs-v6.h
> > > > > > > > > > > > > > +++ b/drivers/phy/qualcomm/phy-qcom-qmp-qserdes-txrx-ufs-v6.h
> > > > > > > > > > > > > > @@ -10,10 +10,20 @@
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_TX_RES_CODE_LANE_RX 0x2c
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_TX_RES_CODE_LANE_OFFSET_TX 0x30
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_TX_RES_CODE_LANE_OFFSET_RX 0x34
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_TX_LANE_MODE_1 0x7c
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_TX_FR_DCC_CTRL 0x108
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_UCDR_FASTLOCK_FO_GAIN_RATE2 0x08
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_UCDR_FASTLOCK_FO_GAIN_RATE4 0x10
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_UCDR_FASTLOCK_SO_GAIN_RATE4 0x24
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_UCDR_FASTLOCK_COUNT_HIGH_RATE4 0x54
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_UCDR_FO_GAIN_RATE2 0xd4
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_UCDR_FO_GAIN_RATE4 0xdc
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_UCDR_SO_GAIN_RATE4 0xf0
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_UCDR_PI_CONTROLS 0xf4
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_VGA_CAL_MAN_VAL 0x178
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_EQ_OFFSET_ADAPTOR_CNTRL1 0x1bc
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_OFFSET_ADAPTOR_CNTRL3 0x1c4
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_MODE_RATE_0_1_B0 0x208
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_MODE_RATE_0_1_B1 0x20c
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_MODE_RATE_0_1_B3 0x214
> > > > > > > > > > > > > > @@ -25,6 +35,8 @@
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_MODE_RATE3_B5 0x264
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_MODE_RATE3_B8 0x270
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_MODE_RATE4_B3 0x280
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_MODE_RATE4_B4 0x284
> > > > > > > > > > > > > > #define QSERDES_UFS_V6_RX_MODE_RATE4_B6 0x28c
> > > > > > > > > > > > > > +#define QSERDES_UFS_V6_RX_DLL0_FTUNE_CTRL 0x2f8
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > #endif
> > > > > > > > > > > > > > diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> > > > > > > > > > > > > > index 3927eba..e0a01497 100644
> > > > > > > > > > > > > > --- a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> > > > > > > > > > > > > > +++ b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> > > > > > > > > > > > > > @@ -649,32 +649,51 @@ static const struct qmp_phy_init_tbl sm8550_ufsphy_serdes[] = {
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_HSCLK_SEL_1, 0x11),
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_HSCLK_HS_SWITCH_SEL_1, 0x00),
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_LOCK_CMP_EN, 0x01),
> > > > > > > > > > > > > > - QMP_PHY_INIT_CFG(QSERDES_V6_COM_VCO_TUNE_MAP, 0x04),
> > > > > > > > > > > > > > - QMP_PHY_INIT_CFG(QSERDES_V6_COM_PLL_IVCO, 0x0f),
> > > > > > > > > > > > > > +
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_VCO_TUNE_INITVAL2, 0x00),
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_DEC_START_MODE0, 0x41),
> > > > > > > > > > > > > > - QMP_PHY_INIT_CFG(QSERDES_V6_COM_CP_CTRL_MODE0, 0x0a),
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_PLL_RCTRL_MODE0, 0x18),
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_PLL_CCTRL_MODE0, 0x14),
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_LOCK_CMP1_MODE0, 0x7f),
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_LOCK_CMP2_MODE0, 0x06),
> > > > > > > > > > > > > > - QMP_PHY_INIT_CFG(QSERDES_V6_COM_DEC_START_MODE0, 0x4c),
> > > > > > > > > > > > > > +};
> > > > > > > > > > > > > > +
> > > > > > > > > > > > > > +static const struct qmp_phy_init_tbl sm8550_ufsphy_hs_b_serdes[] = {
> > > > > > > > > > > > > > + QMP_PHY_INIT_CFG(QSERDES_V6_COM_VCO_TUNE_MAP, 0x44),
> > > > > > > > > > > > > > +};
> > > > > > > > > > > > > > +
> > > > > > > > > > > > > > +static const struct qmp_phy_init_tbl sm8550_ufsphy_g4_serdes[] = {
> > > > > > > > > > > > > > + QMP_PHY_INIT_CFG(QSERDES_V6_COM_VCO_TUNE_MAP, 0x04),
> > > > > > > > > > > > > > + QMP_PHY_INIT_CFG(QSERDES_V6_COM_PLL_IVCO, 0x0f),
> > > > > > > > > > > > > > QMP_PHY_INIT_CFG(QSERDES_V6_COM_CP_CTRL_MODE0, 0x0a),
> > > > > > > > > > > > > > - QMP_PHY_INIT_CFG(QSERDES_V6_COM_PLL_RCTRL_MODE0, 0x18),
> > > > > > > > > > > > > > - QMP_PHY_INIT_CFG(QSERDES_V6_COM_PLL_CCTRL_MODE0, 0x14),
> > > > > > > > > > > > > > - QMP_PHY_INIT_CFG(QSERDES_V6_COM_LOCK_CMP1_MODE0, 0x99),
> > > > > > > > > > > > > > - QMP_PHY_INIT_CFG(QSERDES_V6_COM_LOCK_CMP2_MODE0, 0x07),
> > > > > > > > > > > > >
> > > > > > > > > > > > > Aside from moving these registers to the HS_G4 table, you are also
> > > > > > > > > > > > > changing these registers. It makes me think that there was an error in
> > > > > > > > > > > > > the original programming sequence.
> > > > > > > > > > > > > If that is correct, could you please split the patch into two pieces:
> > > > > > > > > > > > > - Fix programming sequence (add proper Fixes tags)
> > > > > > > > > > > > > - Split G4 and G5 tables.
> > > > > > > > > > > >
> > > > > > > > > > > > Ack
> > > > > > > > > > > >
> > > > > > > > > > > > >
> > > > > > > > > > > > > > +
> > > > > > > > > > > > > > + QMP_PHY_INIT_CFG(QSERDES_V6_COM_DEC_START_MODE1, 0x4c),
> > > > > > > > > > > > > > + QMP_PHY_INIT_CFG(QSERDES_V6_COM_CP_CTRL_MODE1, 0x0a),
> > > > > > > > > > > > > > + QMP_PHY_INIT_CFG(QSERDES_V6_COM_PLL_RCTRL_MODE1, 0x18),
> > > > > > > > > > > > > > + QMP_PHY_INIT_CFG(QSERDES_V6_COM_PLL_CCTRL_MODE1, 0x14),
> > > > > > > > > > > > > > + QMP_PHY_INIT_CFG(QSERDES_V6_COM_LOCK_CMP1_MODE1, 0x99),
> > > > > > > > > > > > > > + QMP_PHY_INIT_CFG(QSERDES_V6_COM_LOCK_CMP2_MODE1, 0x07),
> > > > > > > > > > > > >
> > > > > > > > > > > > > I see all the MODE1 registers being only present in G4 and G5 tables.
> > > > > > > > > > > > > Should they be programmed for the modes lower than G4?
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > > > We use G4 table for all the modes <= G4.
> > > > > > > > > > >
> > > > > > > > > > > Could you please point me how it's handled?
> > > > > > > > > > > In the patch I see just:
> > > > > > > > > > >
> > > > > > > > > > > if (qmp->submode == UFS_HS_G4)
> > > > > > > > > > > qmp_ufs_serdes_init(qmp, &cfg->tbls_hs_g4);
> > > > > > > > > > > else if (qmp->submode == UFS_HS_G5)
> > > > > > > > > > > qmp_ufs_serdes_init(qmp, &cfg->tbls_hs_g5);
> > > > > > > > > > >
> > > > > > > > > > > Which looks like two special cases (HS_G4 and HS_G5) and nothing for
> > > > > > > > > > > anything else.
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > > Yes, and the UFS driver passes only G4/G5. For all the gears <=G4, G4 init
> > > > > > > > > > sequence will be used and for G5, G5 sequence will be used.
> > > > > > > > > >
> > > > > > > > >
> > > > > > > > > That's what I could not find in the UFS driver. I see a call to
> > > > > > > > > `phy_set_mode_ext(phy, PHY_MODE_UFS_HS_B, host->phy_gear);` and
> > > > > > > > > host->phy_gear is initialised to UFS_HS_G2.
> > > > > > > > >
> > > > > > > >
> > > > > > > > You need to check the UFS driver changes in this series to get the complete
> > > > > > > > picture as the logic is getting changed.
> > > > > > > >
> > > > > > > > It is common to get confused because of the way the UFS driver (qcom mostly)
> > > > > > > > handles the PHY init sequence programming. We used to have only one init
> > > > > > > > sequence for older targets and life was easy. But when I wanted to add G4
> > > > > > > > support for SM8250, I learned that there are 2 separate init sequences. One for
> > > > > > > > non-G4 and other for G4. So I used the phy_sub_mode property to pass the
> > > > > > > > relevant mode from the UFS driver to the PHY driver and programmed the sequence
> > > > > > > > accordingly. This got extended to non-G5 and G5 now.
> > > > > > > >
> > > > > > > > Now, the UFS driver will start probing from a low gear for older targets (G2)
> > > > > > > > and G4/G5 for newer ones then scale up based on the device and host capability.
> > > > > > > > For older targets, the common table (tbls) will be used if the submode doesn't
> > > > > > > > match G4/G5. But for newer targets, the UFS driver will _only_ pass G4 or G5 as
> > > > > > > > the phy_gear, so those specific sequence will only be used.
> > > > > > > >
> > > > > > > > Hope I'm clear.
> > > > > > >
> > > > > > > Yes, it is now clear, thank you!
> > > > > > >
> > > > > > > Would it be possible / feasible / logical to maintain this idea even
> > > > > > > for newer platforms (leaving the HS_A / HS_B aside)?
> > > > > > >
> > > > > > > tbls - works for HS_G2
> > > > > > > tbls + tbls_g4 - works for HS_G4
> > > > > > > tbls + tbls_g5 - works for HS_G5
> > > > > > >
> > > > > >
> > > > > > No. The PHY team only gives 2 init sequences for any SoC now.
> > > > >
> > > > > Ack. Then the code should become
> > > > > if (HS_G5)
> > > > > program(tbls_hs_g5)
> > > > > else
> > > > > program(tbls_hs_g4);
> > > > >
> > > >
> > > > This should work. Even if we have to accomodate G6 in the future, we can use
> > > > "else if" for that and keep G4 as the "else" condition. This logic can also be
> > > > optimized in the future.
> > >
> > > That would make dual init meaningless for old targets. Say on SM8450, the
> > > initial PHY gear is G2, with the "else" condition, during the first init, G4
> > > table would be programmed, then gear negotiation happens btw host and device
> > > and the negotiated gear is G3 (assume a UFS2.x is connected). During the 2nd
> > > init, the "else" condition would __again__ program the G4 table - it is not
> > > programming the non-G4 table for power saving. The dual init is supposed to
> > > find the optimal PHY settings, but the "else" condition is programming G4
> > > table unconditinally.
> > >
> > > With the original code change in this patch, the dual init works as it is
> > > for old targets. say SM8450, the initial PHY gear is G2, during the 2nd
> > > init, it is programming the non-G4 table (assume a UFS2.x is connected), but
> > > not the G4 table.
> > >
> >
> > You are right. I completely overlooked the compatibility for old targets. But
> > still we can move the common table to the "else" condition. This makes it clear
> > that one of the 3 will be programmed at a time. But with the current logic, I
> > get the impression that common table is overridden by G4/G5 tables.
> >
> > So this is what I'm suggesting:
> >
> > if (HS_G5)
> > program(tbls_hs_g5)
> > else if (HS_G4)
> > program(tbls_hs_g4);
> > else
> > program(tbls_hs_common);
> >
>
> Common table is needed regardlessly, we cannot put it in "else", otherwise
> it would break all targets -
>
> On old targets (no G5 supported):
> Common table - supports non-G4 (G3 and lower)
> Common table + G4 table - supports G4
>
> On new targets (G5 supported):
> Common table - supports nothing, as it is just common parts of G4 table
> and G5 table.
> Common table + G4 table - support non-G5 (G4 and lower)
> Common table + G5 table - support G5
>

Doh! I missed the fact that common table is not a standalone table. Sorry for
the confusion. Let's keep it as you proposed for now. I still don't like the if
conditions as it would just keep growing with future gears, but we can get to it
later.

- Mani

> Thanks,
> Can Guo.
>
> > - Mani
> >
> > > Thanks,
> > > Can Guo.
> > > >
> > > > - Mani
> > > >
> > > > > >
> > > > > > - Mani
> > > > > >
> > > > > > > I mean here that the PHY driver should not depend on the knowledge
> > > > > > > that the UFS driver will not be setting HS_G2 for some particular
> > > > > > > platform and ideally it should continue working if at some point we
> > > > > > > change the UFS driver to set HS_G2.
> > > > > > >
> > > > > > >
> > > > > > > >
> > > > > > > > - Mani
> > > > > > > >
> > > > > > > > > Maybe we should change the condition here (in the PHY driver) to:
> > > > > > > > >
> > > > > > > > > if (qmp->submode <= UFS_HS_G4)
> > > > > > > > >
> > > > > > > > > ?
> > > > > > > > > --
> > > > > > > > > With best wishes
> > > > > > > > > Dmitry
> > > > > > > >
> > > > > > > > --
> > > > > > > > மணிவண்ணன் சதாசிவம்
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > --
> > > > > > > With best wishes
> > > > > > > Dmitry
> > > > > >
> > > > > > --
> > > > > > மணிவண்ணன் சதாசிவம்
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > With best wishes
> > > > > Dmitry
> > > >
> >

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மணிவண்ணன் சதாசிவம்