1c8284409SSoren Brinkmann /* 2*619bc13eSMichal Simek * Copyright (c) 2013-2018, Arm Limited and Contributors. All rights reserved. 3a92681d9SJay Buddhabhatti * Copyright (c) 2022-2023, Advanced Micro Devices, Inc. All rights reserved. 4c8284409SSoren Brinkmann * 582cb2c1aSdp-arm * SPDX-License-Identifier: BSD-3-Clause 6c8284409SSoren Brinkmann */ 7c8284409SSoren Brinkmann 8c8284409SSoren Brinkmann /* 9c8284409SSoren Brinkmann * APU specific definition of processors in the subsystem as well as functions 10c8284409SSoren Brinkmann * for getting information about and changing state of the APU. 11c8284409SSoren Brinkmann */ 12c8284409SSoren Brinkmann 13b516b7dcSFilip Drazic #include <assert.h> 14b516b7dcSFilip Drazic #include <string.h> 1509d40e0eSAntonio Nino Diaz 1609d40e0eSAntonio Nino Diaz #include <common/bl_common.h> 1709d40e0eSAntonio Nino Diaz #include <drivers/arm/gic_common.h> 1809d40e0eSAntonio Nino Diaz #include <drivers/arm/gicv2.h> 1909d40e0eSAntonio Nino Diaz #include <lib/bakery_lock.h> 2009d40e0eSAntonio Nino Diaz #include <lib/mmio.h> 2109d40e0eSAntonio Nino Diaz #include <lib/utils.h> 2209d40e0eSAntonio Nino Diaz 2365c80d60SJolly Shah #include <plat_ipi.h> 2499564393SJolly Shah #include <zynqmp_def.h> 25c8284409SSoren Brinkmann #include "pm_client.h" 26c8284409SSoren Brinkmann #include "pm_ipi.h" 27a92681d9SJay Buddhabhatti #include "zynqmp_pm_api_sys.h" 28c8284409SSoren Brinkmann 29c8890883SHariBabu Gattem #define IRQ_MAX 84U 30c8890883SHariBabu Gattem #define NUM_GICD_ISENABLER ((IRQ_MAX >> 5U) + 1U) 31c8890883SHariBabu Gattem #define UNDEFINED_CPUID (~0U) 3295fd990fSFilip Drazic 33c8890883SHariBabu Gattem #define PM_SUSPEND_MODE_STD 0U 34c8890883SHariBabu Gattem #define PM_SUSPEND_MODE_POWER_OFF 1U 3534c57139SSiva Durga Prasad Paladugu 3603b80773SStefan Krsmanovic DEFINE_BAKERY_LOCK(pm_client_secure_lock); 37c8284409SSoren Brinkmann 38c8284409SSoren Brinkmann extern const struct pm_ipi apu_ipi; 39c8284409SSoren Brinkmann 4065c80d60SJolly Shah const struct pm_ipi apu_ipi = { 4165c80d60SJolly Shah .local_ipi_id = IPI_ID_APU, 4265c80d60SJolly Shah .remote_ipi_id = IPI_ID_PMU0, 4365c80d60SJolly Shah .buffer_base = IPI_BUFFER_APU_BASE, 4465c80d60SJolly Shah }; 4565c80d60SJolly Shah 4634c57139SSiva Durga Prasad Paladugu static uint32_t suspend_mode = PM_SUSPEND_MODE_STD; 4734c57139SSiva Durga Prasad Paladugu 48c8284409SSoren Brinkmann /* Order in pm_procs_all array must match cpu ids */ 49a97f6272SSoren Brinkmann static const struct pm_proc pm_procs_all[] = { 50c8284409SSoren Brinkmann { 51c8284409SSoren Brinkmann .node_id = NODE_APU_0, 52c8284409SSoren Brinkmann .pwrdn_mask = APU_0_PWRCTL_CPUPWRDWNREQ_MASK, 53c8284409SSoren Brinkmann .ipi = &apu_ipi, 54c8284409SSoren Brinkmann }, 55c8284409SSoren Brinkmann { 56c8284409SSoren Brinkmann .node_id = NODE_APU_1, 57c8284409SSoren Brinkmann .pwrdn_mask = APU_1_PWRCTL_CPUPWRDWNREQ_MASK, 58c8284409SSoren Brinkmann .ipi = &apu_ipi, 59c8284409SSoren Brinkmann }, 60c8284409SSoren Brinkmann { 61c8284409SSoren Brinkmann .node_id = NODE_APU_2, 62c8284409SSoren Brinkmann .pwrdn_mask = APU_2_PWRCTL_CPUPWRDWNREQ_MASK, 63c8284409SSoren Brinkmann .ipi = &apu_ipi, 64c8284409SSoren Brinkmann }, 65c8284409SSoren Brinkmann { 66c8284409SSoren Brinkmann .node_id = NODE_APU_3, 67c8284409SSoren Brinkmann .pwrdn_mask = APU_3_PWRCTL_CPUPWRDWNREQ_MASK, 68c8284409SSoren Brinkmann .ipi = &apu_ipi, 69c8284409SSoren Brinkmann }, 70c8284409SSoren Brinkmann }; 71c8284409SSoren Brinkmann 72b516b7dcSFilip Drazic /* Interrupt to PM node ID map */ 73c8890883SHariBabu Gattem static enum pm_node_id irq_node_map[IRQ_MAX + 1U] = { 74b516b7dcSFilip Drazic NODE_UNKNOWN, 75b516b7dcSFilip Drazic NODE_UNKNOWN, 76b516b7dcSFilip Drazic NODE_UNKNOWN, 77b516b7dcSFilip Drazic NODE_UNKNOWN, /* 3 */ 78b516b7dcSFilip Drazic NODE_UNKNOWN, 79b516b7dcSFilip Drazic NODE_UNKNOWN, 80b516b7dcSFilip Drazic NODE_UNKNOWN, 81b516b7dcSFilip Drazic NODE_UNKNOWN, /* 7 */ 82b516b7dcSFilip Drazic NODE_UNKNOWN, 83b516b7dcSFilip Drazic NODE_UNKNOWN, 84b516b7dcSFilip Drazic NODE_UNKNOWN, 85b516b7dcSFilip Drazic NODE_UNKNOWN, /* 11 */ 86b516b7dcSFilip Drazic NODE_UNKNOWN, 87b516b7dcSFilip Drazic NODE_UNKNOWN, 88b516b7dcSFilip Drazic NODE_NAND, 89b516b7dcSFilip Drazic NODE_QSPI, /* 15 */ 90b516b7dcSFilip Drazic NODE_GPIO, 91b516b7dcSFilip Drazic NODE_I2C_0, 92b516b7dcSFilip Drazic NODE_I2C_1, 93b516b7dcSFilip Drazic NODE_SPI_0, /* 19 */ 94b516b7dcSFilip Drazic NODE_SPI_1, 95b516b7dcSFilip Drazic NODE_UART_0, 96b516b7dcSFilip Drazic NODE_UART_1, 97b516b7dcSFilip Drazic NODE_CAN_0, /* 23 */ 98b516b7dcSFilip Drazic NODE_CAN_1, 99b516b7dcSFilip Drazic NODE_UNKNOWN, 100b516b7dcSFilip Drazic NODE_RTC, 101b516b7dcSFilip Drazic NODE_RTC, /* 27 */ 102b516b7dcSFilip Drazic NODE_UNKNOWN, 103b516b7dcSFilip Drazic NODE_UNKNOWN, 104b516b7dcSFilip Drazic NODE_UNKNOWN, 105b516b7dcSFilip Drazic NODE_UNKNOWN, /* 31 */ 106b516b7dcSFilip Drazic NODE_UNKNOWN, 107b516b7dcSFilip Drazic NODE_UNKNOWN, 108b516b7dcSFilip Drazic NODE_UNKNOWN, 109b516b7dcSFilip Drazic NODE_UNKNOWN, /* 35, NODE_IPI_APU */ 110b516b7dcSFilip Drazic NODE_TTC_0, 111b516b7dcSFilip Drazic NODE_TTC_0, 112b516b7dcSFilip Drazic NODE_TTC_0, 113b516b7dcSFilip Drazic NODE_TTC_1, /* 39 */ 114b516b7dcSFilip Drazic NODE_TTC_1, 115b516b7dcSFilip Drazic NODE_TTC_1, 116b516b7dcSFilip Drazic NODE_TTC_2, 117b516b7dcSFilip Drazic NODE_TTC_2, /* 43 */ 118b516b7dcSFilip Drazic NODE_TTC_2, 119b516b7dcSFilip Drazic NODE_TTC_3, 120b516b7dcSFilip Drazic NODE_TTC_3, 121b516b7dcSFilip Drazic NODE_TTC_3, /* 47 */ 122b516b7dcSFilip Drazic NODE_SD_0, 123b516b7dcSFilip Drazic NODE_SD_1, 124b516b7dcSFilip Drazic NODE_SD_0, 125b516b7dcSFilip Drazic NODE_SD_1, /* 51 */ 126b516b7dcSFilip Drazic NODE_UNKNOWN, 127b516b7dcSFilip Drazic NODE_UNKNOWN, 128b516b7dcSFilip Drazic NODE_UNKNOWN, 129b516b7dcSFilip Drazic NODE_UNKNOWN, /* 55 */ 130b516b7dcSFilip Drazic NODE_UNKNOWN, 131b516b7dcSFilip Drazic NODE_ETH_0, 132b516b7dcSFilip Drazic NODE_ETH_0, 133b516b7dcSFilip Drazic NODE_ETH_1, /* 59 */ 134b516b7dcSFilip Drazic NODE_ETH_1, 135b516b7dcSFilip Drazic NODE_ETH_2, 136b516b7dcSFilip Drazic NODE_ETH_2, 137b516b7dcSFilip Drazic NODE_ETH_3, /* 63 */ 138b516b7dcSFilip Drazic NODE_ETH_3, 139b516b7dcSFilip Drazic NODE_USB_0, 140b516b7dcSFilip Drazic NODE_USB_0, 141b516b7dcSFilip Drazic NODE_USB_0, /* 67 */ 142b516b7dcSFilip Drazic NODE_USB_0, 143b516b7dcSFilip Drazic NODE_USB_0, 144b516b7dcSFilip Drazic NODE_USB_1, 145b516b7dcSFilip Drazic NODE_USB_1, /* 71 */ 146b516b7dcSFilip Drazic NODE_USB_1, 147b516b7dcSFilip Drazic NODE_USB_1, 148b516b7dcSFilip Drazic NODE_USB_1, 149b516b7dcSFilip Drazic NODE_USB_0, /* 75 */ 150b516b7dcSFilip Drazic NODE_USB_0, 151b516b7dcSFilip Drazic NODE_ADMA, 152b516b7dcSFilip Drazic NODE_ADMA, 153b516b7dcSFilip Drazic NODE_ADMA, /* 79 */ 154b516b7dcSFilip Drazic NODE_ADMA, 155b516b7dcSFilip Drazic NODE_ADMA, 156b516b7dcSFilip Drazic NODE_ADMA, 157b516b7dcSFilip Drazic NODE_ADMA, /* 83 */ 158b516b7dcSFilip Drazic NODE_ADMA, 159b516b7dcSFilip Drazic }; 160b516b7dcSFilip Drazic 161b516b7dcSFilip Drazic /** 162b516b7dcSFilip Drazic * irq_to_pm_node - Get PM node ID corresponding to the interrupt number 163b516b7dcSFilip Drazic * @irq: Interrupt number 164b516b7dcSFilip Drazic * 165b516b7dcSFilip Drazic * Return: PM node ID corresponding to the specified interrupt 166b516b7dcSFilip Drazic */ 167ffa91031SVenkatesh Yadav Abbarapu static enum pm_node_id irq_to_pm_node(uint32_t irq) 168b516b7dcSFilip Drazic { 169b516b7dcSFilip Drazic assert(irq <= IRQ_MAX); 170b516b7dcSFilip Drazic return irq_node_map[irq]; 171b516b7dcSFilip Drazic } 172b516b7dcSFilip Drazic 173b516b7dcSFilip Drazic /** 174b516b7dcSFilip Drazic * pm_client_set_wakeup_sources - Set all slaves with enabled interrupts as wake 175b516b7dcSFilip Drazic * sources in the PMU firmware 176b516b7dcSFilip Drazic */ 177b516b7dcSFilip Drazic static void pm_client_set_wakeup_sources(void) 178b516b7dcSFilip Drazic { 179b516b7dcSFilip Drazic uint32_t reg_num; 180590519a8SHariBabu Gattem uint8_t pm_wakeup_nodes_set[NODE_MAX] = { 0 }; 181c8890883SHariBabu Gattem uintptr_t isenabler1 = BASE_GICD_BASE + GICD_ISENABLER + 4U; 182b516b7dcSFilip Drazic 18334c57139SSiva Durga Prasad Paladugu /* In case of power-off suspend, only NODE_EXTERN must be set */ 18434c57139SSiva Durga Prasad Paladugu if (suspend_mode == PM_SUSPEND_MODE_POWER_OFF) { 18534c57139SSiva Durga Prasad Paladugu enum pm_ret_status ret; 18634c57139SSiva Durga Prasad Paladugu 187c8890883SHariBabu Gattem ret = pm_set_wakeup_source(NODE_APU, NODE_EXTERN, 1U); 18834c57139SSiva Durga Prasad Paladugu /** 18934c57139SSiva Durga Prasad Paladugu * If NODE_EXTERN could not be set as wake source, proceed with 19034c57139SSiva Durga Prasad Paladugu * standard suspend (no one will wake the system otherwise) 19134c57139SSiva Durga Prasad Paladugu */ 192eb0d2b17SVenkatesh Yadav Abbarapu if (ret == PM_RET_SUCCESS) { 19334c57139SSiva Durga Prasad Paladugu return; 19434c57139SSiva Durga Prasad Paladugu } 195eb0d2b17SVenkatesh Yadav Abbarapu } 19634c57139SSiva Durga Prasad Paladugu 19732f0d3c6SDouglas Raillard zeromem(&pm_wakeup_nodes_set, sizeof(pm_wakeup_nodes_set)); 198b516b7dcSFilip Drazic 199c8890883SHariBabu Gattem for (reg_num = 0U; reg_num < NUM_GICD_ISENABLER; reg_num++) { 200b516b7dcSFilip Drazic uint32_t base_irq = reg_num << ISENABLER_SHIFT; 201c8890883SHariBabu Gattem uint32_t reg = mmio_read_32(isenabler1 + (reg_num << 2U)); 202b516b7dcSFilip Drazic 203c8890883SHariBabu Gattem if (reg == 0) { 204b516b7dcSFilip Drazic continue; 205eb0d2b17SVenkatesh Yadav Abbarapu } 206b516b7dcSFilip Drazic 207b516b7dcSFilip Drazic while (reg) { 208b516b7dcSFilip Drazic enum pm_node_id node; 209b516b7dcSFilip Drazic uint32_t idx, ret, irq, lowest_set = reg & (-reg); 210b516b7dcSFilip Drazic 211b516b7dcSFilip Drazic idx = __builtin_ctz(lowest_set); 212b516b7dcSFilip Drazic irq = base_irq + idx; 213b516b7dcSFilip Drazic 214eb0d2b17SVenkatesh Yadav Abbarapu if (irq > IRQ_MAX) { 215b516b7dcSFilip Drazic break; 216eb0d2b17SVenkatesh Yadav Abbarapu } 217b516b7dcSFilip Drazic 218b516b7dcSFilip Drazic node = irq_to_pm_node(irq); 219b516b7dcSFilip Drazic reg &= ~lowest_set; 220b516b7dcSFilip Drazic 2211ac6af11SRonak Jain if (node > NODE_UNKNOWN && node < NODE_MAX) { 2221ac6af11SRonak Jain if (pm_wakeup_nodes_set[node] == 0U) { 2231ac6af11SRonak Jain ret = pm_set_wakeup_source(NODE_APU, node, 1U); 2241ac6af11SRonak Jain pm_wakeup_nodes_set[node] = (ret == PM_RET_SUCCESS) ? 1U : 0U; 2251ac6af11SRonak Jain } 226b516b7dcSFilip Drazic } 227b516b7dcSFilip Drazic } 228b516b7dcSFilip Drazic } 229b516b7dcSFilip Drazic } 230b516b7dcSFilip Drazic 231c8284409SSoren Brinkmann /** 232c8284409SSoren Brinkmann * pm_get_proc() - returns pointer to the proc structure 233c8284409SSoren Brinkmann * @cpuid: id of the cpu whose proc struct pointer should be returned 234c8284409SSoren Brinkmann * 235c8284409SSoren Brinkmann * Return: pointer to a proc structure if proc is found, otherwise NULL 236c8284409SSoren Brinkmann */ 237ffa91031SVenkatesh Yadav Abbarapu const struct pm_proc *pm_get_proc(uint32_t cpuid) 238c8284409SSoren Brinkmann { 239eb0d2b17SVenkatesh Yadav Abbarapu if (cpuid < ARRAY_SIZE(pm_procs_all)) { 240c8284409SSoren Brinkmann return &pm_procs_all[cpuid]; 241eb0d2b17SVenkatesh Yadav Abbarapu } 242c8284409SSoren Brinkmann 243c8284409SSoren Brinkmann return NULL; 244c8284409SSoren Brinkmann } 245c8284409SSoren Brinkmann 246c8284409SSoren Brinkmann /** 247c8284409SSoren Brinkmann * pm_get_proc_by_node() - returns pointer to the proc structure 248c8284409SSoren Brinkmann * @nid: node id of the processor 249c8284409SSoren Brinkmann * 250c8284409SSoren Brinkmann * Return: pointer to a proc structure if proc is found, otherwise NULL 251c8284409SSoren Brinkmann */ 252c8284409SSoren Brinkmann const struct pm_proc *pm_get_proc_by_node(enum pm_node_id nid) 253c8284409SSoren Brinkmann { 254c8284409SSoren Brinkmann for (size_t i = 0; i < ARRAY_SIZE(pm_procs_all); i++) { 255eb0d2b17SVenkatesh Yadav Abbarapu if (nid == pm_procs_all[i].node_id) { 256c8284409SSoren Brinkmann return &pm_procs_all[i]; 257c8284409SSoren Brinkmann } 258eb0d2b17SVenkatesh Yadav Abbarapu } 259c8284409SSoren Brinkmann return NULL; 260c8284409SSoren Brinkmann } 261c8284409SSoren Brinkmann 262c8284409SSoren Brinkmann /** 263c8284409SSoren Brinkmann * pm_get_cpuid() - get the local cpu ID for a global node ID 264c8284409SSoren Brinkmann * @nid: node id of the processor 265c8284409SSoren Brinkmann * 266c8284409SSoren Brinkmann * Return: the cpu ID (starting from 0) for the subsystem 267c8284409SSoren Brinkmann */ 268ffa91031SVenkatesh Yadav Abbarapu static uint32_t pm_get_cpuid(enum pm_node_id nid) 269c8284409SSoren Brinkmann { 270c8284409SSoren Brinkmann for (size_t i = 0; i < ARRAY_SIZE(pm_procs_all); i++) { 271eb0d2b17SVenkatesh Yadav Abbarapu if (pm_procs_all[i].node_id == nid) { 272c8284409SSoren Brinkmann return i; 273c8284409SSoren Brinkmann } 274eb0d2b17SVenkatesh Yadav Abbarapu } 275c8284409SSoren Brinkmann return UNDEFINED_CPUID; 276c8284409SSoren Brinkmann } 277c8284409SSoren Brinkmann 278c8284409SSoren Brinkmann const struct pm_proc *primary_proc = &pm_procs_all[0]; 279c8284409SSoren Brinkmann 280c8284409SSoren Brinkmann /** 281c8284409SSoren Brinkmann * pm_client_suspend() - Client-specific suspend actions 282c8284409SSoren Brinkmann * 283c8284409SSoren Brinkmann * This function should contain any PU-specific actions 284c8284409SSoren Brinkmann * required prior to sending suspend request to PMU 285b516b7dcSFilip Drazic * Actions taken depend on the state system is suspending to. 286c8284409SSoren Brinkmann */ 287ffa91031SVenkatesh Yadav Abbarapu void pm_client_suspend(const struct pm_proc *proc, uint32_t state) 288c8284409SSoren Brinkmann { 28903b80773SStefan Krsmanovic bakery_lock_get(&pm_client_secure_lock); 29003b80773SStefan Krsmanovic 291eb0d2b17SVenkatesh Yadav Abbarapu if (state == PM_STATE_SUSPEND_TO_RAM) { 292b516b7dcSFilip Drazic pm_client_set_wakeup_sources(); 293eb0d2b17SVenkatesh Yadav Abbarapu } 294b516b7dcSFilip Drazic 295c8284409SSoren Brinkmann /* Set powerdown request */ 296c8284409SSoren Brinkmann mmio_write_32(APU_PWRCTL, mmio_read_32(APU_PWRCTL) | proc->pwrdn_mask); 29703b80773SStefan Krsmanovic 29803b80773SStefan Krsmanovic bakery_lock_release(&pm_client_secure_lock); 299c8284409SSoren Brinkmann } 300c8284409SSoren Brinkmann 301c8284409SSoren Brinkmann 302c8284409SSoren Brinkmann /** 303c8284409SSoren Brinkmann * pm_client_abort_suspend() - Client-specific abort-suspend actions 304c8284409SSoren Brinkmann * 305c8284409SSoren Brinkmann * This function should contain any PU-specific actions 306c8284409SSoren Brinkmann * required for aborting a prior suspend request 307c8284409SSoren Brinkmann */ 308c8284409SSoren Brinkmann void pm_client_abort_suspend(void) 309c8284409SSoren Brinkmann { 310c8284409SSoren Brinkmann /* Enable interrupts at processor level (for current cpu) */ 311c8284409SSoren Brinkmann gicv2_cpuif_enable(); 31203b80773SStefan Krsmanovic 31303b80773SStefan Krsmanovic bakery_lock_get(&pm_client_secure_lock); 31403b80773SStefan Krsmanovic 315c8284409SSoren Brinkmann /* Clear powerdown request */ 316c8284409SSoren Brinkmann mmio_write_32(APU_PWRCTL, 317c8284409SSoren Brinkmann mmio_read_32(APU_PWRCTL) & ~primary_proc->pwrdn_mask); 31803b80773SStefan Krsmanovic 31903b80773SStefan Krsmanovic bakery_lock_release(&pm_client_secure_lock); 320c8284409SSoren Brinkmann } 321c8284409SSoren Brinkmann 322c8284409SSoren Brinkmann /** 323c8284409SSoren Brinkmann * pm_client_wakeup() - Client-specific wakeup actions 324c8284409SSoren Brinkmann * 325c8284409SSoren Brinkmann * This function should contain any PU-specific actions 326c8284409SSoren Brinkmann * required for waking up another APU core 327c8284409SSoren Brinkmann */ 328c8284409SSoren Brinkmann void pm_client_wakeup(const struct pm_proc *proc) 329c8284409SSoren Brinkmann { 330ffa91031SVenkatesh Yadav Abbarapu uint32_t cpuid = pm_get_cpuid(proc->node_id); 331c8284409SSoren Brinkmann 332eb0d2b17SVenkatesh Yadav Abbarapu if (cpuid == UNDEFINED_CPUID) { 333c8284409SSoren Brinkmann return; 334eb0d2b17SVenkatesh Yadav Abbarapu } 335c8284409SSoren Brinkmann 33603b80773SStefan Krsmanovic bakery_lock_get(&pm_client_secure_lock); 33703b80773SStefan Krsmanovic 338c8284409SSoren Brinkmann /* clear powerdown bit for affected cpu */ 339c8284409SSoren Brinkmann uint32_t val = mmio_read_32(APU_PWRCTL); 340c8284409SSoren Brinkmann val &= ~(proc->pwrdn_mask); 341c8284409SSoren Brinkmann mmio_write_32(APU_PWRCTL, val); 34203b80773SStefan Krsmanovic 34303b80773SStefan Krsmanovic bakery_lock_release(&pm_client_secure_lock); 344c8284409SSoren Brinkmann } 34534c57139SSiva Durga Prasad Paladugu 34634c57139SSiva Durga Prasad Paladugu enum pm_ret_status pm_set_suspend_mode(uint32_t mode) 34734c57139SSiva Durga Prasad Paladugu { 34834c57139SSiva Durga Prasad Paladugu if ((mode != PM_SUSPEND_MODE_STD) && 349eb0d2b17SVenkatesh Yadav Abbarapu (mode != PM_SUSPEND_MODE_POWER_OFF)) { 35034c57139SSiva Durga Prasad Paladugu return PM_RET_ERROR_ARGS; 351eb0d2b17SVenkatesh Yadav Abbarapu } 35234c57139SSiva Durga Prasad Paladugu 35334c57139SSiva Durga Prasad Paladugu suspend_mode = mode; 35434c57139SSiva Durga Prasad Paladugu return PM_RET_SUCCESS; 35534c57139SSiva Durga Prasad Paladugu } 356